0023950: Names and visibility of points not saved when writing XCAF Document into...

[occt.git] / dox / user_guides / draw_test_harness.md

Draw Test Harness  {#occt_user_guides__test_harness}
===============================

@tableofcontents
 
@section occt_draw_1 Introduction

This manual explains how to use Draw, the test harness for Open CASCADE Technology (**OCCT**). It provides basic documentation on using Draw. For advanced information on Draw and its applications, see our offerings on our web site at <a href="http://www.opencascade.org/support/training">http://www.opencascade.org/support/training</a>  

Draw is a command interpreter based on TCL and a graphical system used to test and demonstrate Open CASCADE Technology modeling libraries. 


@subsection occt_draw_1_1 Overview

Draw is a test harness for Open CASCADE Technology. It provides a flexible and easy to use means of testing and demonstrating the OCCT modeling libraries. 

Draw can be used interactively to create, display and modify objects such as curves, surfaces and topological shapes. 

Scripts may be written to customize Draw and perform tests. New types of objects and new commands may be added using the C++ programing language. 

Draw consists of: 

  * A command interpreter based on the TCL command language.
  * A 3d graphic viewer based on the X system.
  * A basic set of commands covering scripts, variables and graphics.
  * A set of geometric commands allowing the user to create and modify curves and surfaces and to use OCCT geometry algorithms. This set of commands is optional.
  * A set of topological commands allowing the user to create and modify BRep shapes and to use the OCCT topology algorithms.


There is also a set of commands for each delivery unit in the modeling libraries: 

  * GEOMETRY, 
  * TOPOLOGY, 
  * ADVALGOS, 
  * GRAPHIC, 
  * PRESENTATION. 


@subsection occt_draw_1_2 Contents of this documentation

This documentation describes: 

  * The command language.
  * The basic set of commands.
  * The graphical commands.
  * The Geometry set of commands.
  * The Topology set of commands.

This document does not describe other sets of commands and does not explain how to extend Draw using C++. 

This document is a reference manual. It contains a full description of each command. All descriptions have the format illustrated below for the exit command. 

~~~~~
exit
~~~~~

Terminates the Draw, TCL session. If the commands are read from a file using the source command, this will terminate the file. 

**Example:** 

~~~~~
# this is a very short example 
exit 
~~~~~


@subsection occt_draw_1_3 Getting started

Install Draw and launch Emacs. Get a command line in Emacs using *Esc x* and key in *woksh*. 

All DRAW Test Harness can be activated in the common executable called **DRAWEXE**. They are grouped in toolkits and can be loaded at run-time thereby implementing dynamically loaded plug-ins. Thus, it is possible to work only with the required commands adding them dynamically without leaving the Test Harness session. 

Declaration of available plug-ins is done through the special resource file(s). The *pload* command loads the plug-in in accordance with the specified resource file and activates the commands implemented in the plug-in. 

@subsubsection occt_draw_1_3_1 Launching DRAW Test Harness

Test Harness executable *DRAWEXE* is located in the <i>$CASROOT/\<platform\>/bin</i> directory (where \<platform\> is Win for Windows and Linux for Linux operating systems). Prior to launching it is important to make sure that the environment is correctly set-up (usually this is done automatically after the installation process on Windows or after launching specific scripts on Linux).  


@subsubsection occt_draw_1_3_2 Plug-in resource file

Open CASCADE Technology is shipped with the DrawPlugin resource file located in the <i>$CASROOT/src/DrawResources</i> directory. 

The format of the file is compliant with standard Open CASCADE Technology resource files (see the *Resource_Manager.cdl* file for details). 

Each key defines a sequence of either further (nested) keys or a name of the dynamic library. Keys can be nested down to an arbitrary level. However, cyclic dependencies between the keys are not checked. 

**Example:** (excerpt from DrawPlugin): 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
OCAF               : VISUALIZATION, OCAFKERNEL 
VISUALIZATION      : AISV 
OCAFKERNEL         : DCAF 

DCAF               : TKDCAF 
AISV               : TKViewerTest 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_1_3_3 Activation of commands implemented in the plug-in

To load a plug-in declared in the resource file and to activate the commands the following command must be used in Test Harness: 

~~~~~
pload [-PluginFileName] [[Key1] [Key2]...]
~~~~~

where: 

* <i>-PluginFileName</i> - defines the name of a plug-in resource file (prefix "-" is mandatory) described above. If this parameter is omitted then the default name *DrawPlugin* is used. 
* *Key…* - defines the key(s) enumerating plug-ins to be loaded. If no keys are specified then the key named *DEFAULT* is used (if there is no such key in the file then no plug-ins are loaded). 

According to the OCCT resource file management rules, to access the resource file the environment variable *CSF_PluginFileNameDefaults* (and optionally *CSF_PluginFileNameUserDefaults*) must be set and point to the directory storing the resource file. If it is omitted then the plug-in resource file will be searched in the <i>$CASROOT/src/DrawResources</i> directory. 

~~~~~
Draw[]        pload -DrawPlugin OCAF 
~~~~~
This command will search the resource file *DrawPlugin* using variable *CSF_DrawPluginDefaults* (and *CSF_DrawPluginUserDefaults*) and will start with the OCAF key. Since the *DrawPlugin* is the file shipped with Open CASCADE Technology it will be found in the <i>$CASROOT/src/DrawResources</i> directory (unless this location is redefined by user's variables). The OCAF key will be recursively extracted into two toolkits/plug-ins: *TKDCAF* and *TKViewerTest* (e.g. on Windows they correspond to *TKDCAF.dll* and *TKViewerTest.dll*). Thus, commands implemented for Visualization and OCAF will be loaded and activated in Test Harness. 

~~~~~
Draw[]        pload (equivalent to pload -DrawPlugin DEFAULT). 
~~~~~
This command will find the default DrawPlugin file and the DEFAULT key. The latter finally maps to the TKTopTest toolkit which implements basic modeling commands. 


@section occt_draw_2 The Command Language

@subsection occt_draw_2_1 Overview

The command language used in Draw is Tcl. Tcl documentation such as "TCL and the TK Toolkit" by John K. Ousterhout (Addison-Wesley) will prove useful if you intend to use Draw extensively. 

This chapter is designed to give you a short outline of both the TCL language and some extensions included in Draw. The following topics are covered: 

  * Syntax of the TCL language.
  * Accessing variables in TCL and Draw.
  * Control structures.
  * Procedures.

@subsection occt_draw_2_2 Syntax of TCL

TCL is an interpreted command language, not a structured language like C, Pascal, LISP or Basic. It uses a shell similar to that of csh. TCL is, however, easier to use than csh because control structures and procedures are easier to define. As well, because TCL does not assign a process to each command, it is faster than csh. 

The basic program for TCL is a script. A script consists of one or more commands. Commands are separated by new lines or semicolons. 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
set a 24 
set b 15 
set a 25; set b 15 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Each command consists of one or more *words*; the first word is the name of a command and additional words are arguments to that command. 

Words are separated by spaces or tabs. In the preceding example each of the four commands has three words. A command may contain any number of words and each word is a string of arbitrary length. 

The evaluation of a command by TCL is done in two steps. In the first step, the command is parsed and broken into words. Some substitutions are also performed. In the second step, the command procedure corresponding to the first word is called and the other words are interpreted as arguments. In the first step, there is only string manipulation, The words only acquire *meaning* in the second step by the command procedure. 

The following substitutions are performed by TCL: 

Variable substitution is triggered by the $ character (as with csh), the content of the variable is substitued; { } may be used as in csh to enclose the name of the variable. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# set a variable value 
set file documentation 
puts $file #to display file contents on the screen 

# a simple substitution, set psfile to documentation.ps 
set psfile $file.ps 
puts $psfile 

# another substitution, set pfile to documentationPS 
set pfile ${file}PS 

# a last one, 
# delete files NEWdocumentation and OLDdocumentation 
foreach prefix {NEW OLD} {rm $prefix$file} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Command substitution is triggered by the [ ] characters. The brackets must enclose a valid script. The script is evaluated and the result is substituted. 

Compare command construction in csh. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
set degree 30 
set pi 3.14159265 
# expr is a command evaluating a numeric expression 
set radian [expr $pi*$degree/180] 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Backslash substitution is triggered by the backslash character. It is used to insert special characters like $, [ , ] , etc. It is also useful to insert a new line, a backslash terminated line is continued on the following line. 

TCL uses two forms of *quoting* to prevent substitution and word breaking. 

Double quote *quoting* enables the definition of a string with space and tabs as a single word. Substitutions are still performed inside the inverted commas " ". 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# set msg to ;the price is 12.00; 
set price 12.00 
set msg ;the price is $price; 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Braces *quoting* prevents all substitutions. Braces are also nested. The main use of braces is to defer evaluation when defining procedures and control structures. Braces are used for a clearer presentation of TCL scripts on several lines. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
set x 0 
# this will loop for ever 
# because while argument is ;0  3; 
while ;$x  3; {set x [expr $x+1]} 
# this will terminate as expected because 
# while argument is {$x  3} 
while {$x  3} {set x [expr $x+1]} 
# this can be written also 
while {$x  3} { 
set x [expr $x+1] 
} 
# the following cannot be written 
# because while requires two arguments 
while {$x  3} 
{ 
set x [expr $x+1] 
} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Comments start with a \# character as the first non-blank character in a command. To add a comment at the end of the line, the comment must be preceded by a semi-colon to end the preceding command. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# This is a comment 
set a 1 # this is not a comment 
set b 1; # this is a comment 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The number of words is never changed by substitution when parsing in TCL. For example, the result of a substitution is always a single word. This is different from csh but convenient as the behavior of the parser is more predictable. It may sometimes be necessary to force a second round of parsing. **eval** accomplishes this: it accepts several arguments, concatenates them and executes the resulting script. 


**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# I want to delete two files 

set files ;foo bar; 

# this will fail because rm will receive only one argument 
# and complain that ;foo bar; does not exit 

exec rm $files 

# a second evaluation will do it 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsection occt_draw_2_3 Accessing variables in TCL and Draw

TCL variables have only string values. Note that even numeric values are stored as string literals, and computations using the **expr** command start by parsing the strings. Draw, however, requires variables with other kinds of values such as curves, surfaces or topological shapes. 

TCL provides a mechanism to link user data to variables. Using this functionality, Draw defines its variables as TCL variables with associated data. 

The string value of a Draw variable is meaningless. It is usually set to the name of the variable itself. Consequently, preceding a Draw variable with a <i>$</i> does not change the result of a command. The content of a Draw variable is accessed using appropriate commands. 

There are many kinds of Draw variables, and new ones may be added with C++. Geometric and topological variables are described below. 

Draw numeric variables can be used within an expression anywhere a Draw command requires a numeric value. The *expr* command is useless in this case as the variables are stored not as strings but as floating point values. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# dset is used for numeric variables 
# pi is a predefined Draw variable 
dset angle pi/3 radius 10 
point p radius*cos(angle) radius*sin(angle) 0 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
It is recommended that you use TCL variables only for strings and Draw for numerals. That way, you will avoid the *expr* command. As a rule, Geometry and Topology require numbers but no strings. 

@subsubsection occt_draw_2_3_1 set, unset

Syntax:                  

~~~~~
set varname [value] 
unset varname [varname varname ...] 
~~~~~

*set* assigns a string value to a variable. If the variable does not already exist, it is created. 

Without a value, *set* returns the content of the variable. 

*unset* deletes variables. It is is also used to delete Draw variables. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
set a "Hello world"
set b "Goodbye" 
set a 
== "Hello world" 
unset a b 
set a 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

**Note**, that the *set* command can set only one variable, unlike the *dset* command. 


@subsubsection occt_draw_2_3_2 dset, dval

Syntax

~~~~~
dset var1 value1 vr2 value2 ... 
dval name 
~~~~~

*dset* assigns values to Draw numeric variables. The argument can be any numeric expression including Draw numeric variables. Since all Draw commands expect a numeric expression, there is no need to use $ or *expr*. The *dset* command can assign several variables. If there is an odd number of arguments, the last variable will be assigned a value of 0. If the variable does not exist, it will be created. 

*dval* evaluates an expression containing Draw numeric variables and returns the result as a string, even in the case of a single variable. This is not used in Draw commands as these usually interpret the expression. It is used for basic TCL commands expecting strings. 


**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# z is set to 0 
dset x 10 y 15 z 
== 0 

# no $ required for Draw commands 
point p x y z 

# "puts" prints a string 
puts ;x = [dval x], cos(x/pi) = [dval cos(x/pi)]; 
== x = 10, cos(x/pi) = -0.99913874099467914 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

**Note,** that in TCL, parentheses are not considered to be special characters. Do not forget to quote an expression if it contains spaces in order to avoid parsing different words. <i>(a + b)</i> is parsed as three words: <i>"(a + b)"</i> or <i>(a+b)</i> are correct.


@subsection occt_draw_2_4 lists

TCL uses lists. A list is a string containing elements separated by spaces or tabs. If the string contains braces, the braced part accounts as one element. 

This allows you to insert lists within lists. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# a list of 3 strings 
;a b c; 

# a list of two strings the first is a list of 2 
;{a b} c; 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Many TCL commands return lists and **foreach** is a useful way to create loops on list elements. 

@subsubsection occt_draw_2_5 Control Structures

TCL allows looping using control structures. The control structures are implemented by commands and their syntax is very similar to that of their C counterparts (**if**, **while**, **switch**, etc.). In this case, there are two main differences between TCL and C: 

* You use braces instead of parentheses to enclose conditions. 
* You do not start the script on the next line of your command. 


@subsubsection occt_draw_2_5_1 if

Syntax       

~~~~~
if condition script [elseif script .... else script] 
~~~~~

**If** evaluates the condition and the script to see whether the condition is true. 



**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
if {$x  0} { 
puts ;positive; 
} elseif {$x == 0} { 
puts ;null; 
} else { 
puts ;negative; 
} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_2_5_2 while, for, foreach

Syntax:                  


~~~~~~
while condition script 
for init condition reinit script 
foreach varname list script 
~~~~~

The three loop structures are similar to their C or csh equivalent. It is important to use braces to delay evaluation. **foreach** will assign the elements of the list to the variable before evaluating the script. \

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# while example 
dset x 1.1 
while {[dval x]  100} { 
  circle c 0 0 x 
  dset x x*x 
} 
# for example 
# incr var d, increments a variable of d (default 1) 
for {set i 0} {$i  10} {incr i} { 
  dset angle $i*pi/10 
  point p$i cos(angle0 sin(angle) 0 
} 
# foreach example 
foreach object {crapo tomson lucas} {display $object} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_2_5_3 break, continue

Syntax:                  

~~~~~
break 
continue 
~~~~~

Within loops, the **break** and **continue** commands have the same effect as in C. 

**break** interrupts the innermost loop and **continue** jumps to the next iteration. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# search the index for which t$i has value ;secret; 
for {set i 1} {$i = 100} {incr i} { 
  if {[set t$i] == ;secret;} break; 
} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsection occt_draw_2_6 Procedures

TCL can be extended by defining procedures using the **proc** command, which sets up a context of local variables, binds arguments and executes a TCL script. 

The only problematic aspect of procedures is that variables are strictly local, and as they are implicitly created when used, it may be difficult to detect errors. 

There are two means of accessing a variable outside the scope of the current procedures: **global** declares a global variable (a variable outside all procedures); **upvar** accesses a variable in the scope of the caller. Since arguments in TCL are always string values, the only way to pass Draw variables is by reference, i.e. passing the name of the variable and using the **upvar** command as in the following examples. 

As TCL is not a strongly typed language it is very difficult to detect programming errors and debugging can be tedious. TCL procedures are, of course, not designed for large scale software development but for testing and simple command or interactive writing. 


@subsubsection occt_draw_2_6_1 proc

Syntax:

~~~~~
proc argumentlist script 
~~~~~

**proc** defines a procedure. An argument may have a default value. It is then a list of the form {argument value}. The script is the body of the procedure. 

**return** gives a return value to the procedure. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# simple procedure 
proc hello {} { 
  puts ;hello world; 
} 
# procedure with arguments and default values 
proc distance {x1 y1 {x2 0} {y2 0}} { 
  set d [expr (x2-x1)*(x2-x1) + (y2-y1)*(y2-y1)] 
  return [expr sqrt(d)] 
} 
proc fact n { 
  if {$n == 0} {return 1} else { 
    return [expr n*[fact [expr n -1]]] 
  } 
} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


@subsubsection occt_draw_2_6_2 global, upvar

Syntax:                 

~~~~~
global varname [varname ...] 
upvar varname localname [varname localname ...] 
~~~~~


**global** accesses high level variables. Unlike C, global variables are not visible in procedures. 

**upvar** gives a local name to a variable in the caller scope. This is useful when an argument is the name of a variable instead of a value. This is a call by reference and is the only way to use Draw variables as arguments. 

**Note** that in the following examples the \$ character is always necessarily used to access the arguments.
 
**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# convert degree to radian 
# pi is a global variable 
proc deg2rad (degree} { 
  return [dval pi*$degree/2.] 
} 
# create line with a point and an angle 
proc linang {linename x y angle} { 
  upvar linename l 
  line l $x $y cos($angle) sin($angle) 
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@section occt_draw_3 Basic Commands

This chapter describes all the commands defined in the basic Draw package. Some are TCL commands, but most of them have been formulated in Draw. These commands are found in all Draw applications. The commands are grouped into four sections: 

  * General commands, which are used for Draw and TCL management.
  * Variable commands, which are used to manage Draw variables such as storing and dumping.
  * Graphic commands, which are used to manage the graphic system, and so pertain to views.
  * Variable display commands, which are used to manage the display of objects within given views.

Note that Draw also features a GUI task bar providing an alternative way to give certain general, graphic and display commands 


@subsection occt_draw_3_1 General commands

This section describes several useful commands:

  * **help** to get information, 
  * **source** to eval a script from a file, 
  * **spy** to capture the commands in a file,
  * **cpulimit** to limit the process cpu time, 
  * **wait** to waste some time, 
  * **chrono** to time commands. 

@subsubsection occt_draw_3_1_1 help

Syntax:                  

~~~~~
help [command [helpstring group]] 
~~~~~

Provides help or modifies the help information. 

**help** without arguments lists all groups and the commands in each group. 

Specifying the command returns its syntax and in some cases, information on the command, The joker \* is automatically added at the end so that all completing commands are returned as well. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# Gives help on all commands starting with *a* 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


@subsubsection occt_draw_3_1_2 source

Syntax:

~~~~~
source filename 
~~~~~
Executes a file. 

The **exit** command will terminate the file. 

@subsubsection occt_draw_3_1_3 spy

Syntax:                  

~~~~~
spy [filename] 
~~~~~

Saves interactive commands in the file. If spying has already been performed, the current file is closed. **spy** without an argument closes the current file and stops spying. If a file already exists, the file is overwritten. Commands are not appended. 

If a command returns an error it is saved with a comment mark. 

The file created by **spy** can be executed with the **source** command. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# all commands will be saved in the file ;session; 
spy session 
# the file ;session; is closed and commands are not saved 
spy 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



@subsubsection occt_draw_3_1_4 cpulimit

Syntax:                  

~~~~~
cpulimit [nbseconds] 
~~~~~

**cpulimit**limits a process after the number of seconds specified in nbseconds. It is used in tests to avoid infinite loops. **cpulimit** without arguments removes all existing limits. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
#limit cpu to one hour 
cpulimit 3600 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_3_1_5 wait

Syntax:
~~~~~
wait [nbseconds] 
~~~~~
Suspends execution for the number of seconds specified in *nbseconds*. The default value is ten (10) seconds. This is a useful command for a slide show. 

~~~~~
# You have ten seconds ... 
wait 
~~~~~

@subsubsection occt_draw_3_1_6 chrono

Syntax:                  

~~~~~
chrono [ name start/stop/reset/show] 
~~~~~

Without arguments, **chrono** activates Draw chronometers. The elapsed time ,cpu system and cpu user times for each command will be printed. 

With arguments, **chrono** is used to manage activated chronometers. You can perform the following actions with a chronometer. 
  * run the chronometer (start).
  * stop the chronometer (stop).
  * reset the chronometer to 0 (reset).
  * display the current time (show).

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
chrono 
==Chronometers activated. 
ptorus t 20 5 
==Elapsed time: 0 Hours 0 Minutes 0.0318 Seconds 
==CPU user time: 0.01 seconds 
==CPU system time: 0 seconds 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsection occt_draw_3_2  Variable management commands

@subsubsection occt_draw_3_2_1 isdraw, directory

Syntax:                  
~~~~~
isdraw varname 
directory [pattern] 
~~~~~

**isdraw** tests to see if a variable is a Draw variable. **isdraw** will return 1 if there is a Draw value attached to the variable. 

Use **directory** to return a list of all Draw global variables matching a pattern. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
set a 1 
isdraw a 
=== 0 

dset a 1 
isdraw a 
=== 1 

circle c 0 0 1 0 5 
isdraw c 
=== 1 

# to destroy all Draw objects with name containing curve 
foreach var [directory *curve*] {unset $var} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


@subsubsection occt_draw_3_2_2 whatis, dump

Syntax:

~~~~~
whatis varname [varname ...] 
dump varname [varname ...] 
~~~~~

**whatis** returns short information about a Draw variable. This is usually the type name. 

**dump** returns a brief type description, the coordinates, and if need be, the parameters of a Draw variable. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
circle c 0 0 1 0 5 
whatis c 
c is a 2d curve 

dump c 

***** Dump of c ***** 
Circle 
Center :0, 0 
XAxis :1, 0 
YAxis :-0, 1 
Radius :5 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

**Note** The behavior of *whatis* on other variables (not Draw) is not excellent. 


@subsubsection occt_draw_3_2_3 rename, copy

Syntax:      
~~~~~
rename varname tovarname [varname tovarname ...] 
copy varname tovarname [varname tovarname ...] 
~~~~~

  * **rename** changes the name of a Draw variable. The original variable will no longer exist. Note that the content is not modified. Only the name is changed. 
  * **copy** creates a new variable with a copy of the content of an existing variable. The exact behavior of **copy** is type dependent; in the case of certain topological variables, the content may still be shared. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
circle c1 0 0 1 0 5 
rename c1 c2 

# curves are copied, c2 will not be modified 
copy c2 c3 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_3_2_4 datadir, save, restore

Syntax:
~~~~~
datadir [directory] 
save variable [filename] 
restore filename [variablename] 
~~~~~

  * **datadir** without arguments prints the path of the current data directory. 
  * **datadir** with an argument sets the data directory path. \

If the path starts with a dot (.) only the last directory name will be changed in the path. 

  * **save** writes a file in the data directory with the content of a variable. By default the name of the file is the name of the variable. To give a different name use a second argument. 
  * **restore** reads the content of a file in the data directory in a local variable. By default, the name of the variable is the name of the file. To give a different name, use a second argument. 

The exact content of the file is type-dependent. They are usually ASCII files and so, architecture independent. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# note how TCL accesses shell environment variables 
# using $env() 
datadir 
==. 

datadir $env(WBCONTAINER)/data/default 
==/adv_20/BAG/data/default 

box b 10 20 30 
save b theBox 
==/adv_20/BAG/data/default/theBox 

# when TCL does not find a command it tries a shell command 
ls [datadir] 
== theBox 

restore theBox 
== theBox 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsection occt_draw_3_3 User defined commands

*DrawTrSurf* provides commands to create and display a Draw **geometric** variable from a *Geom_Geometry* object and also get a *Geom_Geometry* object from a Draw geometric variable name. 

*DBRep* provides commands to create and display a Draw **topological** variable from a *TopoDS_Shape* object and also get a *TopoDS_Shape* object from a Draw topological variable name. 

@subsubsection occt_draw_3_3_1 set

#### In *DrawTrSurf* package:

~~~~~
void Set(Standard_CString& Name,const gp_Pnt& G) ; 
void Set(Standard_CString& Name,const gp_Pnt2d& G) ; 
void Set(Standard_CString& Name, 
const Handle(Geom_Geometry)& G) ; 
void Set(Standard_CString& Name, 
const Handle(Geom2d_Curve)& C) ; 
void Set(Standard_CString& Name, 
const Handle(Poly_Triangulation)& T) ; 
void Set(Standard_CString& Name, 
const Handle(Poly_Polygon3D)& P) ; 
void Set(Standard_CString& Name, 
const Handle(Poly_Polygon2D)& P) ; 
~~~~~

#### In *DBRep* package:

~~~~~
void Set(const Standard_CString Name, 
const TopoDS_Shape& S) ; 
~~~~~

Example of *DrawTrSurf*

~~~~~
Handle(Geom2d_Circle) C1 = new Geom2d_Circle 
(gce_MakeCirc2d (gp_Pnt2d(50,0,) 25)); 
DrawTrSurf::Set(char*, C1); 
~~~~~

Example of *DBRep* 

~~~~~
TopoDS_Solid B; 
B = BRepPrimAPI_MakeBox (10,10,10); 
DBRep::Set(char*,B); 
~~~~~

@subsubsection occt_draw_3_3_2 get

#### In *DrawTrSurf* package:
 
~~~~~
Handle_Geom_Geometry Get(Standard_CString& Name) ; 
~~~~~

#### In *DBRep* package:

~~~~~
TopoDS_Shape Get(Standard_CString& Name, 
const TopAbs_ShapeEnum Typ = TopAbs_SHAPE, 
const Standard_Boolean Complain 
= Standard_True) ; 
~~~~~

Example of *DrawTrSurf*

~~~~~
Standard_Integer MyCommand 
(Draw_Interpretor& theCommands, 
Standard_Integer argc, char** argv) 
{...... 
// Creation of a Geom_Geometry from a Draw geometric 
// name 
Handle (Geom_Geometry) aGeom= DrawTrSurf::Get(argv[1]); 
} 
~~~~~

Example of *DBRep*

~~~~~
Standard_Integer MyCommand 
(Draw_Interpretor& theCommands, 
Standard_Integer argc, char** argv) 
{...... 
// Creation of a TopoDS_Shape from a Draw topological 
// name 
TopoDS_Solid B = DBRep::Get(argv[1]); 
} 
~~~~~

@section occt_draw_4 Graphic Commands

Graphic commands are used to manage the Draw graphic system. Draw provides a 2d and a 3d viewer with up to 30 views. Views are numbered and the index of the view is displayed in the window’s title. Objects are displayed in all 2d views or in all 3d views, depending on their type. 2d objects can only be viewed in 2d views while 3d objects – only in 3d views correspondingly. 

@subsection occt_draw_4_1 Axonometric viewer

@subsubsection occt_draw_4_1_1 view, delete

Syntax:                  
~~~~~
view index type [X Y W H] 
delete [index] 
~~~~~

**view** is the basic view creation command: it creates a new view with the given index. If a view with this index already exits, it is deleted. The view is created with default parameters and X Y W H are the position and dimensions of the window on the screen. Default values are 0, 0, 500, 500. 

As a rule it is far simpler either to use the procedures **axo**, **top**, **left** or to click on the desired view type in the menu under *Views* in the task bar.. 

**delete** deletes a view. If no index is given, all the views are deleted. 

Type selects from the following range: 

  * *AXON* : Axonometric view
  * *PERS* : Perspective view
  * <i>+X+Y</i> : View on both axes (i.e. a top view), other codes are <i>-X+Y</i>, <i>+Y-Z</i>, etc.
  * <i>-2D-</i> : 2d view

The index, the type, the current zoom are displayed in the window title . 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# this is the content of the mu4 procedure 
proc mu4 {} { 
delete 
view 1 +X+Z 320 20 400 400 
view 2 +X+Y 320 450 400 400 
view 3 +Y+Z 728 20 400 400 
view 4 AXON 728 450 400 400 
} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

See also: **axo, pers, top, bottom, left, right, front, back, mu4, v2d, av2d, smallview** 

@subsubsection occt_draw_4_1_2  axo, pers, top, ...

Syntax:      

~~~~~
axo 
pers 
... 
smallview type 
~~~~~

All these commands are procedures used to define standard screen layout. They delete all existing views and create new ones. The layout usually complies with the European convention, i.e. a top view is under a front view. 

  * **axo** creates a large window axonometric view;
  * **pers** creates a large window perspective view;
  * **top**, **bottom**, **left**, **right**, **front**, **back** create a large window axis view;
  * **mu4** creates four small window views: front, left, top and axo.
  * **v2d** creates a large window 2d view.
  * **av2d** creates two small window views, one 2d and one axo
  * **smallview** creates a view at the bottom right of the screen of the given type. 

See also: **view**, **delete** 

@subsubsection occt_draw_4_1_3 mu, md, 2dmu, 2dmd, zoom, 2dzoom

Syntax:

~~~~~
    mu [index] value 
    2dmu [index] value 
    zoom [index] value 
    wzoom 
~~~~~

* **mu** (magnify up) increases the zoom in one or several views by a factor of 10%. 
* **md** (magnify down) decreases the zoom by the inverse factor. **2dmu** and **2dmd** 
perform the same on one or all 2d views. 
* **zoom** and **2dzoom** set the zoom factor to a value specified by you. The current zoom factor is always displayed in the window’s title bar. Zoom 20 represents a full screen view in a large window; zoom 10, a full screen view in a small one. 
* **wzoom** (window zoom) allows you to select the area you want to zoom in on with the mouse. You will be prompted to give two of the corners of the area that you want to magnify and the rectangle so defined will occupy the window of the view. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
    # set a zoom of 2.5 
    zoom 2.5 

    # magnify by 10% 
    mu 1 

    # magnify by 20% 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
See also: **fit**, **2dfit** 


@subsubsection occt_draw_4_14 pu, pd, pl, pr, 2dpu, 2dpd, 2dpl, 2dpr

Syntax:                  

~~~~~
pu [index] 
pd [index] 
~~~~~

The <i>p_</i> commands are used to pan. **pu** and **pd** pan up and down respectively; **pl** and **pr** pan to the left and to the right respectively. Each time the view is displaced by 40 pixels. When no index is given, all views will pan in the direction specified. 
~~~~~
# you have selected one anonometric view
pu
# or
pu 1

# you have selected an mu4 view; the object in the third view will pan up
pu 3
~~~~~
See also: **fit**, **2dfit** 


@subsubsection occt_draw_4_1_5 fit, 2dfit

Syntax:      

~~~~~
fit [index] 
2dfit [index] 
~~~~~

**fit** computes the best zoom and pans on the content of the view. The content of the view will be centered and fit the whole window. 

When fitting all views a unique zoom is computed for all the views. All views are on the same scale. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# fit only view 1 
fit 1 
# fit all 2d views 
2dfit 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
See also: **zoom**, **mu**, **pu** 


@subsubsection occt_draw_4_1_6 u, d, l, r

Syntax:      

~~~~~
u [index] 
d [index] 
l [index] 
r [index] 
~~~~~

**u**, **d**, **l**, **r** Rotate the object in view around its axis by five degrees up, down, left or right respectively. This command is restricted to axonometric and perspective views. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# rotate the view up 
u 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_4_1_7 focal, fu, fd

Syntax:                  
~~~~~
focal [f] 
fu [index] 
fd [index] 
~~~~~

* **focal** changes the vantage point in perspective views. A low f value increases the perspective effect; a high one give a perspective similar to that of an axonometric view. The default value is 500. 
* **fu** and **fd** increase or decrease the focal value by 10%. **fd** makes the eye closer to the object. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
pers 
repeat 10 fd 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

**Note**: Do not use a negative or null focal value. 

See also: **pers** 

@subsubsection occt_draw_4_1_8 color

Syntax: 

~~~~~
color index name 
~~~~~

**color** sets the color to a value. The index of the *color* is a value between 0 and 15. The name is an X window color name. The list of these can be found in the file *rgb.txt* in the X library directory. 

The default values are: 0 White, 1 Red, 2 Green, 3 Blue, 4 Cyan, 5 Gold, 6 Magenta, 7 Marron, 8 Orange, 9 Pink, 10 Salmon, 11 Violet, 12 Yellow, 13 Khaki, 14 Coral. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# change the value of blue 
color 3 "navy blue" 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


**Note** that the color change will be visible on the next redraw of the views, for example, after *fit* or *mu*, etc. 

@subsubsection occt_draw_4_1_9 dtext

Syntax:      
~~~~~
dtext [x y [z]] string 
~~~~~

**dtext** displays a string in all 3d or 2d views. If no coordinates are given, a graphic selection is required. If two coordinates are given, the text is created in a 2d view at the position specified. With 3 coordinates, the text is created in a 3d view. 

The coordinates are real space coordinates. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# mark the origins 
dtext 0 0 bebop 
dtext 0 0 0 bebop 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_4_1_10 hardcopy, hcolor, xwd

Syntax:      
~~~~~
hardcopy [index] 
hcolor index width gray 
xwd [index] filename 
~~~~~

* **hardcopy** creates a postcript file called a4.ps in the current directory. This file contains the postscript description of the view index, and will allow you to print the view. 
* **hcolor** lets you change the aspect of lines in the postscript file. It allows to specify a width and a gray level for one of the 16 colors. **width** is measured in points with default value as 1, **gray** is the gray level from 0 = black to 1 = white with default value as 0. All colors are bound to the default values at the beginning. 
* **xwd** creates an X window xwd file from an active view. By default, the index is set to1. To visualize an xwd file, use the unix command **xwud**. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# all blue lines (color 3) 
# will be half-width and gray 
hcolor 3 0.5 

# make a postscript file and print it 
hardcopy 
lpr a4.ps 

# make an xwd file and display it 
xwd theview 
xwud -in theview 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

**Note:** When more than one view is present, specify the index of the view. 

Only use a postscript printer to print postscript files. 

See also: **color** 


@subsubsection occt_draw_4_1_11 wclick, pick

Syntax:      
~~~~~
wclick 
pick index X Y Z b [nowait] 
~~~~~

**wclick** defers an event until the mouse button is clicked. The message <code>just click</code> is displayed. 

Use the **pick** command to get graphic input. The arguments must be names for variables where the results are stored. 
  * index: index of the view where the input was made.
  * X,Y,Z: 3d coordinates in real world.
  * b: b is the mouse button 1,2 or 3.

When there is an extra argument, its value is not used and the command does not wait for a click; the value of b may then be 0 if there has not been a click. 

This option is useful for tracking the pointer. 

**Note** that the results are stored in Draw numeric variables.

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# make a circle at mouse location 
pick index x y z b 
circle c x y z 0 0 1 1 0 0 0 30 

# make a dynamic circle at mouse location 
# stop when a button is clicked 
# (see the repaint command) 

dset b 0 
while {[dval b] == 0} { 
pick index x y z b nowait 
circle c x y z 0 0 1 1 0 0 0 30 
repaint 
} 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
See also: **repaint** 


Draw provides commands to manage the display of objects. 
* **display**, **donly** are used to display, 
* **erase**, **clear**, **2dclear** to erase. 
* **autodisplay** command is used to check whether variables are displayed when created. 

The variable name "." (dot) has a special status in Draw. Any Draw command expecting a Draw object as argument can be passed a dot. The meaning of the dot is the following. 
  * If the dot is an input argument, a graphic selection will be made. Instead of getting the object from a variable, Draw will ask you to select an object in a view.
  * If the dot is an output argument, an unnamed object will be created. Of course this makes sense only for graphic objects: if you create an unnamed number you will not be able to access it. This feature is used when you want to create objects for display only.
  * If you do not see what you expected while executing loops or sourcing files, use the **repaint** and **dflush** commands.

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# OK use dot to dump an object on the screen 
dump . 

point . x y z 

#Not OK. display points on a curve c 
# with dot no variables are created 
for {set i 0} {$i = 10} {incr i} { 
cvalue c $i/10 x y z 
point . x y z 
} 

# point p x y z 
# would have displayed only one point 
# because the precedent variable content is erased 

# point p$i x y z 
# is an other solution, creating variables 
# p0, p1, p2, .... 

# give a name to a graphic object 
rename . x 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


@subsubsection occt_draw_4_1_12 autodisplay

Syntax:      

~~~~~
autodisplay [0/1] 
~~~~~

By default, Draw automatically displays any graphic object as soon as it is created. This behavior known as autodisplay can be removed with the command **autodisplay**. Without arguments, **autodisplay** toggles the autodisplay mode. The command always returns the current mode. 

When **autodisplay** is off, using the dot return argument is ineffective. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# c is displayed 
circle c 0 0 1 0 5 

# toggle the mode 
autodisplay 
== 0 
circle c 0 0 1 0 5 

# c is erased, but not displayed 
display c 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_4_1_13 display, donly

Syntax:      
~~~~~
display varname [varname ...] 
donly varname [varname ...] 
~~~~~

* **display** makes objects visible. 
* **donly** *display only* makes objects visible and erases all other objects. It is very useful to extract one object from a messy screen. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
\# to see all objects 
foreach var [directory] {display $var} 

\# to select two objects and erase the other ones 
donly . . 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


@subsubsection occt_draw_4_1_14 erase, clear, 2dclear

Syntax:      

~~~~~
erase [varname varname ...] 
clear 
2dclear 
~~~~~

**erase** removes objects from all views. **erase** without arguments erases everything in 2d and 3d. 

**clear** erases only 3d objects and **2dclear** only 2d objects. **erase** without arguments is similar to  **clear; 2dclear**.


**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
# erase eveerything with a name starting with c_ 
foreach var [directory c_*] {erase $var} 

# clear 2d views 
2dclear 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_4_1_15 repaint, dflush


Syntax:

~~~~~
repaint 
dflush 
~~~~~

* **repaint** forces repainting of views. 
* **dflush** flushes the graphic buffers. 

These commands are useful within loops or in scripts. 

When an object is modified or erased, the whole view must be repainted. To avoid doing this too many times, Draw sets up a flag and delays the repaint to the end of the command in which the new prompt is issued. In a script, you may want to display the result of a change immediately. If the flag is raised, **repaint** will repaint the views and clear the flag. 

Graphic operations are buffered by Draw (and also by the X system). Usually the buffer is flushed at the end of a command and before graphic selection. If you want to flush the buffer from inside a script, use the **dflush** command. 

See also: <a href="#occt_draw_4_1_11">pick</a> command.  

@subsection occt_draw_4_2 AIS viewer – view commands

@subsubsection occt_draw_4_2_1 vinit

Syntax:                  
~~~~~
vinit 
~~~~~
Creates the 3D viewer window 

@subsubsection occt_draw_4_2_2 vhelp

Syntax:
~~~~~
vhelp 
~~~~~
Displays help in the 3D viewer window. The help consists in a list of hotkeys and their functionalities. 

@subsubsection occt_draw_4_2_3 vtop

Syntax:
~~~~~
vtop 
~~~~~

Displays top view in the 3D viewer window. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
vinit 
box b 10 10 10 
vdisplay b 
vfit 
vtop 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_4_2_4 vaxo

Syntax:                  
~~~~~
vaxo 
~~~~~

Displays axonometric view in the 3D viewer window. 

**Example:** 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
vinit 
box b 10 10 10 
vdisplay b 
vfit 
vaxo 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@subsubsection occt_draw_4_2_5 vsetbg

Syntax:                  
~~~~~
vsetbg imagefile [filltype] 
~~~~~

Loads image file as background. *filltype* must be NONE, CENTERED, TILED or STRETCH. 

**Example:** 
~~~~~
vinit 
vsetbg myimage.brep CENTERED 
~~~~~

@subsubsection occt_draw_4_2_6 vclear

Syntax:                  
~~~~~
vclear 
~~~~~
Removes all objects from the viewer. 

@subsubsection occt_draw_4_2_7 vrepaint

Syntax:                  
~~~~~
vrepaint 
~~~~~
Forcedly redisplays the shape in the 3D viewer window. 

@subsubsection occt_draw_4_2_8 vfit

Syntax:                  
~~~~~
vfit 
~~~~~
Automatic zoom/panning. Objects in the view are visualized to occupy the maximum surface. 

@subsubsection occt_draw_4_2_9 vzfit

Syntax:                  
~~~~~
vzfit 
~~~~~

Automatic depth panning. Objects in the view are visualized to occupy the maximum 3d space. 

@subsubsection occt_draw_4_2_10  vreadpixel

Syntax:     
~~~~~
vreadpixel xPixel yPixel [{rgb|rgba|depth|hls|rgbf|rgbaf}=rgba] [name] 
~~~~~
Read pixel value for active view.


@subsubsection occt_draw_4_2_11  vselect

Syntax:     
~~~~~
vselect x1 y1 [x2 y2 [x3 y3 ... xn yn]] [shift_selection = 0|1]
~~~~~

Emulates different types of selection:

  * single mouse click selection
  * selection with a rectangle having the upper left and bottom right corners in <i>(x1,y1)</i> and <i>(x2,y2)</i> respectively
  * selection with a polygon having the corners in pixel positions <i>(x1,y1), (x2,y2),…, (xn,yn)</i>
  * any of these selections if shift_selection is set to 1.

@subsubsection occt_draw_4_2_12  vmoveto

Syntax:     

~~~~~
vmoveto x y
~~~~~
Emulates cursor movement to pixel position (x,y).

@subsubsection occt_draw_4_2_13  vviewparams

Syntax:     
~~~~~
vviewparams [scale center_X center_Y proj_X proj_Y proj_Z up_X up_Y up_Z at_X at_Y at_Z]
~~~~~
Gets or sets the current view characteristics.

@subsubsection occt_draw_4_2_14  vchangeselected

Syntax:     
~~~~~
vchangeselected shape
~~~~~
Adds a shape to selection or removes one from it.

@subsubsection occt_draw_4_2_15  vzclipping

Syntax:     
~~~~~
vzclipping [mode] [depth width]
~~~~~
Gets or sets ZClipping mode, width and depth, where
 - *mode = OFF|BACK|FRONT|SLICE*
 - *depth* is a real value from segment [0,1]
 - *width* is a real value from segment [0,1]

@subsubsection occt_draw_4_2_16  vnbselected

Syntax:     
~~~~~
vnbselected
~~~~~
Returns the number of selected objects in the interactive context.

@subsubsection occt_draw_4_2_17  vantialiasing

Syntax:     
~~~~~
valntialiasing 1|0
~~~~~
Sets antialiasing if the command is called with 1 or unsets otherwise.

@subsubsection occt_draw_4_2_18  vpurgedisplay

Syntax:     
~~~~~
vpurgedisplay [CollectorToo = 0|1]
~~~~~
Removes structures which do not belong to objects displayed in neutral point.

@subsubsection occt_draw_4_2_19  vhlr

Syntax:     
~~~~~
vhlr is_enabled={on|off}
~~~~~
Switches hidden line removal (computed) mode on/off.

@subsubsection occt_draw_4_2_20  vhlrtype

Syntax:     
~~~~~
vhlrtype  algo_type={algo|polyalgo} [shape_1 ... shape_n]
~~~~~

Changes the type of HLR algorithm used for shapes.
If the algo_type is algo, the exact HLR algorithm is used, otherwise the polygonal algorithm is used for defined shapes. 

If no shape is specified through the command arguments, the given HLR algorithm_type is applied to all *AIS_Shape* isntances in the current context, and the command also changes the default HLR algorithm type.

**Note** that this command works with instances of *AIS_Shape* or derived classes only, other interactive object types are ignored.


@subsection occt_draw_4_3 AIS viewer – display commands

@subsubsection occt_draw_4_3_1 vdisplay

Syntax: 
~~~~~                 
vdisplay name1 [name2] … [name n] 
~~~~~

Displays named objects. 

**Example:** 
~~~~~ 
vinit 
box b 40 40 40 10 10 10 
psphere s 20 
vdisplay s b 
vfit 
~~~~~ 

@subsubsection occt_draw_4_3_2 vdonly

Syntax:                  
~~~~~
vdonly [name1] … [name n]
~~~~~ 

Displays only selected or named objects. If there are no selected or named objects, nothing is done. 

**Example:** 
~~~~~ 
vinit 
box b 40 40 40 10 10 10 
psphere s 20 
vdonly b 
vfit
~~~~~ 
 
@subsubsection occt_draw_4_3_3 vdisplayall

Syntax:                  
~~~~~ 
vdisplayall 
~~~~~ 

Displays all created objects. 

**Example:** 
~~~~~ 
vinit 
box b 40 40 40 10 10 10 
psphere s 20 
vdisplayall 
vfit 
~~~~~ 

@subsubsection occt_draw_4_3_4 verase

Syntax:                  
~~~~~
verase [name1] [name2] … [name n]
~~~~~ 

Erases some selected or named objects. If there are no selected or named objects, the whole viewer is erased. 

**Example:** 
~~~~~
vinit 
box b1 40 40 40 10 10 10 
box b2 -40 -40 -40 10 10 10 
psphere s 20 
vdisplayall 
vfit 
# erase only first box 
verase b1 
# erase second box and sphere 
verase
~~~~~ 

@subsubsection occt_draw_4_3_5 veraseall

Syntax:                  
~~~~~
veraseall
~~~~~ 

Erases all objects displayed in the viewer. 

**Example:**
~~~~~ 
vinit 
box b1 40 40 40 10 10 10 
box b2 -40 -40 -40 10 10 10 
psphere s 20 
vdisplayall 
vfit 
# erase only first box 
verase b1 
# erase second box and sphere 
verseall
~~~~~ 

@subsubsection occt_draw_4_3_6 vsetdispmode

Syntax:                  
~~~~~
vsetdispmode [name] mode(0,1,2,3)
~~~~~ 

Sets display mode for all, selected or named objects. 
* *0* (*WireFrame*), 
* *1* (*Shading*), 
* *2* (*Quick HideLineremoval*), 
* *3* (*Exact HideLineremoval*). 

**Example:** 
~~~~~
vinit 
box b 10 10 10 
vdisplay b 
vsetdispmode 1 
vfit
~~~~~
 
@subsubsection occt_draw_4_3_7 vdisplaytype

Syntax:                  
~~~~~
vdisplaytype type
~~~~~ 

Displays all objects of a given type. 
The following types are possible: *Point*, *Axis*, *Trihedron*, *PlaneTrihedron*, *Line*, *Circle*, *Plane*, *Shape*, *ConnectedShape*, *MultiConn.Shape*, *ConnectedInter.*, *MultiConn.*, *Constraint* and *Dimension*. 

@subsubsection occt_draw_4_3_8 verasetype

Syntax:                  
~~~~~
verasetype type
~~~~~ 

Erases all objects of a given type. 
Possible type is *Point*, *Axis*, *Trihedron*, *PlaneTrihedron*, *Line*, *Circle*, *Plane*, *Shape*, *ConnectedShape*, *MultiConn.Shape*, *ConnectedInter.*, *MultiConn.*, *Constraint* and *Dimension*. 

@subsubsection occt_draw_4_3_9 vtypes

Syntax:                  
~~~~~
vtypes
~~~~~ 

Makes a list of known types and signatures in AIS. 

@subsubsection occt_draw_4_3_10 vsetcolor

Syntax:                  
~~~~~
vsetcolor [shapename] colorname
~~~~~ 

Sets color for all, selected or named shapes. 
Possible *colorname* is: *BLACK*, *MATRAGRAY*, *MATRABLUE*, *ALICEBLUE*, *ANTIQUEWHITE*, *ANTIQUEWHITE1*, *ANTIQUEWHITE2*, *ANTIQUEWHITE3*, *ANTIQUEWHITE4*, *AQUAMARINE1*, *AQUAMARINE2*, *AQUAMARINE4*, *AZURE*, *AZURE2*, *AZURE3*, *AZURE4*, *BEIGE*, *BISQUE*, *BISQUE2*, *BISQUE3*, *BISQUE4*, *BLANCHEDALMOND*, *BLUE1*, *BLUE2*, *BLUE3*, *BLUE4*, *BLUEVIOLET*, *BROWN*, *BROWN1*, *BROWN2*, *BROWN3*, *BROWN4*, *BURLYWOOD*, *BURLYWOOD1*, *BURLYWOOD2*, *BURLYWOOD3*, *BURLYWOOD4*, *CADETBLUE*, *CADETBLUE1*, *CADETBLUE2*, *CADETBLUE3*, *CADETBLUE4*, *CHARTREUSE*, *CHARTREUSE1*, *CHARTREUSE2*, *CHARTREUSE3*, *CHARTREUSE4*, *CHOCOLATE*, *CHOCOLATE1*, *CHOCOLATE2*, *CHOCOLATE3*, *CHOCOLATE4*, *CORAL*, *CORAL1*, *CORAL2*, *CORAL3*, *CORAL4*, *CORNFLOWERBLUE*, *CORNSILK1*, *CORNSILK2*, *CORNSILK3*, *CORNSILK4*, *CYAN1*, *CYAN2*, *CYAN3*, *CYAN4*, *DARKGOLDENROD*, *DARKGOLDENROD1*, *DARKGOLDENROD2*, *DARKGOLDENROD3*, *DARKGOLDENROD4*, *DARKGREEN*, *DARKKHAKI*, *DARKOLIVEGREEN*, *DARKOLIVEGREEN1*, *DARKOLIVEGREEN2*, *DARKOLIVEGREEN3*, *DARKOLIVEGREEN4*, *DARKORANGE*, *DARKORANGE1*, *DARKORANGE2*, *DARKORANGE3*, *DARKORANGE4*, *DARKORCHID*, *DARKORCHID1*, *DARKORCHID2*, *DARKORCHID3*, *DARKORCHID4*, *DARKSALMON*, *DARKSEAGREEN*, *DARKSEAGREEN1*, *DARKSEAGREEN2*, *DARKSEAGREEN3*, *DARKSEAGREEN4*, *DARKSLATEBLUE*, *DARKSLATEGRAY1*, *DARKSLATEGRAY2*, *DARKSLATEGRAY3*, *DARKSLATEGRAY4*, *DARKSLATEGRAY*, *DARKTURQUOISE*, *DARKVIOLET*, *DEEPPINK*, *DEEPPINK2*, *DEEPPINK3*, *DEEPPINK4*, *DEEPSKYBLUE1*, *DEEPSKYBLUE2*, *DEEPSKYBLUE3*, *DEEPSKYBLUE4*, *DODGERBLUE1*, *DODGERBLUE2*, *DODGERBLUE3*, *DODGERBLUE4*, *FIREBRICK*, *FIREBRICK1*, *FIREBRICK2*, *FIREBRICK3*, *FIREBRICK4*, *FLORALWHITE*, *FORESTGREEN*, *GAINSBORO*, *GHOSTWHITE*, *GOLD*, *GOLD1*, *GOLD2*, *GOLD3*, *GOLD4*, *GOLDENROD*, *GOLDENROD1*, *GOLDENROD2*, *GOLDENROD3*, *GOLDENROD4*, *GRAY*, *GRAY0*, *GRAY1*, *GRAY10*, *GRAY11*, *GRAY12*, *GRAY13*, *GRAY14*, *GRAY15*, *GRAY16*, *GRAY17*, *GRAY18*, *GRAY19*, *GRAY2*, *GRAY20*, *GRAY21*, *GRAY22*, *GRAY23*, *GRAY24*, *GRAY25*, *GRAY26*, *GRAY27*, *GRAY28*, *GRAY29*, *GRAY3*, *GRAY30*, *GRAY31*, *GRAY32*, *GRAY33*, *GRAY34*, *GRAY35*, *GRAY36*, *GRAY37*, *GRAY38*, *GRAY39*, *GRAY4*, *GRAY40*, *GRAY41*, *GRAY42*, *GRAY43*, *GRAY44*, *GRAY45*, *GRAY46*, *GRAY47*, *GRAY48*, *GRAY49*, *GRAY5*, *GRAY50*, *GRAY51*, *GRAY52*, *GRAY53*, *GRAY54*, *GRAY55*, *GRAY56*, *GRAY57*, *GRAY58*, *GRAY59*, *GRAY6*, *GRAY60*, *GRAY61*, *GRAY62*, *GRAY63*, *GRAY64*, *GRAY65*, *GRAY66*, *GRAY67*, *GRAY68*, *GRAY69*, *GRAY7*, *GRAY70*, *GRAY71*, *GRAY72*, *GRAY73*, *GRAY74*, *GRAY75*, *GRAY76*, *GRAY77*, *GRAY78*, *GRAY79*, *GRAY8*, *GRAY80*, *GRAY81*, *GRAY82*, *GRAY83*, *GRAY85*, *GRAY86*, *GRAY87*, *GRAY88*, *GRAY89*, *GRAY9*, *GRAY90*, *GRAY91*, *GRAY92*, *GRAY93*, *GRAY94*, *GRAY95*, *GREEN*, *GREEN1*, *GREEN2*, *GREEN3*, *GREEN4*, *GREENYELLOW*, *GRAY97*, *GRAY98*, *GRAY99*, *HONEYDEW*, *HONEYDEW2*, *HONEYDEW3*, *HONEYDEW4*, *HOTPINK*, *HOTPINK1*, *HOTPINK2*, *HOTPINK3*, *HOTPINK4*, *INDIANRED*, *INDIANRED1*, *INDIANRED2*, *INDIANRED3*, *INDIANRED4*, *IVORY*, *IVORY2*, *IVORY3*, *IVORY4*, *KHAKI*, *KHAKI1*, *KHAKI2*, *KHAKI3*, *KHAKI4*, *LAVENDER*, *LAVENDERBLUSH1*, *LAVENDERBLUSH2*, *LAVENDERBLUSH3*, *LAVENDERBLUSH4*, *LAWNGREEN*, *LEMONCHIFFON1*, *LEMONCHIFFON2*, *LEMONCHIFFON3*, *LEMONCHIFFON4*, *LIGHTBLUE*, *LIGHTBLUE1*, *LIGHTBLUE2*, *LIGHTBLUE3*, *LIGHTBLUE4*, *LIGHTCORAL*, *LIGHTCYAN1*, *LIGHTCYAN2*, *LIGHTCYAN3*, *LIGHTCYAN4*, *LIGHTGOLDENROD*, *LIGHTGOLDENROD1*, *LIGHTGOLDENROD2*, *LIGHTGOLDENROD3*, *LIGHTGOLDENROD4*, *LIGHTGOLDENRODYELLOW*, *LIGHTGRAY*, *LIGHTPINK*, *LIGHTPINK1*, *LIGHTPINK2*, *LIGHTPINK3*, *LIGHTPINK4*, *LIGHTSALMON1*, *LIGHTSALMON2*, *LIGHTSALMON3*, *LIGHTSALMON4*, *LIGHTSEAGREEN*, *LIGHTSKYBLUE*, *LIGHTSKYBLUE1*, *LIGHTSKYBLUE2*, *LIGHTSKYBLUE3*, *LIGHTSKYBLUE4*, *LIGHTSLATEBLUE*, *LIGHTSLATEGRAY*, *LIGHTSTEELBLUE*, *LIGHTSTEELBLUE1*, *LIGHTSTEELBLUE2*, *LIGHTSTEELBLUE3*, *LIGHTSTEELBLUE4*, *LIGHTYELLOW*, *LIGHTYELLOW2*, *LIGHTYELLOW3*, *LIGHTYELLOW4*, *LIMEGREEN*, *LINEN*, *MAGENTA1*, *MAGENTA2*, *MAGENTA3*, *MAGENTA4*, *MAROON*, *MAROON1*, *MAROON2*, *MAROON3*, *MAROON4*, *MEDIUMAQUAMARINE*, *MEDIUMORCHID*, *MEDIUMORCHID1*, *MEDIUMORCHID2*, *MEDIUMORCHID3*, *MEDIUMORCHID4*, *MEDIUMPURPLE*, *MEDIUMPURPLE1*, *MEDIUMPURPLE2*, *MEDIUMPURPLE3*, *MEDIUMPURPLE4*, *MEDIUMSEAGREEN*, *MEDIUMSLATEBLUE*, *MEDIUMSPRINGGREEN*, *MEDIUMTURQUOISE*, *MEDIUMVIOLETRED*, *MIDNIGHTBLUE*, *MINTCREAM*, *MISTYROSE*, *MISTYROSE2*, *MISTYROSE3*, *MISTYROSE4*, *MOCCASIN*, *NAVAJOWHITE1*, *NAVAJOWHITE2*, *NAVAJOWHITE3*, *NAVAJOWHITE4*, *NAVYBLUE*, *OLDLACE*, *OLIVEDRAB*, *OLIVEDRAB1*, *OLIVEDRAB2*, *OLIVEDRAB3*, *OLIVEDRAB4*, *ORANGE*, *ORANGE1*, *ORANGE2*, *ORANGE3*, *ORANGE4*, *ORANGERED*, *ORANGERED1*, *ORANGERED2*, *ORANGERED3*, *ORANGERED4*, *ORCHID*, *ORCHID1*, *ORCHID2*, *ORCHID3*, *ORCHID4*, *PALEGOLDENROD*, *PALEGREEN*, *PALEGREEN1*, *PALEGREEN2*, *PALEGREEN3*, *PALEGREEN4*, *PALETURQUOISE*, *PALETURQUOISE1*, *PALETURQUOISE2*, *PALETURQUOISE3*, *PALETURQUOISE4*, *PALEVIOLETRED*, *PALEVIOLETRED1*, *PALEVIOLETRED2*, *PALEVIOLETRED3*, *PALEVIOLETRED4*, *PAPAYAWHIP*, *PEACHPUFF*, *PEACHPUFF2*, *PEACHPUFF3*, *PEACHPUFF4*, *PERU*, *PINK*, *PINK1*, *PINK2*, *PINK3*, *PINK4*, *PLUM*, *PLUM1*, *PLUM2*, *PLUM3*, *PLUM4*, *POWDERBLUE*, *PURPLE*, *PURPLE1*, *PURPLE2*, *PURPLE3*, *PURPLE4*, *RED*, *RED1*, *RED2*, *RED3*, *RED4*, *ROSYBROWN*, *ROSYBROWN1*, *ROSYBROWN2*, *ROSYBROWN3*, *ROSYBROWN4*, *ROYALBLUE*, *ROYALBLUE1*, *ROYALBLUE2*, *ROYALBLUE3*, *ROYALBLUE4*, *SADDLEBROWN*, *SALMON*, *SALMON1*, *SALMON2*, *SALMON3*, *SALMON4*, *SANDYBROWN*, *SEAGREEN*, *SEAGREEN1*, *SEAGREEN2*, *SEAGREEN3*, *SEAGREEN4*, *SEASHELL*, *SEASHELL2*, *SEASHELL3*, *SEASHELL4*, *BEET*, *TEAL*, *SIENNA*, *SIENNA1*, *SIENNA2*, *SIENNA3*, *SIENNA4*, *SKYBLUE*, *SKYBLUE1*, *SKYBLUE2*, *SKYBLUE3*, *SKYBLUE4*, *SLATEBLUE*, *SLATEBLUE1*, *SLATEBLUE2*, *SLATEBLUE3*, *SLATEBLUE4*, *SLATEGRAY1*, *SLATEGRAY2*, *SLATEGRAY3*, *SLATEGRAY4*, *SLATEGRAY*, *SNOW*, *SNOW2*, *SNOW3*, *SNOW4*, *SPRINGGREEN*, *SPRINGGREEN2*, *SPRINGGREEN3*, *SPRINGGREEN4*, *STEELBLUE*, *STEELBLUE1*, *STEELBLUE2*, *STEELBLUE3*, *STEELBLUE4*, *TAN*, *TAN1*, *TAN2*, *TAN3*, *TAN4*, *THISTLE*, *THISTLE1*, *THISTLE2*, *THISTLE3*, *THISTLE4*, *TOMATO*, *TOMATO1*, *TOMATO2*, *TOMATO3*, *TOMATO4*, *TURQUOISE*, *TURQUOISE1*, *TURQUOISE2*, *TURQUOISE3*, *TURQUOISE4*, *VIOLET*, *VIOLETRED*, *VIOLETRED1*, *VIOLETRED2*, *VIOLETRED3*, *VIOLETRED4*, *WHEAT*, *WHEAT1*, *WHEAT2*, *WHEAT3*, *WHEAT4*, *WHITE*, *WHITESMOKE*, *YELLOW*, *YELLOW1*, *YELLOW2*, *YELLOW3*, *YELLOW4* and *YELLOWGREEN*.

@subsubsection occt_draw_4_3_11 vunsetcolor

Syntax:                  
~~~~~
vunsetcolor [shapename]
~~~~~ 

Sets default color for all, selected or named shapes. 

@subsubsection occt_draw_4_3_12 vsettransparency

Syntax:                  
~~~~~
vsettransparency [shapename] coeficient
~~~~~ 

Sets transparency for all selected or named shapes. The *coefficient* may be between 0.0 (opaque) and 1.0 (fully transparent). 

**Warning**: at 1.0 the shape becomes invisible.
 
**Example:** 
~~~~~
vinit 
box b 10 10 10 
psphere s 20 
vdisplay b s 
vfit 
vsetdispmode 1 
vsettransparency b 0.5
~~~~~ 

@subsubsection occt_draw_4_3_13 vunsettransparency

Syntax:                  
~~~~~
vunsettransparency [shapename]
~~~~~ 

Sets default transparency (0.0) for all selected or named shapes. 

@subsubsection occt_draw_4_3_14 vsetmaterial

Syntax:                  
~~~~~
vsetmaterial [shapename] materialname
~~~~~ 

Sets material for all selected or named shapes. 

**materialname** can be *BRASS*, *BRONZE*, *COPPER*, *GOLD*, *PEWTER*, *PLASTER*, *PLASTIC*, *SILVER*, *STEEL*, *STONE*, *SHINY_PLASTIC*, *SATIN*, *METALIZED*, *NEON_GNC*, *CHROME*, *ALUMINIUM*, *OBSIDIAN*, *NEON_PHC* or *JADE*.
 
**Example:** 
~~~~~
vinit 
psphere s 20 
vdisplay s 
vfit 
vsetdispmode 1 
vsetmaterial s JADE 
~~~~~

@subsubsection occt_draw_4_3_15 vunsetmaterial

Syntax:                  
~~~~~
vunsetmaterial [shapename]
~~~~~ 

Sets default material for all selected or named shapes. 

@subsubsection occt_draw_4_3_16 vsetwidth

Syntax:                  
~~~~~
vsetwidth [shapename] coeficient
~~~~~ 

Sets width of the edges for all selected or named shapes. 
The *coefficient* may be between 0.0 and 10.0.
 
**Example:** 
~~~~~
vinit 
box b 10 10 10 
vdisplay b 
vfit 
vsetwidth b 5
~~~~~ 

@subsubsection occt_draw_4_3_17 vunsetwidth

Syntax:                  
~~~~~
vunsetwidth [shapename]
~~~~~ 

Sets default width of edges (0.0) for all selected or named shapes. 

@subsubsection occt_draw_4_3_18 vsetshading

Syntax:                  
~~~~~
vsetshading shapename [coefficient]
~~~~~ 

Sets deflection coefficient that defines the quality of the shape’s representation in the shading mode. Default coefficient is 0.0008. 

**Example:** 
~~~~~
vinit 
psphere s 20 
vdisplay s 
vfit 
vsetdispmode 1 
vsetshading s 0.005
~~~~~
 
@subsubsection occt_draw_4_3_19 vunsetshading

Syntax:                  
~~~~~
vunsetshading [shapename]
~~~~~ 

Sets default deflection coefficient (0.0008) that defines the quality of the shape’s representation in the shading mode. Default coefficient is 0.0008. 

@subsubsection occt_draw_4_3_20 vsetam

Syntax:                  
~~~~~
vsetam [shapename] mode
~~~~~ 

Activates selection mode for all selected or named shapes: 
* *0* for *shape* itself, 
* *1* (*vertices*), 
* *2* (*edges*), 
* *3* (*wires*), 
* *4* (*faces*), 
* *5* (*shells*),
* *6* (*solids*),
* *7* (*compounds*).
 
**Example:** 
~~~~~
vinit 
box b 10 10 10 
vdisplay b 
vfit 
vsetam b 2
~~~~~
 
@subsubsection occt_draw_4_3_21 vunsetam

Syntax:                  
~~~~~
vunsetam
~~~~~ 

Deactivates all selection modes for all shapes. 

@subsubsection occt_draw_4_3_22 vdump

Syntax:                  
~~~~~
vdump <filename>.{png|xwd|bmp}
~~~~~ 

Extracts the contents of the viewer window to a png, XWD or BMP file. 

@subsubsection occt_draw_4_3_23 vdir

Syntax:                  
~~~~~
vdir
~~~~~ 

Displays the list of displayed objects. 

@subsubsection occt_draw_4_3_24 vsub

Syntax:                  
~~~~~
vsub 0/1(on/off)[shapename]
~~~~~ 

Hilights/unhilights named or selected objects which are displayed at neutral state with subintensity color.
 
**Example:** 
~~~~~
vinit 
box b 10 10 10 
psphere s 20 
vdisplay b s 
vfit 
vsetdispmode 1 
vsub b 1
~~~~~ 

@subsubsection occt_draw_4_3_25 vardis

Syntax:                  
~~~~~
vardis
~~~~~ 

Displays active areas (for each activated sensitive entity, one or several 2D bounding boxes are displayed, depending on the implementation of a particular entity). 

@subsubsection occt_draw_4_3_26 varera

Syntax:                  
~~~~~
varera
~~~~~ 

Erases active areas. 

@subsubsection occt_draw_4_3_27 vsensdis

Syntax:                  
~~~~~
vsensdis
~~~~~ 

Displays active entities (sensitive entities of one of the standard types corresponding to active selection modes). 

Standard entity types are those defined in Select3D package: 
  * sensitive box
  * sensitive face
  * sensitive curve
  * sensitive segment
  * sensitive circle
  * sensitive point
  * sensitive triangulation
  * sensitive triangle
Custom (application-defined) sensitive entity types are not processed by this command. 

@subsubsection occt_draw_4_3_28 vsensera

Syntax:                  
~~~~~
vsensera
~~~~~ 

Erases active entities. 

@subsubsection occt_draw_4_3_29 vperf

Syntax:                  
~~~~~
vperf shapename 1/0 (Transformation/Loacation) 1/0 (Primitives sensibles ON/OFF)
~~~~~ 

Tests the animation of an object along a predefined trajectory. 

**Example:** 
~~~~~
vinit 
box b 10 10 10 
psphere s 20 
vdisplay b s 
vfit 
vsetdispmode 0 
vperf b 1 1
~~~~~
 
@subsubsection occt_draw_4_3_30 vr

Syntax:                  
~~~~~
vr filename
~~~~~ 

Reads shape from BREP-format file and displays it in the viewer. 

**Example:** 
~~~~~
vinit 
vr myshape.brep
~~~~~
 
@subsubsection occt_draw_4_3_31 vstate

Syntax:                  
~~~~~
vstate [name1] … [name n]
~~~~~ 

Makes a list of the status (**Displayed** or **Not Displayed**) of some selected or named objects. 


@subsection occt_draw_4_4 AIS viewer – object commands

@subsubsection occt_draw_4_4_1 vtrihedron

Syntax:                  
~~~~~
vtrihedron name [X0] [Y0] [Z0] [Zu] [Zv] [Zw] [Xu] [Xv] [Xw]
~~~~~ 

Creates a new *AIS_Trihedron* object. If no argument is set, the default trihedron (0XYZ) is created.
 
**Example:** 
~~~~~
vinit 
vtrihedron tr
~~~~~ 

@subsubsection occt_draw_4_4_2 vplanetri

Syntax:                  
~~~~~
vplanetri name
~~~~~ 

Creates a plane from a trihedron selection. 


@subsubsection occt_draw_4_4_3 vsize

Syntax:                  
~~~~~
vsize [name] [size]
~~~~~ 

Changes the size of a named or selected trihedron. If the name is not defined: it affects the selected trihedrons otherwise nothing is done. If the value is not defined, it is set to 100 by default.
 
**Example:** 
~~~~~
vinit 
vtrihedron tr1 
vtrihedron tr2 0 0 0 1 0 0 1 0 0 
vsize tr2 400
~~~~~ 

@subsubsection occt_draw_4_4_4 vaxis

Syntax:                  
~~~~~
vaxis name [Xa Ya Za Xb Yb Zb]
~~~~~ 

Creates an axis. If  the values are not defined, an axis is created by interactive selection of two vertices or one edge
 
**Example:** 
~~~~~
vinit 
vtrihedron tr 
vaxis axe1 0 0 0 1 0 0 
~~~~~

@subsubsection occt_draw_4_4_5 vaxispara

Syntax:                  
~~~~~
vaxispara nom
~~~~~ 

Creates an axis by interactive selection of an edge and a vertex. 

@subsubsection occt_draw_4_4_6 vaxisortho

Syntax:                  
~~~~~
vaxisotrho name
~~~~~ 

Creates an axis by interactive selection of an edge and a vertex. The axis will be orthogonal to the selected edge. 

@subsubsection occt_draw_4_4_7 vpoint

Syntax:                  
~~~~~
vpoint name [Xa Ya Za]
~~~~~ 

Creates a point from coordinates. If the values are not defined, a point is created by interactive selection of a vertice or an edge (in the center of the edge). 

**Example:** 
~~~~~
vinit 
vpoint p 0 0 0 
~~~~~

@subsubsection occt_draw_4_4_8 vplane

Syntax:                  
~~~~~
vplane name [AxisName] [PointName] 
vplane name [PointName] [PointName] [PointName] 
vplane name [PlaneName] [PointName]
~~~~~ 

Creates a plane from named or interactively selected entities.
 
**Example:** 
~~~~~
vinit 
vpoint p1 0 50 0 
vaxis axe1 0 0 0 0 0 1 
vtrihedron tr 
vplane plane1 axe1 p1 
~~~~~

@subsubsection occt_draw_4_4_9 vplanepara

Syntax:                  
~~~~~
vplanepara name
~~~~~ 

Creates a plane from interactively selected vertex and face. 

@subsubsection occt_draw_4_4_10 vplaneortho

Syntax:                  
~~~~~
vplaneortho name
~~~~~ 

Creates a plane from interactive selected face and coplanar edge. 

@subsubsection occt_draw_4_4_11 vline

Syntax:                  
~~~~~
vline name [PointName] [PointName] 
vline name [Xa Ya Za Xb Yb Zb]
~~~~~ 

Creates a line from coordinates, named or interactively selected vertices. 

**Example:** 
~~~~~
vinit 
vtrihedron tr 
vpoint p1 0 50 0 
vpoint p2 50 0 0 
vline line1 p1 p2 
vline line2 0 0 0 50 0 1 
~~~~~

@subsubsection occt_draw_4_4_12 vcircle

Syntax:      
~~~~~
vcircle name [PointName PointName PointName IsFilled] 
vcircle name [PlaneName PointName Radius IsFilled] 
~~~~~

Creates a circle from named or interactively selected entities.  Parameter IsFilled is defined as 0 or 1.
 
**Example:** 
~~~~~
vinit 
vtrihedron tr 
vpoint p1 0 50 0 
vpoint p2 50 0 0 
vpoint p3 0 0 0 
vcircle circle1 p1 p2 p3 1
~~~~~ 

@subsubsection occt_draw_4_4_13 vtri2d

Syntax:                  
~~~~~
vtri2d name
~~~~~ 

Creates a plane with a 2D trihedron from an interactively selected face. 

@subsubsection occt_draw_4_4_14 vselmode

Syntax:                  
~~~~~
vselmode [object] mode On/Off
~~~~~ 

Sets the selection mode for an object. If the object value is not defined, the selection mode is set for all displayed objects. 
Value *On* is defined as 1 and *Off* – as 0. 

**Example:** 
~~~~~
vinit 
vpoint p1 0 0 0 
vpoint p2 50 0 0 
vpoint p3 25 40 0 
vtriangle triangle1 p1 p2 p3 
~~~~~

@subsubsection occt_draw_4_4_15 vconnect, vconnectsh

Syntax:                  
~~~~~
vconnect name object Xo Yo Zo Xu Xv Xw Zu Zv Zw 
vconnectsh name shape Xo Yo Zo Xu Xv Xw Zu Zv Zw
~~~~~ 

Creates and displays an object with input location connected to a named entity. 
The difference between these two commands is that the object created by *vconnect* does not support the selection modes different from 0. 

**Example:** 
~~~~~
Vinitvinit 
vpoint p1 0 0 0 
vpoint p2 50 0 0 
vsegment segment p1 p2 
restore CrankArm.brep obj 
vdisplay obj 
vconnectsh new obj 100100100 1 0 0 0 0 1
~~~~~ 

@subsubsection occt_draw_4_4_16 vtriangle

Syntax:                  
~~~~~
vtriangle name PointName PointName PointName
~~~~~ 

Creates and displays a filled triangle from named points. 

**Example:** 
~~~~~
vinit 
vpoint p1 0 0 0 
vpoint p2 50 0 0 
vpoint p3 25 40 0 
vtriangle triangle1 p1 p2 p3
~~~~~ 

@subsubsection occt_draw_4_4_17 vsegment

Syntax:                  
~~~~~
vsegment name PointName PointName 
~~~~~

Creates and displays a segment from named points. 

**Example:** 
~~~~~
Vinit 
vpoint p1 0 0 0 
vpoint p2 50 0 0 
vsegment segment p1 p2 
~~~~~

@subsection occt_draw_4_5 AIS viewer – Mesh Visualization Service

**MeshVS** (Mesh Visualization Service) component provides flexible means of displaying meshes with associated pre- and post- processor data.

@subsubsection occt_draw_4_5_1 meshfromstl

Syntax:                  
~~~~~
meshfromstl meshname file
~~~~~ 

Creates a *MeshVS_Mesh* object based on STL file data. The object will be displayed immediately.
 
**Example:**
~~~~~ 
meshfromstl mesh myfile.stl
~~~~~ 

@subsubsection occt_draw_4_5_2 meshdispmode

Syntax:                  
~~~~~
meshdispmode meshname displaymode
~~~~~ 

Changes the display mode of object **meshname**. The **displaymode** is integer, which can be:
* *1* for *wireframe*, 
* *2* for *shading* mode, or
* *3* for *shrink* mode. 

**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshdispmode mesh 2
~~~~~ 

@subsubsection occt_draw_4_5_3 meshselmode

Syntax:                  
~~~~~
meshselmode meshname selectionmode
~~~~~ 

Changes the selection mode of object **meshname**. The *selectionmode* is integer OR-combination of mode flags. The basic flags are the following: 
* *1* – node selection;
* *2* – 0D elements (not supported in STL); 
* *4* – links (not supported in STL); 
* *8* – faces.
 
**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshselmode mesh 1
~~~~~ 

@subsubsection occt_draw_4_5_4 meshshadcolor

Syntax:                  
~~~~~
meshshadcolor meshname red green blue
~~~~~ 

Changes the face interior color of object **meshname**. The *red*, *green* and *blue* are real values between *0* and *1*.
 
**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshshadcolormode mesh 0.5 0.5 0.5
~~~~~ 

@subsubsection occt_draw_4_5_5 meshlinkcolor

Syntax:                  
~~~~~
meshlinkcolor meshname red green blue
~~~~~ 

Changes the color of face borders for object **meshname**. The *red*, *green* and *blue* are real values between *0* and *1*.
 
**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshlinkcolormode mesh 0.5 0.5 0.5
~~~~~ 

@subsubsection occt_draw_4_5_6 meshmat

Syntax:                  
~~~~~
meshmat meshname material
~~~~~ 

Changes the material of object **meshname**.

*material* is represented with an integer value as follows (equivalent to enumeration *Graphic3d_NameOfMaterial*): 
* *0 – BRASS,* 
* *1 – BRONZE,* 
* *2 - COPPER,* 
* *3 - GOLD,* 
* *4 - PEWTER,* 
* *5 - PLASTER,* 
* *6 - PLASTIC,* 
* *7 - SILVER,* 
* *8 - STEEL,* 
* *9 - STONE,* 
* *10 - SHINY_PLASTIC,* 
* *11 - SATIN,*
* *12 - METALIZED,* 
* *13 - NEON_GNC,* 
* *14 - CHROME,*
* *15 - ALUMINIUM,*
* *16 - OBSIDIAN,* 
* *17 - NEON_PHC,* 
* *18 - JADE,*
* *19 - DEFAULT,* 
* *20 - UserDefined*
 
**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshmat mesh JADE 
~~~~~

@subsubsection occt_draw_4_5_7 meshshrcoef

Syntax:                  
~~~~~
meshshrcoef meshname shrinkcoefficient
~~~~~ 

Changes the value of shrink coefficient used in the shrink mode. In the shrink mode the face is shown as a congruent part of a usual face, so that *shrinkcoefficient* controls the value of this part. The *shrinkcoefficient* is a positive real number.
 
**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshshrcoef mesh 0.05
~~~~~ 

@subsubsection occt_draw_4_5_8 meshshow

Syntax:                  
~~~~~
meshshow meshname
~~~~~ 

Displays **meshname** in the viewer (if it is erased).
 
**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshshow mesh
~~~~~ 

@subsubsection occt_draw_4_5_9 meshhide

Syntax:                  
~~~~~
meshhide meshname
~~~~~ 

Hides **meshname** in the viewer. 

**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshhide mesh
~~~~~ 

@subsubsection occt_draw_4_5_10 meshhidesel

Syntax:                  
~~~~~
meshhidesel meshname
~~~~~ 

Hides only selected entities. The other part of **meshname** remains visible. 

@subsubsection occt_draw_4_5_11 meshshowsel

Syntax:                  
~~~~~
meshshowsel meshname
~~~~~ 

Shows only selected entities. The other part of **meshname** becomes invisible. 

@subsubsection occt_draw_4_5_12 meshshowall

Syntax:                  
~~~~~
meshshowall meshname
~~~~~ 

Changes the state of all entities to visible for **meshname**. 

@subsubsection occt_draw_4_5_13 meshdelete

Syntax:                  
~~~~~
meshdelete meshname
~~~~~ 

Deletes MeshVS_Mesh object **meshname**. 

**Example:** 
~~~~~
vinit 
meshfromstl mesh myfile.stl 
meshdelete mesh 
~~~~~

@section occt_draw_5 OCAF commands


This chapter contains a set of commands for Open CASCADE Technology Application Framework (OCAF). 


@subsection occt_draw_5_1 Application commands


@subsubsection occt_draw_5_1_1 NewDocument

Syntax:       
~~~~~
NewDocument docname [format]
~~~~~ 

Creates a new **docname** document with MDTV-Standard or described format. 

**Example:** 
~~~~~
# Create new document with default (MDTV-Standard) format 
NewDocument D 

# Create new document with BinOcaf format 
NewDocument D2 BinOcaf 
~~~~~

@subsubsection occt_draw_5_1_2 IsInSession

Syntax:       
~~~~~
IsInSession path
~~~~~ 

Returns *0*, if **path** document is managed by the application session, *1* – otherwise. 

**Example:** 
~~~~~
IsInSession /myPath/myFile.std 
~~~~~

@subsubsection occt_draw_5_1_3 ListDocuments

Syntax:       
~~~~~
ListDocuments
~~~~~ 

Makes a list of documents handled during the session of the application. 


@subsubsection occt_draw_5_1_4 Open

Syntax:       
~~~~~
Open path docname
~~~~~ 

Retrieves the document of file **docname** in the path **path**. Overwrites the document, if it is already in session. 

**Example:** 
~~~~~
Open /myPath/myFile.std D
~~~~~ 

@subsubsection occt_draw_5_1_5 Close

Syntax:       
~~~~~
Close docname
~~~~~ 

Closes **docname** document. The document is no longer handled by the applicative session. 

**Example:** 
~~~~~
Close D 
~~~~~

@subsubsection occt_draw_5_1_6 Save

Syntax:       
~~~~~
Save docname
~~~~~ 

Saves **docname** active document. 

**Example:** 
~~~~~
Save D 
~~~~~

@subsubsection occt_draw_5_1_7 SaveAs

Syntax:       
~~~~~
SaveAs docname path
~~~~~ 

Saves the active document in the file **docname** in the path **path**. Overwrites the file if it already exists. 

**Example:** 
~~~~~
SaveAs D /myPath/myFile.std
~~~~~ 

@subsection occt_draw_5_2 Basic commands

@subsubsection occt_draw_5_2_1 Label

Syntax:   

~~~~~
Label docname entry
~~~~~

Creates the label expressed by <i>\<entry\></i> if it does not exist.

Example
~~~~~
Label D 0:2
~~~~~

@subsubsection occt_draw_5_2_2 NewChild

Syntax:   

~~~~~
NewChild docname [taggerlabel = Root label]
~~~~~
Finds (or creates) a *TagSource* attribute located at father label of <i>\<taggerlabel\></i> and makes a new child label.

Example
~~~~~
# Create new child of root label
NewChild D

# Create new child of existing label
Label D 0:2
NewChild D 0:2
~~~~~

@subsubsection occt_draw_5_2_3 Children

Syntax:  
~~~~~
Children docname label
~~~~~
Returns the list of attributes of label.

Example
~~~~~
Children D 0:2
~~~~~

@subsubsection occt_draw_5_2_4 ForgetAll

Syntax:   
~~~~~
ForgetAll docname label
~~~~~
Forgets all attributes of the label.

Example
~~~~~
ForgetAll D 0:2
~~~~~


@subsubsection occt_draw_5_3 Application commands

@subsubsection occt_draw_5_3_1  Main

Syntax:       
~~~~~
Main docname
~~~~~ 

Returns the main label of the framework. 

**Example:** 
~~~~~
Main D 
~~~~~

@subsubsection occt_draw_5_3_2  UndoLimit

Syntax:       
~~~~~
UndoLimit docname [value=0]
~~~~~ 


Sets the limit on the number of Undo Delta stored. **0** will disable Undo on the document. A negative *value* means that there is no limit. Note that by default Undo is disabled. Enabling it will take effect with the next call to *NewCommand*. Of course, this limit is the same for Redo 

**Example:** 
~~~~~
UndoLimit D 100 
~~~~~

@subsubsection occt_draw_5_3_3  Undo

Syntax:       
~~~~~
Undo docname [value=1]
~~~~~ 

Undoes **value** steps. 

**Example:** 
~~~~~
Undo D 
~~~~~

@subsubsection occt_draw_5_3_4  Redo

Syntax:       
~~~~~
Redo docname [value=1]
~~~~~ 

Redoes **value** steps.
 
**Example:** 
~~~~~
Redo D 
~~~~~

@subsubsection occt_draw_5_3_5  OpenCommand

Syntax:       
~~~~~
OpenCommand docname
~~~~~ 

Opens a new command transaction. 

**Example:**
~~~~~ 
OpenCommand D
~~~~~ 

@subsubsection occt_draw_5_3_6  CommitCommand

Syntax:       
~~~~~
CommitCommand docname
~~~~~ 

Commits the Command transaction. 

**Example:** 
~~~~~
CommitCommand D
~~~~~ 

@subsubsection occt_draw_5_3_7  NewCommand

Syntax:       
~~~~~
NewCommand docname
~~~~~ 

This is a short-cut for Commit and Open transaction. 

**Example:** 
~~~~~
NewCommand D 
~~~~~

@subsubsection occt_draw_5_3_8  AbortCommand

Syntax:       
~~~~~
AbortCommand docname
~~~~~ 

Aborts the Command transaction. 

**Example:** 
~~~~~
AbortCommand D 
~~~~~

@subsubsection occt_draw_5_3_9  Copy

Syntax:       
~~~~~
Copy docname entry Xdocname Xentry
~~~~~ 

Copies the contents of *entry* to *Xentry*. No links are registered. 

**Example:** 
~~~~~
Copy D1 0:2 D2 0:4 
~~~~~

@subsubsection occt_draw_5_3_10  UpdateLink

Syntax:       
~~~~~
UpdateLink docname [entry] 
~~~~~

Updates external reference set at *entry*. 

**Example:** 
~~~~~
UpdateLink D 
~~~~~

@subsubsection occt_draw_5_3_11  CopyWithLink

Syntax:       
~~~~~
CopyWithLink docname entry Xdocname Xentry
~~~~~ 

Aborts the Command transaction. 
Copies the content of *entry* to *Xentry*. The link is registered with an *Xlink* attribute at *Xentry*  label. 

**Example:** 
~~~~~
CopyWithLink D1 0:2 D2 0:4
~~~~~ 

@subsubsection occt_draw_5_3_12  UpdateXLinks

Syntax:       
~~~~~
UpdateXLinks docname entry
~~~~~ 

Sets modifications on labels impacted by external references to the *entry*. The *document* becomes invalid and must be recomputed 

**Example:** 
~~~~~
UpdateXLinks D 0:2 
~~~~~

@subsubsection occt_draw_5_3_13  DumpDocument

Syntax:       
~~~~~
DumpDocument docname
~~~~~ 

Displays parameters of *docname* document. 

**Example:** 
~~~~~
DumpDocument D 
~~~~~


@subsection occt_draw_5_4  Data Framework commands


@subsubsection occt_draw_5_4_1  MakeDF

Syntax:       
~~~~~
MakeDF dfname
~~~~~ 

Creates a new data framework. 

**Example:** 
~~~~~
MakeDF D 
~~~~~

@subsubsection occt_draw_5_4_2  ClearDF

Syntax:       
~~~~~
ClearDF dfname
~~~~~ 

Clears a data framework. 

**Example:** 
~~~~~
ClearDF D 
~~~~~

@subsubsection occt_draw_5_4_3  CopyDF

Syntax:       
~~~~~
CopyDF dfname1 entry1 [dfname2] entry2
~~~~~ 

Copies a data framework. 

**Example:** 
~~~~~
CopyDF D 0:2 0:4 
~~~~~

@subsubsection occt_draw_5_4_4  CopyLabel

Syntax:       
~~~~~
CopyLabel dfname fromlabel tolablel
~~~~~ 

Copies a label. 

**Example:** 
~~~~~
CopyLabel D1 0:2 0:4 
~~~~~

@subsubsection occt_draw_5_4_5  MiniDumpDF

Syntax:       
~~~~~
MiniDumpDF dfname
~~~~~ 

Makes a mini-dump of a data framework. 

**Example:** 
~~~~~
MiniDumpDF D 
~~~~~

@subsubsection occt_draw_5_4_6  XDumpDF

Syntax:       
~~~~~
XDumpDF dfname
~~~~~ 

Makes an extended dump of a data framework. 

**Example:** 
~~~~~
XDumpDF D
~~~~~ 

@subsection occt_draw_5_5  General attributes commands


@subsubsection occt_draw_5_5_1  SetInteger

Syntax:       
~~~~~
SetInteger dfname entry value
~~~~~ 

Finds or creates an Integer attribute at *entry* label and sets *value*. 

**Example:** 
~~~~~
SetInteger D 0:2 100 
~~~~~

@subsubsection occt_draw_5_5_2  GetInteger

Syntax:       
~~~~~
GetInteger dfname entry [drawname]
~~~~~ 

Gets a value of an Integer attribute at *entry* label and sets it to *drawname* variable, if it is defined. 

**Example:** 
~~~~~
GetInteger D 0:2 Int1 
~~~~~

@subsubsection occt_draw_5_5_3  SetReal

Syntax:       
~~~~~
SetReal dfname entry value
~~~~~ 

Finds or creates a Real attribute at *entry* label and sets *value*. 

**Example:** 
~~~~~
SetReal D 0:2 100. 
~~~~~

@subsubsection occt_draw_5_5_4  GetReal

Syntax:       
~~~~~
GetReal dfname entry [drawname]
~~~~~ 

Gets a value of a Real attribute at *entry* label and sets it to *drawname* variable, if it is defined. 

**Example:** 
~~~~~
GetReal D 0:2 Real1 
~~~~~

@subsubsection occt_draw_5_5_5  SetIntArray

Syntax:       
~~~~~
SetIntArray dfname entry lower upper value1 value2 … 
~~~~~

Finds or creates an IntegerArray attribute at *entry* label with lower and upper bounds and sets **value1*, *value2*... 

**Example:** 
~~~~~
SetIntArray D 0:2 1 4 100 200 300 400
~~~~~ 

@subsubsection occt_draw_5_5_6  GetIntArray

Syntax:       
~~~~~
GetIntArray dfname entry
~~~~~ 

Gets a value of an *IntegerArray* attribute at *entry* label. 

**Example:** 
~~~~~
GetIntArray D 0:2
~~~~~ 

@subsubsection occt_draw_5_5_7  SetRealArray

Syntax:       
~~~~~
SetRealArray dfname entry lower upper value1 value2 …
~~~~~ 

Finds or creates a RealArray attribute at *entry* label with lower and upper bounds and sets *value1*, *value2*… 

**Example:** 
~~~~~
GetRealArray D 0:2 1 4 100. 200. 300. 400. 
~~~~~

@subsubsection occt_draw_5_5_8  GetRealArray

Syntax:       
~~~~~
GetRealArray dfname entry
~~~~~ 

Gets a value of a RealArray attribute at *entry* label. 

**Example:** 
~~~~~
GetRealArray D 0:2 
~~~~~

@subsubsection occt_draw_5_5_9  SetComment

Syntax:       
~~~~~
SetComment dfname entry value
~~~~~ 

Finds or creates a Comment attribute at *entry* label and sets *value*. 

**Example:** 
~~~~~
SetComment D 0:2 "My comment"
~~~~~ 

@subsubsection occt_draw_5_5_10  GetComment

Syntax:       
~~~~~
GetComment dfname entry
~~~~~ 

Gets a value of a Comment attribute at *entry* label. 

**Example:** 
~~~~~
GetComment D 0:2
~~~~~ 

@subsubsection occt_draw_5_5_11  SetExtStringArray

Syntax:       
~~~~~
SetExtStringArray dfname entry lower upper value1 value2 …
~~~~~ 

Finds or creates an *ExtStringArray* attribute at *entry* label with lower and upper bounds and sets *value1*, *value2*… 

**Example:** 
~~~~~
SetExtStringArray D 0:2 1 3 *string1* *string2* *string3*
~~~~~ 

@subsubsection occt_draw_5_5_12  GetExtStringArray

Syntax:       
~~~~~
GetExtStringArray dfname entry
~~~~~ 

Gets a value of an ExtStringArray attribute at *entry* label. 

**Example:** 
~~~~~
GetExtStringArray D 0:2 
~~~~~

@subsubsection occt_draw_5_5_13  SetName

Syntax:       
~~~~~
SetName dfname entry value 
~~~~~

Finds or creates a Name attribute at *entry* label and sets *value*. 

**Example:** 
~~~~~
SetName D 0:2 *My name* 
~~~~~

@subsubsection occt_draw_5_5_14  GetName

Syntax:       
~~~~~
GetName dfname entry 
~~~~~

Gets a value of a Name attribute at *entry* label. 

**Example:** 
~~~~~
GetName D 0:2 
~~~~~

@subsubsection occt_draw_5_5_15  SetReference

Syntax:       
~~~~~
SetReference dfname entry reference 
~~~~~

Creates a Reference attribute at *entry* label and sets *reference*. 

**Example:** 
~~~~~
SetReference D 0:2 0:4 
~~~~~

@subsubsection occt_draw_5_5_16  GetReference

Syntax:       
~~~~~
GetReference dfname entry 
~~~~~

Gets a value of a Reference attribute at *entry* label. 

**Example:** 
~~~~~
GetReference D 0:2 
~~~~~

@subsubsection occt_draw_5_5_17  SetUAttribute

Syntax:       
~~~~~
SetUAttribute dfname entry localGUID 
~~~~~

Creates a UAttribute attribute at *entry* label with *localGUID*. 

**Example:** 
~~~~~
set localGUID "c73bd076-22ee-11d2-acde-080009dc4422" 
SetUAttribute D 0:2 ${localGUID} 
~~~~~

@subsubsection occt_draw_5_5_18  GetUAttribute

Syntax:       
~~~~~
GetUAttribute dfname entry loacalGUID 
~~~~~

Finds a *UAttribute* at *entry* label with *localGUID*. 

**Example:** 
~~~~~
set localGUID "c73bd076-22ee-11d2-acde-080009dc4422" 
GetUAttribute D 0:2 ${localGUID} 
~~~~~

@subsubsection occt_draw_5_5_19  SetFunction

Syntax:       
~~~~~
SetFunction dfname entry ID failure 
~~~~~

Finds or creates a *Function* attribute at *entry* label with driver ID and *failure* index. 

**Example:** 
~~~~~
set ID "c73bd076-22ee-11d2-acde-080009dc4422" 
SetFunction D 0:2 ${ID} 1 
~~~~~

@subsubsection occt_draw_5_5_20  GetFunction

Syntax:       
~~~~~
GetFunction dfname entry ID failure 
~~~~~

Finds a Function attribute at *entry* label and sets driver ID to *ID* variable and failure index to *failure* variable. 

**Example:** 
~~~~~
GetFunction D 0:2 ID failure 
~~~~~

@subsubsection occt_draw_5_5_21  NewShape

Syntax:       
~~~~~
NewShape dfname entry [shape] 
~~~~~

Finds or creates a Shape attribute at *entry* label. Creates or updates the associated *NamedShape* attribute by *shape* if *shape* is defined. 

**Example:** 
~~~~~
box b 10 10 10 
NewShape D 0:2 b 
~~~~~

@subsubsection occt_draw_5_5_22  SetShape

Syntax:       
~~~~~
SetShape dfname entry shape 
~~~~~

Creates or updates a *NamedShape* attribute at *entry* label by *shape*. 

**Example:** 
~~~~~
box b 10 10 10 
SetShape D 0:2 b 
~~~~~

@subsubsection occt_draw_5_5_23  GetShape

Syntax:       
~~~~~
GetShape2 dfname entry shape 
~~~~~

Sets a shape from NamedShape attribute associated with *entry* label to *shape* draw variable. 

**Example:** 
~~~~~
GetShape2 D 0:2 b 
~~~~~

@subsection occt_draw_5_6  Geometric attributes commands


@subsubsection occt_draw_5_6_1  SetPoint

Syntax:       
~~~~~
SetPoint dfname entry point
~~~~~ 

Finds or creates a Point attribute at *entry* label and sets *point* as generated in the associated *NamedShape* attribute. 

**Example:** 
~~~~~
point p 10 10 10 
SetPoint D 0:2 p 
~~~~~

@subsubsection occt_draw_5_6_2  GetPoint

Syntax:       
~~~~~
GetPoint dfname entry [drawname] 
~~~~~

Gets a vertex from *NamedShape* attribute at *entry* label and sets it to *drawname* variable, if it is defined. 

**Example:** 
~~~~~
GetPoint D 0:2 p 
~~~~~

@subsubsection occt_draw_5_6_3  SetAxis

Syntax:       
~~~~~
SetAxis dfname entry axis 
~~~~~

Finds or creates an Axis attribute at *entry* label and sets *axis* as generated in the associated *NamedShape* attribute. 

**Example:** 
~~~~~
line l 10 20 30 100 200 300 
SetAxis D 0:2 l 
~~~~~

@subsubsection occt_draw_5_6_4  GetAxis

Syntax:       
~~~~~
GetAxis dfname entry [drawname] 
~~~~~

Gets a line from *NamedShape* attribute at *entry* label and sets it to *drawname* variable, if it is defined. 

**Example:** 
~~~~~
GetAxis D 0:2 l 
~~~~~

@subsubsection occt_draw_5_6_5  SetPlane

Syntax:       
~~~~~
SetPlane dfname entry plane 
~~~~~

Finds or creates a Plane attribute at *entry* label and sets *plane* as generated in the associated *NamedShape* attribute. 

**Example:** 
~~~~~
plane pl 10 20 30 –1 0 0 
SetPlane D 0:2 pl 
~~~~~

@subsubsection occt_draw_5_6_6  GetPlane

Syntax:       
~~~~~
GetPlane dfname entry [drawname] 
~~~~~

Gets a plane from *NamedShape* attribute at *entry* label and sets it to *drawname* variable, if it is defined. 

**Example:** 
~~~~~
GetPlane D 0:2 pl 
~~~~~

@subsubsection occt_draw_5_6_7  SetGeometry

Syntax:       
~~~~~
SetGeometry dfname entry [type] [shape] 
~~~~~

Creates a Geometry attribute at *entry* label and sets *type* and *shape* as generated in the associated *NamedShape* attribute if they are defined. *type* must be one of the following: *any, pnt, lin, cir, ell, spl, pln, cyl*. 

**Example:** 
~~~~~
point p 10 10 10 
SetGeometry D 0:2 pnt p 
~~~~~

@subsubsection occt_draw_5_6_8  GetGeometryType

Syntax:       
~~~~~
GetGeometryType dfname entry
~~~~~ 

Gets a geometry type from Geometry attribute at *entry* label. 

**Example:** 
~~~~~
GetGeometryType D 0:2 
~~~~~

@subsubsection occt_draw_5_6_9  SetConstraint

Syntax:       
~~~~~
SetConstraint dfname entry keyword geometrie [geometrie …] 
SetConstraint dfname entry "plane" geometrie 
SetConstraint dfname entry "value" value
~~~~~  

1. Creates a Constraint attribute at *entry* label and sets *keyword* constraint between geometry(ies). 
*keyword* must be one of the following: 
*rad, dia, minr, majr, tan, par, perp, concentric, equal, dist, angle, eqrad, symm, midp, eqdist, fix, rigid,* or *from, axis, mate, alignf, aligna, axesa, facesa, round, offset* 
2. Sets plane for the existing constraint. 
3. Sets value for the existing constraint. 

**Example:** 
~~~~~
SetConstraint D 0:2 "value" 5 
~~~~~

@subsubsection occt_draw_5_6_10  GetConstraint

Syntax:       
~~~~~
GetConstraint dfname entry
~~~~~ 

Dumps a Constraint attribute at *entry* label 

**Example:** 
~~~~~
GetConstraint D 0:2 
~~~~~

@subsubsection occt_draw_5_6_11  SetVariable

Syntax:       
~~~~~
SetVariable dfname entry isconstant(0/1) units 
~~~~~

Creates a Variable attribute at *entry* label and sets *isconstant* flag and *units* as a string. 

**Example:** 
~~~~~
SetVariable D 0:2 1 "mm" 
~~~~~

@subsubsection occt_draw_5_6_12  GetVariable

Syntax:       
~~~~~
GetVariable dfname entry isconstant units 
~~~~~

Gets an *isconstant* flag and units of a Variable attribute at *entry* label. 

**Example:** 
~~~~~
GetVariable D 0:2 isconstant units 
puts "IsConstant=${isconstant}" 
puts "Units=${units}" 
~~~~~

@subsection occt_draw_5_7  Tree attributes commands


@subsubsection occt_draw_5_7_1  RootNode

Syntax:       
~~~~~
RootNode dfname treenodeentry [ID]
~~~~~ 

Returns the ultimate father of *TreeNode* attribute identified by its *treenodeentry* and its *ID* (or default ID, if *ID* is not defined). 


@subsubsection occt_draw_5_7_2  SetNode

Syntax:       
~~~~~
SetNode dfname treenodeentry [ID]
~~~~~ 

Creates a *TreeNode* attribute on the *treenodeentry* label with its tree *ID* (or assigns a default ID, if the *ID* is not defined). 


@subsubsection occt_draw_5_7_3  AppendNode

Syntax:       
~~~~~
AppendNode dfname fatherentry childentry [fatherID]
~~~~~ 


Inserts a *TreeNode* attribute with its tree *fatherID* (or default ID, if *fatherID* is not defined) on *childentry* as last child of *fatherentry*. 




@subsubsection occt_draw_5_7_4  PrependNode

Syntax:       
~~~~~
PrependNode dfname fatherentry childentry [fatherID]
~~~~~ 


Inserts a *TreeNode* attribute with its tree *fatherID* (or default ID, if *fatherID* is not defined) on *childentry* as first child of *fatherentry*. 


@subsubsection occt_draw_5_7_5  InsertNodeBefore

Syntax:       
~~~~~
InsertNodeBefore dfname treenodeentry beforetreenode [ID]
~~~~~ 

Inserts a *TreeNode* attribute with tree *ID* (or default ID, if *ID* is not defined) *beforetreenode* before *treenodeentry*. 


@subsubsection occt_draw_5_7_6  InsertNodeAfter

Syntax:       
~~~~~
InsertNodeAfter dfname treenodeentry aftertreenode [ID]
~~~~~ 

Inserts a *TreeNode* attribute with tree *ID* (or default ID, if *ID* is not defined) *aftertreenode* after *treenodeentry*. 


@subsubsection occt_draw_5_7_7  DetachNode

Syntax:       
~~~~~
DetachNode dfname treenodeentry [ID]
~~~~~ 

Removes a *TreeNode* attribute with tree *ID* (or default ID, if *ID* is not defined) from *treenodeentry*. 


@subsubsection occt_draw_5_7_8  ChildNodeIterate

Syntax:       
~~~~~
ChildNodeIterate dfname treenodeentry alllevels(0/1) [ID]
~~~~~ 


Iterates on the tree of *TreeNode* attributes with tree *ID* (or default ID, if *ID* is not defined). If *alllevels* is set to *1* it explores not only the first, but all the sub Step levels.
 
**Example:** 
~~~~~
Label D 0:2 
Label D 0:3 
Label D 0:4 
Label D 0:5 
Label D 0:6 
Label D 0:7 
Label D 0:8 
Label D 0:9 

# Set root node 
SetNode D 0:2 

AppendNode D 0:2 0:4 
AppendNode D 0:2 0:5 
PrependNode D 0:4 0:3 
PrependNode D 0:4 0:8 
PrependNode D 0:4 0:9 

InsertNodeBefore D 0:5 0:6 
InsertNodeAfter D 0:4 0:7 

DetachNode D 0:8 


# List all levels 
ChildNodeIterate D 0:2 1 

==0:4 
==0:9 
==0:3 
==0:7 
==0:6 
==0:5 


# List only first levels 
ChildNodeIterate D 0:2 1 

==0:4 
==0:7 
==0:6 
==0:5 
~~~~~

@subsubsection occt_draw_5_7_9  InitChildNodeIterator

Syntax:       
~~~~~
InitChildNodeIterator dfname treenodeentry alllevels(0/1) [ID]
~~~~~ 


Initializes the iteration on the tree of *TreeNode* attributes with tree *ID* (or default ID, if *ID* is not defined). If *alllevels* is set to *1* it explores not only the first, but also all sub Step levels. 

**Example:** 
~~~~~
InitChildNodeIterate D 0:5 1 
set aChildNumber 0 
for {set i 1} {$i  100} {incr i} { 
    if {[ChildNodeMore] == *TRUE*} { 
        puts *Tree node = [ChildNodeValue]* 
        incr aChildNumber 
        ChildNodeNext 
    } 
} 
puts "aChildNumber=$aChildNumber"
~~~~~ 

@subsubsection occt_draw_5_7_10  ChildNodeMore

Syntax:       
~~~~~
ChildNodeMore
~~~~~ 

Returns TRUE if there is a current item in the iteration. 


@subsubsection occt_draw_5_7_11  ChildNodeNext

Syntax:       
~~~~~
ChildNodeNext
~~~~~ 

Moves to the next Item. 


@subsubsection occt_draw_5_7_12  ChildNodeValue

Syntax:       
~~~~~
ChildNodeValue
~~~~~ 

Returns the current treenode of *ChildNodeIterator*. 


@subsubsection occt_draw_5_7_13  ChildNodeNextBrother

Syntax:       
~~~~~
ChildNodeNextBrother
~~~~~ 

Moves to the next *Brother*. If there is none, goes up. This method is interesting only with *allLevels* behavior. 


@subsection occt_draw_5_8   Standard presentation commands


@subsubsection occt_draw_5_8_1  AISInitViewer

Syntax:       
~~~~~
AISInitViewer docname
~~~~~ 

Creates and sets *AISViewer* attribute at root label, creates AIS viewer window. 

**Example:** 
~~~~~
AISInitViewer D 
~~~~~

@subsubsection occt_draw_5_8_2  AISRepaint

Syntax:       
~~~~~
AISRepaint docname 
~~~~~

Updates the AIS viewer window. 

**Example:** 
~~~~~
AISRepaint D 
~~~~~

@subsubsection occt_draw_5_8_3  AISDisplay

Syntax:       
~~~~~
AISDisplay docname entry [not_update] 
~~~~~

Displays a presantation of *AISobject* from *entry* label in AIS viewer. If *not_update* is not defined then *AISobject* is recomputed and all visualization settings are applied. 

**Example:** 
~~~~~
AISDisplay D 0:5 
~~~~~

@subsubsection occt_draw_5_8_4  AISUpdate

Syntax:       
~~~~~
AISUpdate docname entry 
~~~~~

Recomputes a presentation of *AISobject* from *entry* label and applies the visualization setting in AIS viewer. 

**Example:** 
~~~~~
AISUpdate D 0:5 
~~~~~

@subsubsection occt_draw_5_8_5  AISErase

Syntax:       
~~~~~
AISErase docname entry 
~~~~~

Erases *AISobject* of *entry* label in AIS viewer. 

**Example:** 
~~~~~
AISErase D 0:5 
~~~~~

@subsubsection occt_draw_5_8_6  AISRemove

Syntax:       
~~~~~
AISRemove docname entry 
~~~~~

Erases *AISobject* of *entry* label in AIS viewer, then *AISobject* is removed from *AIS_InteractiveContext*. 

**Example:** 
~~~~~
AISRemove D 0:5 
~~~~~

@subsubsection occt_draw_5_8_7  AISSet

Syntax:       
~~~~~
AISSet docname entry ID 
~~~~~

Creates *AISPresentation* attribute at *entry* label and sets as driver ID. ID must be one of the following: *A* (*axis*), *C* (*constraint*), *NS* (*namedshape*), *G* (*geometry*), *PL* (*plane*), *PT* (*point*). 

**Example:** 
~~~~~
AISSet D 0:5 NS 
~~~~~

@subsubsection occt_draw_5_8_8  AISDriver

Syntax:       
~~~~~
AISDriver docname entry [ID] 
~~~~~

Returns DriverGUID stored in *AISPresentation* attribute of an *entry* label or sets a new one. ID must be one of the following: *A* (*axis*), *C* (*constraint*), *NS* (*namedshape*), *G* (*geometry*), *PL* (*plane*), *PT* (*point*). 

**Example:** 
~~~~~
# Get Driver GUID 
AISDriver D 0:5 
~~~~~

@subsubsection occt_draw_5_8_9  AISUnset

Syntax:       
~~~~~
AISUnset docname entry 
~~~~~

Deletes *AISPresentation* attribute (if it exists) of an *entry* label. 

**Example:** 
~~~~~
AISUnset D 0:5 
~~~~~

@subsubsection occt_draw_5_8_10  AISTransparency

Syntax:       
~~~~~
AISTransparency docname entry [transparency] 
~~~~~

Sets (if *transparency* is defined) or gets the value of transparency for *AISPresentation* attribute of an *entry* label. 

**Example:** 
~~~~~
AISTransparency D 0:5 0.5 
~~~~~

@subsubsection occt_draw_5_8_11  AISHasOwnTransparency

Syntax:       
~~~~~
AISHasOwnTransparency docname entry 
~~~~~

Tests *AISPresentation* attribute of an *entry* label by own transparency. 

**Example:** 
~~~~~
AISHasOwnTransparency D 0:5 
~~~~~

@subsubsection occt_draw_5_8_12  AISMaterial

Syntax:       
~~~~~
AISMaterial docname entry [material] 
~~~~~

Sets (if *material* is defined) or gets the value of transparency for *AISPresentation* attribute of an *entry* label. *material* is integer from 0 to 20 (see <a href="#occt_draw_4_5_6">meshmat</a> command). 

**Example:** 
~~~~~
AISMaterial D 0:5 5 
~~~~~

@subsubsection occt_draw_5_8_13  AISHasOwnMaterial

Syntax:       
~~~~~
AISHasOwnMaterial docname entry 
~~~~~

Tests *AISPresentation* attribute of an *entry* label by own material. 

**Example:** 
~~~~~
AISHasOwnMaterial D 0:5 
~~~~~

@subsubsection occt_draw_5_8_14  AISColor

Syntax:       
~~~~~
AISColor docname entry [color] 
~~~~~

Sets (if *color* is defined) or gets value of color for *AISPresentation* attribute of an *entry* label. *color* is integer from 0 to 516 (see color names in *vsetcolor*). 

**Example:** 
~~~~~
AISColor D 0:5 25 
~~~~~

@subsubsection occt_draw_5_8_15  AISHasOwnColor

Syntax:       
~~~~~
AISHasOwnColor docname entry 
~~~~~

Tests *AISPresentation* attribute of an *entry* label by own color. 

**Example:** 
~~~~~
AISHasOwnColor D 0:5 
~~~~~

@section occt_draw_6 Geometry commands

@subsection occt_draw_6_1 Overview

Draw provides a set of commands to test geometry libraries. These commands are found in the TGEOMETRY executable, or in any Draw executable which includes *GeometryTest* commands. 

In the context of Geometry, Draw includes the following types of variable: 

  * 2d and 3d points
  * The 2d curve, which corresponds to *Curve* in *Geom2d*.
  * The 3d curve and surface, which correspond to *Curve* and *Surface* in <a href="user_guides__modeling_data.html#occt_modat_1">Geom package</a>.
  
Draw geometric variables never share data; the *copy* command will always make a complete copy of the content of the variable. 

The following topics are covered in the nine sections of this chapter: 

  * **Curve creation** deals with the various types of curves and how to create them.
  * **Surface creation** deals with the different types of surfaces and how to create them.
  * **Curve and surface modification** deals with the commands used to modify the definition of curves and surfaces, most of which concern modifications to bezier and bspline curves.
  * **Geometric transformations** covers translation, rotation, mirror image and point scaling transformations.
  * **Curve and Surface Analysis** deals with the commands used to compute points, derivatives and curvatures.
  * **Intersections** presents intersections of surfaces and curves.
  * **Approximations** deals with creating curves and surfaces from a set of points.
  * **Constraints** concerns construction of 2d circles and lines by constraints such as tangency.
  * **Display** describes commands to control the display of curves and surfaces.

Where possible, the commands have been made broad in application, i.e. they apply to 2d curves, 3d curves and surfaces. For instance, the *circle* command may create a 2d or a 3d circle depending on the number of arguments given. 

Likewise, the *translate* command will process points, curves or surfaces, depending on argument type. You may not always find the specific command you are looking for in the section where you expect it to be. In that case, look in another section. The *trim* command, for example, is described in the surface section. It can, nonetheless, be used with curves as well. 

@subsection occt_draw_6_2  Curve creation

This section deals with both points and curves. Types of curves are: 

  * Analytical curves such as lines, circles, ellipses, parabolas, and hyperbolas.
  * Polar curves such as bezier curves and bspline curves.
  * Trimmed curves and offset curves made from other curves with the *trim* and *offset* commands. Because they are used on both curves and surfaces, the *trim* and *offset* commands are described in the *surface creation* section.
  * NURBS can be created from other curves using *convert* in the *Surface Creation* section.
  * Curves can be created from the isoparametric lines of surfaces by the *uiso* and *viso* commands.
  * 3d curves can be created from 2d curves and vice versa using the *to3d* and *to2d* commands. The *project* command computes a 2d curve on a 3d surface.

Curves are displayed with an arrow showing the last parameter. 


@subsubsection occt_draw_6_2_1 point

Syntax:      
~~~~~
point name x y [z] 
~~~~~
  
Creates a 2d or 3d point, depending on the number of arguments. 

**Example:**
~~~~~
# 2d point 
point p1 1 2 

# 3d point 
point p2 10 20 -5 
~~~~~
  
@subsubsection occt_draw_6_2_2  line

Syntax:      
~~~~~
line name x y [z] dx dy [dz]
~~~~~ 

  
Creates a 2d or 3d line. *x y z* are the coordinates of the line’s point of origin; *dx, dy, dz* give the direction vector. 

A 2d line will be represented as *x y dx dy*, and a 3d line as *x y z dx dy dz* . A line is parameterized along its length starting from the point of origin along the direction vector. The direction vector is normalized and must not be null. Lines are infinite, even though their representation is not. 

**Example:** 
~~~~~
# a 2d line at 45 degrees of the X axis 
line l 2 0 1 1 

# a 3d line through the point 10 0 0 and parallel to Z 
line l 10 0 0 0 0 1 
~~~~~

@subsubsection occt_draw_6_2_3  circle

Syntax:      
~~~~~
circle name x y [z [dx dy dz]] [ux uy [uz]] radius
~~~~~ 

Creates a 2d or a 3d circle. 

In 2d, *x, y* are the coordinates of the center and *ux, uy* define the vector towards the point of origin of the parameters. By default, this direction is (1,0). The X Axis of the local coordinate system defines the origin of the parameters of the circle. Use another vector than the x axis to change the origin of parameters. 

In 3d, *x, y, z* are the coordinates of the center; *dx, dy, dz* give the vector normal to the plane of the circle. By default, this vector is (0,0,1) i.e. the Z axis (it must not be null). *ux, uy, uz* is the direction of the origin; if not given, a default direction will be computed. This vector must neither be null nor parallel to *dx, dy, dz*. 

The circle is parameterized by the angle in [0,2*pi] starting from the origin and. Note that the specification of origin direction and plane is the same for all analytical curves and surfaces. 

**Example:** 
~~~~~
# A 2d circle of radius 5 centered at 10,-2 
circle c1 10 -2 5 

# another 2d circle with a user defined origin 
# the point of parameter 0 on this circle will be 
# 1+sqrt(2),1+sqrt(2) 
circle c2 1 1 1 1 2 

# a 3d circle, center 10 20 -5, axis Z, radius 17 
circle c3 10 20 -5 17 

# same 3d circle with axis Y 
circle c4 10 20 -5 0 1 0 17 

# full 3d circle, axis X, origin on Z 
circle c5 10 20 -5 1 0 0 0 0 1 17 
~~~~~

@subsubsection occt_draw_6_2_4  ellipse

Syntax: 
~~~~~
ellipse name x y [z [dx dy dz]] [ux uy [uz]] firstradius secondradius 
~~~~~

Creates a 2d or 3d ellipse. In a 2d ellipse, the first two arguments define the center; in a 3d ellipse, the first three. The axis system is given by *firstradius*, the major radius, and *secondradius*, the minor radius. The parameter range of the ellipse is [0,2.*pi] starting from the X axis and going towards the Y axis. The Draw ellipse is parameterized by an angle: 

~~~~~
P(u) = O + firstradius*cos(u)*Xdir + secondradius*sin(u)*Ydir 
~~~~~
where: 

  * P is the point of parameter *u*,
  * *O, Xdir* and *Ydir* are respectively the origin, *X Direction* and *Y Direction* of its local coordinate system.
 
**Example:**
~~~~~
# default 2d ellipse 
ellipse e1 10 5 20 10 

# 2d ellipse at angle 60 degree 
ellipse e2 0 0 1 2 30 5 

# 3d ellipse, in the XY plane 
ellipse e3 0 0 0 25 5 

# 3d ellipse in the X,Z plane with axis 1, 0 ,1 
ellipse e4 0 0 0 0 1 0 1 0 1 25 5 
~~~~~

@subsubsection occt_draw_6_2_5  hyperbola

Syntax:      
~~~~~
hyperbola name x y [z [dx dy dz]] [ux uy [uz]] firstradius secondradius
~~~~~ 

Creates a 2d or 3d conic. The first arguments define the center. The axis system is given by *firstradius*, the major radius, and *secondradius*, the minor radius. Note that the hyperbola has only one branch, that in the X direction. 

The Draw hyperbola is parameterized as follows: 
~~~~~
P(U) = O + firstradius*Cosh(U)*XDir + secondradius*Sinh(U)*YDir 
~~~~~
where: 

  * *P* is the point of parameter *U*,
  * *O, XDir* and *YDir* are respectively the origin, *X Direction* and *YDirection* of its local coordinate system. 

**Example:** 
~~~~~
# default 2d hyperbola, with asymptotes 1,1 -1,1 
hyperbola h1 0 0 30 30 

# 2d hyperbola at angle 60 degrees 
hyperbola h2 0 0 1 2 20 20 

# 3d hyperbola, in the XY plane 
hyperbola h3 0 0 0 50 50 
~~~~~

@subsubsection occt_draw_6_2_6  parabola

Syntax:      
~~~~~
parabola name x y [z [dx dy dz]] [ux uy [uz]] FocalLength 
~~~~~

Creates a 2d or 3d parabola. in the axis system defined by the first arguments. The origin is the apex of the parabola. 

The *Geom_Parabola* is parameterized as follows: 

~~~~~
P(u) = O + u*u/(4.*F)*XDir + u*YDir 
~~~~~

where: 
  * *P* is the point of parameter *u*,
  * *O, XDir* and *YDir* are respectively the origin, *X Direction* and *Y Direction* of its local coordinate system,
  * *F* is the focal length of the parabola.

**Example:** 
~~~~~
# 2d parabola 
parabola p1 0 0 50 

# 2d parabola with convexity +Y 
parabola p2 0 0 0 1 50 

# 3d parabola in the Y-Z plane, convexity +Z 
parabola p3 0 0 0 1 0 0 0 0 1 50 
~~~~~

@subsubsection occt_draw_6_2_7  beziercurve, 2dbeziercurve

Syntax:      
~~~~~
beziercurve name nbpole pole, [weight] 
2dbeziercurve name nbpole pole, [weight]
~~~~~ 

Creates a 3d rational or non-rational Bezier curve. Give the number of poles (control points,) and the coordinates of the poles *(x1 y1 z1 [w1] x2 y2 z2 [w2])*. The degree will be *nbpoles-1*. To create a rational curve, give weights with the poles. You must give weights for all poles or for none. If the weights of all the poles are equal, the curve is polynomial, and therefore non-rational. 

**Example:** 
~~~~~
# a rational 2d bezier curve (arc of circle) 
2dbeziercurve ci 3 0 0 1 10 0 sqrt(2.)/2. 10 10 1 

# a 3d bezier curve, not rational 
beziercurve cc 4 0 0 0 10 0 0 10 0 10 10 10 10 
~~~~~

@subsubsection occt_draw_6_2_8  bsplinecurve, 2dbsplinecurve, pbsplinecurve, 2dpbsplinecurve

Syntax:      
~~~~~
bsplinecurve   name degree nbknots knot, umult pole, weight
2dbsplinecurve name degree nbknots knot, umult pole, weight

pbsplinecurve   name degree nbknots knot, umult pole, weight (periodic)
2dpbsplinecurve name degree nbknots knot, umult pole, weight (periodic)
~~~~~

Creates 2d or 3d bspline curves; the **pbsplinecurve** and **2dpbsplinecurve** commands create periodic bspline curves. 

A bspline curve is defined by its degree, its periodic or non-periodic nature, a table of knots and a table of poles (i.e. control points). Consequently, specify the degree, the number of knots, and for each knot, the multiplicity, for each pole, the weight. In the syntax above, the commas link the adjacent arguments which they fall between: knot and multiplicities, pole and weight. 

The table of knots is an increasing sequence of reals without repetition. 
Multiplicities must be lower or equal to the degree of the curve. For non-periodic curves, the first and last multiplicities can be equal to degree+1. For a periodic curve, the first and last multiplicities must be equal. 

The poles must be given with their weights, use weights of 1 for a non rational curve, the number of poles must be: 

  * For a non periodic curve: Sum of multiplicities - degree + 1
  * For a periodic curve: Sum of multiplicities - last multiplicity

**Example:** 
~~~~~
# a bspline curve with 4 poles and 3 knots 
bsplinecurve bc 2 3 0 3 1 1 2 3 \ 
10 0 7 1 7 0 7 1 3 0 8 1 0 0 7 1 
# a 2d periodic circle (parameter from 0 to 2*pi !!) 
dset h sqrt(3)/2 
2dpbsplinecurve c 2 \ 
4 0 2 pi/1.5 2 pi/0.75 2 2*pi 2 \ 
0 -h/3 1 \ 
0.5 -h/3 0.5 \ 
0.25 h/6 1 \ 
0 2*h/3 0.5 \ 
-0.25 h/6 1 \ 
-0.5 -h/3 0.5 \ 
0 -h/3 1 
~~~~~

**Note** that you can create the **NURBS** subset of bspline curves and surfaces by trimming analytical curves and surfaces and executing the command *convert*. 


@subsubsection occt_draw_6_2_9  uiso, viso

Syntax:      
~~~~~
uiso name surface u 
viso name surface u 
~~~~~

Creates a U or V isoparametric curve from a surface. 

**Example:** 
~~~~~
# create a cylinder and extract iso curves 

cylinder c 10 
uiso c1 c pi/6 
viso c2 c 
~~~~~

**Note** that this cannot be done from offset surfaces.


@subsubsection occt_draw_6_2_10  to3d, to2d

Syntax:      
~~~~~
to3d name curve2d [plane] 
to2d name curve3d [plane] 
~~~~~

Create respectively a 3d curve from a 2d curve and a 2d curve from a 3d curve. The transformation uses a planar surface to define the XY plane in 3d (by default this plane is the default OXYplane). **to3d** always gives a correct result, but as **to2d** is not a projection, it may surprise you. It is always correct if the curve is planar and parallel to the plane of projection. The points defining the curve are projected on the plane. A circle, however, will remain a circle and will not be changed to an ellipse. 

**Example:** 
~~~~~
# the following commands 
circle c 0 0 5 
plane p -2 1 0 1 2 3 
to3d c c p 

# will create the same circle as 
circle c -2 1 0 1 2 3 5 
~~~~~

See also: **project** 


@subsubsection occt_draw_6_2_11  project

Syntax:      
~~~~~
project name curve3d surface 
~~~~~

Computes a 2d curve in the parametric space of a surface corresponding to a 3d curve. This can only be used on analytical surfaces. 

If we, for example, intersect a cylinder and a plane and project the resulting ellipse on the cylinder, this will create a 2d sinusoid-like bspline. 

~~~~~
cylinder c 5 
plane p 0 0 0 0 1 1 
intersect i c p 
project i2d i c 
~~~~~

@subsection occt_draw_6_3  Surface creation

The following types of surfaces exist: 
  * Analytical surfaces: plane, cylinder, cone, sphere, torus;
  * Polar surfaces: bezier surfaces, bspline surfaces;
  * Trimmed and Offset surfaces;
  * Surfaces produced by Revolution and Extrusion, created from curves with the *revsurf* and *extsurf*;
  * NURBS surfaces.

Surfaces are displayed with isoparametric lines. To show the parameterization, a small parametric line with a length 1/10 of V is displayed at 1/10 of U. 

@subsubsection occt_draw_6_3_1  plane

Syntax:      
~~~~~
plane name [x y z [dx dy dz [ux uy uz]]]
~~~~~ 

Creates an infinite plane. 

A plane is the same as a 3d coordinate system, *x,y,z* is the origin, *dx, dy, dz* is the Z direction and *ux, uy, uz* is the X direction. 

The plane is perpendicular to Z and X is the U parameter. *dx,dy,dz* and *ux,uy,uz* must not be null or collinear. *ux,uy,uz* will be modified to be orthogonal to *dx,dy,dz*. 

There are default values for the coordinate system. If no arguments are given, the global system (0,0,0), (0,0,1), (1,0,0). If only the origin is given, the axes are those given by default(0,0,1), (1,0,0). If the origin and the Z axis are given, the X axis is generated perpendicular to the Z axis. 

Note that this definition will be used for all analytical surfaces. 

**Example:** 
~~~~~
# a plane through the point 10,0,0 perpendicular to X 
# with U direction on Y 
plane p1 10 0 0 1 0 0 0 1 0 

# an horixontal plane with origin 10, -20, -5 
plane p2 10 -20 -5 
~~~~~

@subsubsection occt_draw_6_3_2  cylinder

Syntax:      
~~~~~
cylinder name [x y z [dx dy dz [ux uy uz]]] radius 
~~~~~

A cylinder is defined by a coordinate system, and a radius. The surface generated is an infinite cylinder with the Z axis as the axis. The U parameter is the angle starting from X going in the Y direction. 

**Example:** 
~~~~~
# a cylinder on the default Z axis, radius 10 
cylinder c1 10 

# a cylinder, also along the Z axis but with origin 5, 
10, -3 
cylinder c2 5 10 -3 10 

# a cylinder through the origin and on a diagonal 
# with longitude pi/3 and latitude pi/4 (euler angles) 
dset lo pi/3. la pi/4. 
cylinder c3 0 0 0 cos(la)*cos(lo) cos(la)*sin(lo) 
sin(la) 10 
~~~~~

@subsubsection occt_draw_6_3_3  cone

Syntax:      
~~~~~
cone name [x y z [dx dy dz [ux uy uz]]] semi-angle radius 
~~~~~
Creates a cone in the infinite coordinate system along the Z-axis. The radius is that of the circle at the intersection of the cone and the XY plane. The semi-angle is the angle formed by the cone relative to the axis; it should be between –90 and 90. If the radius is 0, the vertex is the origin. 

**Example:** 
~~~~~
# a cone at 45 degrees at the origin on Z 
cone c1 45 0 

# a cone on axis Z with radius r1 at z1 and r2 at z2 
cone c2 0 0 z1 180.*atan2(r2-r1,z2-z1)/pi r1 
~~~~~

@subsubsection occt_draw_6_3_4  sphere

Syntax:      
~~~~~
sphere name [x y z [dx dy dz [ux uy uz]]] radius 
~~~~~

Creates a sphere in the local coordinate system defined in the **plane** command. The sphere is centered at the origin. 

To parameterize the sphere, *u* is the angle from X to Y, between 0 and 2*pi. *v* is the angle in the half-circle at angle *u* in the plane containing the Z axis. *v* is between -pi/2 and pi/2. The poles are the points Z = +/- radius; their parameters are u,+/-pi/2 for any u in 0,2*pi. 

**Example:**
~~~~~ 
# a sphere at the origin 
sphere s1 10 
# a sphere at 10 10 10, with poles on the axis 1,1,1 
sphere s2 10 10 10 1 1 1 10 
~~~~~

@subsubsection occt_draw_6_3_5  torus

Syntax:      
~~~~~
torus name [x y z [dx dy dz [ux uy uz]]] major minor
~~~~~ 

Creates a torus in the local coordinate system with the given major and minor radii. *Z* is the axis for the major radius. The major radius may be lower in value than the minor radius. 

To parameterize a torus, *u* is the angle from X to Y; *v* is the angle in the plane at angle *u* from the XY plane to Z. *u* and *v* are in 0,2*pi. 

**Example:** 
~~~~~
# a torus at the origin 
torus t1 20 5 

# a torus in another coordinate system 
torus t2 10 5 -2 2 1 0 20 5 
~~~~~


@subsubsection occt_draw_6_3_6  beziersurf

Syntax:      
~~~~~
beziersurf name nbupoles nbvolpes pole, [weight] 
~~~~~

Use this command to create a bezier surface, rational or non-rational. First give the numbers of poles in the u and v directions. 

Then give the poles in the following order: *pole(1, 1), pole(nbupoles, 1), pole(1, nbvpoles)* and *pole(nbupoles, nbvpoles)*. 

Weights may be omitted, but if you give one weight you must give all of them. 

**Example:** 
~~~~~
# a non-rational degree 2,3 surface 
beziersurf s 3 4 \ 
0 0 0 10 0 5 20 0 0 \ 
0 10 2 10 10 3 20 10 2 \ 
0 20 10 10 20 20 20 20 10 \ 
0 30 0 10 30 0 20 30 0 
~~~~~

@subsubsection occt_draw_6_3_7   bsplinesurf, upbsplinesurf, vpbsplinesurf, uvpbsplinesurf

Syntax:     
~~~~~
bsplinesurf name udegree nbuknots uknot umult ... nbvknot vknot 
vmult ... x y z w ... 
upbsplinesurf ... 
vpbsplinesurf ... 
uvpbsplinesurf ... 
~~~~~

* **bsplinesurf** generates bspline surfaces;
* **upbsplinesurf** creates a bspline surface periodic in u; 
* **vpbsplinesurf** creates one periodic in v; 
* **uvpbsplinesurf** creates one periodic in uv. 

The syntax is similar to the *bsplinecurve* command. First give the degree in u and the knots in u with their multiplicities, then do the same in v. The poles follow. The number of poles is the product of the number in u and the number in v. 

See *bsplinecurve* to compute the number of poles, the poles are first given in U as in the *beziersurf* command. You must give weights if the surface is rational. 

**Example:** 
~~~~~
# create a bspline surface of degree 1 2 
# with two knots in U and three in V 
bsplinesurf s \ 
1 2 0 2 1 2 \ 
2 3 0 3 1 1 2 3 \ 
0 0 0 1 10 0 5 1 \ 
0 10 2 1 10 10 3 1 \ 
0 20 10 1 10 20 20 1 \ 
0 30 0 1 10 30 0 1 
~~~~~


@subsubsection occt_draw_6_3_8  trim, trimu, trimv

Syntax:      
~~~~~
trim newname name [u1 u2 [v1 v2]] 
trimu newname name 
trimv newname name 
~~~~~

The **trim** commands create trimmed curves or trimmed surfaces. Note that trimmed curves and surfaces are classes of the *Geom* package. 
* *trim* creates either a new trimmed curve from a curve or a new trimmed surface in u and v from a surface.
* *trimu* creates a u-trimmed surface, 
* *trimv* creates a v-trimmed surface. 

After an initial trim, a second execution with no parameters given recreates the basis curve. The curves can be either 2d or 3d. If the trimming parameters decrease and if the curve or surface is not periodic, the direction is reversed. 

**Note** that a trimmed curve or surface contains a copy of the basis geometry: modifying that will not modify the trimmed geometry. Trimming trimmed geometry will not create multiple levels of trimming. The basis geometry will be used. 

**Example:** 
~~~~~
# create a 3d circle 
circle c 0 0 0 10 

# trim it, use the same variable, the original is 
deleted 
trim c c 0 pi/2 

# the original can be recovered! 
trim orc c 

# trim again 
trim c c pi/4 pi/2 

# the original is not the trimmed curve but the basis 
trim orc c 

# as the circle is periodic, the two following commands 
are identical 
trim cc c pi/2 0 
trim cc c pi/2 2*pi 

# trim an infinite cylinder 
cylinder cy 10 
trimv cy cy 0 50 
~~~~~

@subsubsection occt_draw_6_3_9  offset

Syntax:      
~~~~~
offset name basename distance [dx dy dz]
~~~~~ 

Creates offset curves or surfaces at a given distance from a basis curve or surface. Offset curves and surfaces are classes from the *Geom *package. 

The curve can be a 2d or a 3d curve. To compute the offsets for a 3d curve, you must also give a vector *dx,dy,dz*. For a planar curve, this vector is usually the normal to the plane containing the curve. 

The offset curve or surface copies the basic geometry, which can be modified later. 

**Example:** 
~~~~~
# graphic demonstration that the outline of a torus 
# is the offset of an ellipse 
smallview +X+Y 
dset angle pi/6 
torus t 0 0 0 0 cos(angle) sin(angle) 50 20 
fit 
ellipse e 0 0 0 50 50*sin(angle) 
# note that the distance can be negative 
offset l1 e 20 0 0 1 
~~~~~

@subsubsection occt_draw_6_3_10  revsurf

Syntax:      
~~~~~
revsurf name curvename x y z dx dy dz
~~~~~ 

Creates a surface of revolution from a 3d curve. 

A surface of revolution or revolved surface is obtained by rotating a curve (called the *meridian*) through a complete revolution about an axis (referred to as the *axis of revolution*). The curve and the axis must be in the same plane (the *reference plane* of the surface). Give the point of origin x,y,z and the vector dx,dy,dz to define the axis of revolution. 

To parameterize a surface of revolution: u is the angle of rotation around the axis. Its origin is given by the position of the meridian on the surface. v is the parameter of the meridian. 

**Example:** 
~~~~~
# another way of creating a torus like surface 
circle c 50 0 0 20 
revsurf s c 0 0 0 0 1 0 
~~~~~

@subsubsection occt_draw_6_3*11  extsurf

Syntax:      
~~~~~
extsurf newname curvename dx dy dz 
~~~~~

Creates a surface of linear extrusion from a 3d curve. The basis curve is swept in a given direction,the *direction of extrusion* defined by a vector. 

In the syntax, *dx,dy,dz* gives the direction of extrusion. 

To parameterize a surface of extrusion: *u* is the parameter along the extruded curve; the *v* parameter is along the direction of extrusion. 

**Example:** 
~~~~~
# an elliptic cylinder 
ellipse e 0 0 0 10 5 
extsurf s e 0 0 1 
# to make it finite 
trimv s s 0 10 
~~~~~

@subsubsection occt_draw_6_3_12  convert

Syntax:      
~~~~~
convert newname name 
~~~~~

Creates a 2d or 3d NURBS curve or a NURBS surface from any 2d curve, 3d curve or surface. In other words, conics, beziers and bsplines are turned into NURBS. Offsets are not processed.
 
**Example:** 
~~~~~
# turn a 2d arc of a circle into a 2d NURBS 
circle c 0 0 5 
trim c c 0 pi/3 
convert c1 c 

# an easy way to make a planar bspline surface 
plane p 
trim p p -1 1 -1 1 
convert p1 p 
~~~~~

**Note** that offset curves and surfaces are not processed by this command.

@subsection occt_draw_6_4  Curve and surface modifications

Draw provides commands to modify curves and surfaces, some of them are general, others restricted to bezier curves or bsplines. 

General modifications: 

  * Reversing the parametrization: **reverse**, **ureverse**, **vreverse**

Modifications for both bezier curves and bsplines: 

  * Exchanging U and V on a surface: **exchuv**
  * Segmentation: **segment**, **segsur**
  * Increasing the degree: **incdeg**, **incudeg**, **incvdeg**
  * Moving poles: **cmovep**, **movep**, **movecolp**, **moverowp**

Modifications for bezier curves: 

  * Adding and removing poles: **insertpole**, **rempole**, **remcolpole**, **remrowpole**

Modifications for bspline: 

  * Inserting and removing knots: **insertknot**, **remknot**, **insertuknot**, **remuknot**, **insetvknot**, **remvknot**
  * Modifying periodic curves and surfaces: **setperiodic**, **setnotperiodic**, **setorigin**, **setuperiodic**, **setunotperiodic**, **setuorigin**, **setvperiodic**, **setvnotperiodic**, **setvorigin**



@subsubsection occt_draw_6_4_1  reverse, ureverse, vreverse


Syntax:            
~~~~~
reverse curvename 
ureverse surfacename 
vreverse surfacename 
~~~~~

The **reverse** command reverses the parameterization and inverses the orientation of a 2d or 3d curve. Note that the geometry is modified. To keep the curve or the surface, you must copy it before modification. 

**ureverse** or **vreverse** reverse the u or v parameter of a surface. Note that the new parameters of the curve may change according to the type of curve. For instance, they will change sign on a line or stay 0,1 on a bezier. 

Reversing a parameter on an analytical surface may create an indirect coordinate system. 

**Example:** 
~~~~~
# reverse a trimmed 2d circle 
circle c 0 0 5 
trim c c pi/4 pi/2 
reverse c 

# dumping c will show that it is now trimmed between 
# 3*pi/2 and 7*pi/4 i.e. 2*pi-pi/2 and 2*pi-pi/4 
~~~~~

@subsubsection occt_draw_6_4_2  exchuv

Syntax:                 
~~~~~
exchuv surfacename 
~~~~~

For a bezier or bspline surface this command exchanges the u and v parameters. 

**Example:** 
~~~~~
# exchanging u and v on a spline (made from a cylinder) 
cylinder c 5 
trimv c c 0 10 
convert c1 c 
exchuv c1 
~~~~~

@subsubsection occt_draw_6_4_3  segment, segsur

Syntax:                  
~~~~~
segment curve Ufirst Ulast 
segsur surface Ufirst Ulast Vfirst Vlast 
~~~~~

**segment** and **segsur** segment a bezier curve and a bspline curve or surface respectively. 

These commands modify the curve to restrict it between the new parameters: *Ufirst*, the starting point of the modified curve, and *Ulast*, the end point. *Ufirst* is less than *Ulast*. 

This command must not be confused with **trim** which creates a new geometry. 

**Example:** 
~~~~~
# segment a bezier curve in half 
beziercurve c 3 0 0 0 10 0 0 10 10 0 
segment c ufirst ulast 
~~~~~

@subsubsection occt_draw_6_4_4  iincudeg, incvdeg

Syntax:      
~~~~~
incudeg surfacename newdegree 
incvdeg surfacename newdegree 
~~~~~

**incudeg** and **incvdeg** increase the degree in the U or V parameter of a bezier or bspline surface.
 
**Example:** 
~~~~~
# make a planar bspline and increase the degree to 2 3 
plane p 
trim p p -1 1 -1 1 
convert p1 p 
incudeg p1 2 
incvdeg p1 3 
~~~~~

**Note** that the geometry is modified.


@subsubsection occt_draw_6_4_5  cmovep, movep, movecolp, moverowp

Syntax:      
~~~~~
cmovep curve index dx dy [dz] 
movep surface uindex vindex dx dy dz 
movecolp surface uindex dx dy dz 
moverowp surface vindex dx dy dz 
~~~~~

**move** methods translate poles of a bezier curve, a bspline curve or a bspline surface. 
* **cmovep** and **movep** translate one pole with a given index. 
* **movecolp** and **moverowp** translate a whole column (expressed by the *uindex*) or row (expressed by the *vindex*) of poles. 

**Example:** 
~~~~~
# start with a plane 
# transform to bspline, raise degree and add relief 
plane p 
trim p p -10 10 -10 10 
convert p1 p 
incud p1 2 
incvd p1 2 
movecolp p1 2 0 0 5 
moverowp p1 2 0 0 5 
movep p1 2 2 0 0 5 
~~~~~

@subsubsection occt_draw_6_4_6  insertpole, rempole, remcolpole, remrowpole

Syntax:                  
~~~~~
insertpole curvename index x y [z] [weight] 
rempole curvename index 
remcolpole surfacename index 
remrowpole surfacename index
~~~~~ 

**insertpole** inserts a new pole into a 2d or 3d bezier curve. You may add a weight for the pole. The default value for the weight is 1. The pole is added at the position after that of the index pole. Use an index 0 to insert the new pole before the first one already existing in your drawing. 

**rempole** removes a pole from a 2d or 3d bezier curve. Leave at least two poles in the curves. 

**remcolpole** and **remrowpole** remove a column or a row of poles from a bezier surface. A column is in the v direction and a row in the u direction The resulting degree must be at least 1; i.e there will be two rows and two columns left. 

**Example:** 
~~~~~
# start with a segment, insert a pole at end 
# then remove the central pole 
beziercurve c 2 0 0 0 10 0 0 
insertpole c 2 10 10 0 
rempole c 2 
~~~~~

@subsubsection occt_draw_6_4_7  insertknot, insertuknot, insertvknot

Syntax:                  
~~~~~
insertknot name knot [mult = 1] [knot mult ...] 
insertuknot surfacename knot mult 
insertvknot surfacename knot mult 
~~~~~

**insertknot** inserts knots in the knot sequence of a bspline curve. You must give a knot value and a target multiplicity. The default multiplicity is 1. If there is already a knot with the given value and a multiplicity lower than the target one, its multiplicity will be raised. 

**insertuknot** and **insertvknot** insert knots in a surface. 

**Example:** 
~~~~~
# create a cylindrical surface and insert a knot 
cylinder c 10 
trim c c 0 pi/2 0 10 
convert c1 c 
insertuknot c1 pi/4 1 
~~~~~

@subsubsection occt_draw_6_4_8  remknot, remuknot, remvknot

Syntax:      
~~~~~
remknot index [mult] [tol] 
remuknot index [mult] [tol] 
remvknot index [mult] [tol] 
~~~~~

**remknot** removes a knot from the knot sequence of a curve or a surface. Give the index of the knot and optionally, the target multiplicity. If the target multiplicity is not 0, the multiplicity of the knot will be lowered. As the curve may be modified, you are allowed to set a tolerance to control the process. If the tolerance is low, the knot will only be removed if the curve will not be modified. 

By default, if no tolerance is given, the knot will always be removed. 

**Example:** 
~~~~~
# bspline circle, remove a knot 
circle c 0 0 5 
convert c1 c 
incd c1 5 
remknot c1 2 
~~~~~

**Note** that Curves or Surfaces may be modified.


@subsubsection occt_draw_6_4_9  setperiodic, setnotperiodic, setuperiodic, setunotperiodic, setvperiodic, setvnotperiodic

Syntax:      
~~~~~
setperiodic curve 
setnotperiodic curve 
setuperiodic surface 
setunotperiodic surface 
setvperiodic surface 
setvnotperiodic surface
~~~~~ 

**setperiodic** turns a bspline curve into a periodic bspline curve; the knot vector stays the same and excess poles are truncated. The curve may be modified if it has not been closed. **setnotperiodic** removes the periodicity of a periodic curve. The pole table mau be modified. Note that knots are added at the beginning and the end of the knot vector and the multiplicities are knots set to degree+1 at the start and the end. 

**setuperiodic** and **setvperiodic** make the u or the v parameter of bspline surfaces periodic; **setunotperiodic**, and **setvnotperiodic** remove periodicity from the u or the v parameter of bspline surfaces. 

**Example:** 
~~~~~
# a circle deperiodicized 
circle c 0 0 5 
convert c1 c 
setnotperiodic c1 
~~~~~

@subsubsection occt_draw_6_4_10  setorigin, setuorigin, setvorigin

Syntax:      
~~~~~
setorigin curvename index 
setuorigin surfacename index 
setuorigin surfacename index 
~~~~~

These commands change the origin of the parameters on periodic curves or surfaces. The new origin must be an existing knot. To set an origin other than an existing knot, you must first insert one with the *insertknot* command. 

**Example:** 
~~~~~
# a torus with new U and V origins 
torus t 20 5 
convert t1 t 
setuorigin t1 2 
setvorigin t1 2
~~~~~ 


@subsection occt_draw_6_5  Transformations

Draw provides commands to apply linear transformations to geometric objects: they include translation, rotation, mirroring and scaling. 

@subsubsection occt_draw_6_5_1  translate, dtranslate

Syntax:                  
~~~~~
translate name [names ...] dx dy dz 
2dtranslate name [names ...] dx dy 
~~~~~

The **Translate** command translates 3d points, curves and surfaces along a vector *dx,dy,dz*. You can translate more than one object with the same command. 

For 2d points or curves, use the **2dtranslate** command. 

**Example:** 
~~~~~
# 3d tranlation 
point p 10 20 30 
circle c 10 20 30 5 
torus t 10 20 30 5 2 
translate p c t 0 0 15
~~~~~
 
*NOTE* 
*Objects are modified by this command.* 

@subsubsection occt_draw_6_5_2  rotate, 2drotate

Syntax:      
~~~~~
rotate name [name ...] x y z dx dy dz angle 
2drotate name [name ...] x y angle
~~~~~ 

The **rotate** command rotates a 3d point curve or surface. You must give an axis of rotation with a point *x,y,z*, a vector *dx,dy,dz* and an angle in degrees. 

For a 2d rotation, you need only give the center point and the angle. In 2d or 3d, the angle can be negative. 

**Example:** 
~~~~~
# make a helix of circles. create a scripte file with 
this code and execute it using **source**. 
circle c0 10 0 0 3 
for {set i 1} {$i = 10} {incr i} { 
copy c[expr $i-1] c$i 
translate c$i 0 0 3 
rotate c$i 0 0 0 0 0 1 36 
} 
~~~~~

@subsubsection occt_draw_6_5_3  pmirror, lmirror, smirror, dpmirror, dlmirror

Syntax:      
~~~~~
pmirror name [names ...] x y z 
lmirror name [names ...] x y z dx dy dz 
smirror name [names ...] x y z dx dy dz 
2dpmirror name [names ...] x y 
2dlmirror name [names ...] x y dx dy 
~~~~~

The mirror commands perform a mirror transformation of 2d or 3d geometry. 

* **pmirror** is the point mirror, mirroring 3d curves and surfaces about a point of symmetry. 
* **lmirror** is the line mirror commamd, mirroring 3d curves and surfaces about an axis of symmetry.
* **smirror** is the surface mirror, mirroring 3d curves and surfaces about a plane of symmetry. In the last case, the plane of symmetry is perpendicular to dx,dy,dz. 
* **2dpmirror** is the point mirror in 2D.
* **2dlmirror** is the axis symmetry mirror in 2D.

**Example:** 
~~~~~
# build 3 images of a torus 
torus t 10 10 10 1 2 3 5 1 
copy t t1 
pmirror t1 0 0 0 
copy t t2 
lmirror t2 0 0 0 1 0 0 
copy t t3 
smirror t3 0 0 0 1 0 0 
~~~~~

@subsubsection occt_draw_6_5_4  pscale, dpscale

Syntax:                  
~~~~~
pscale name [name ...] x y z s 
2dpscale name [name ...] x y s 
~~~~~

The **pscale** and **2dpscale** commands transform an object by point scaling. You must give the center and the scaling factor. Because other scalings modify the type of the object, they are not provided. For example, a sphere may be transformed into an ellipsoid. Using a scaling factor of -1 is similar to using **pmirror**.

 
**Example:** 
~~~~~
# double the size of a sphere 
sphere s 0 0 0 10 
pscale s 0 0 0 2 
~~~~~

@subsection occt_draw_6_6  Curve and surface analysis

**Draw** provides methods to compute information about curves and surfaces: 

  * **coord** to find the coordinates of a point.
  * **cvalue** and **2dcvalue** to compute points and derivatives on curves.
  * **svalue** to compute points and derivatives on a surface.
  * **localprop** and **minmaxcurandif** to compute the curvature on a curve.
  * **parameters** to compute (u,v) values for a point on a surface.
  * **proj** and **2dproj** to project a point on a curve or a surface.
  * **surface_radius** to compute the curvature on a surface.

@subsubsection occt_draw_6_6_1  coord

Syntax:            
~~~~~
coord P x y [z] 
~~~~~

Sets the x, y (and optionally z) coordinates of the point P. 

**Example:** 
~~~~~
# translate a point 
point p 10 5 5 
translate p 5 0 0 
coord p x y z 
# x value is 15 
~~~~~


@subsubsection occt_draw_6_6_2   cvalue, 2dcvalue

Syntax:      
~~~~~
cvalue curve U x y z [d1x d1y d1z [d2x d2y d2z]] 
2dcvalue curve U x y [d1x d1y [d2x d2y]] 
~~~~~

For a curve at a given parameter, and depending on the number of arguments, **cvalue** computes the coordinates in *x,y,z*, the first derivative in *d1x,d1y,d1z* and the second derivative in *d2x,d2y,d2z*. 

**Example:**

Let on a bezier curve at parameter 0 the point is the first pole; the first derivative is the vector to the second pole multiplied by the degree; the second derivative is the difference first to the second pole, second to the third pole multipied by *degree-1* : 

~~~~~
2dbeziercurve c 4 0 0 1 1 2 1 3 0 
2dcvalue c 0 x y d1x d1y d2x d2y 

# values of x y d1x d1y d2x d2y 
# are 0 0 3 3 0 -6 
~~~~~

@subsubsection occt_draw_6_6_3  svalue

Syntax: 
~~~~~
svalue surfname U v x y z [dux duy duz dvx dvy dvz [d2ux d2uy d2uz d2vx d2vy d2vz d2uvx d2uvy d2uvz]] 
~~~~~

Computes points and derivatives on a surface for a pair of parameter values. The result depends on the number of arguments. You can compute the first and the second derivatives. 

**Example:** 
~~~~~
# display points on a sphere 
sphere s 10 
for {dset t 0} {[dval t] = 1} {dset t t+0.01} { 
svalue s t*2*pi t*pi-pi/2 x y z 
point . x y z 
} 
~~~~~

@subsubsection occt_draw_6_6_4  localprop, minmaxcurandinf

Syntax:      
~~~~~
localprop curvename U 
minmaxcurandinf curve
~~~~~ 

**localprop** computes the curvature of a curve. 
**minmaxcurandinf** computes and prints the parameters of the points where the curvature is minimum and maximum on a 2d curve. 

**Example:** 
~~~~~
# show curvature at the center of a bezier curve 
beziercurve c 3 0 0 0 10 2 0 20 0 0 
localprop c 0.5 
== Curvature : 0.02 
~~~~~

@subsubsection occt_draw_6_6_5  parameters

Syntax:      
~~~~~
parameters surf/curve x y z U [V] 
~~~~~

Returns the parameters on the surface of the 3d point *x,y,z* in variables *u* and *v*. This command may only be used on analytical surfaces: plane, cylinder, cone, sphere and torus. 

**Example:** 
~~~~~
# Compute parameters on a plane 
plane p 0 0 10 1 1 0 
parameters p 5 5 5 u v 
# the values of u and v are : 0 5 
~~~~~

@subsubsection occt_draw_6_6_6  proj, dproj

Syntax:      
~~~~~
proj name x y z 
2dproj name xy 
~~~~~

Use **proj** to project a point on a 3d curve or a surface and **2dproj** for a 2d curve. 

The command will compute and display all points in the projection. The lines joining the point to the projections are created with the names *ext_1, ext_2, ... *

**Example:** 

Let us project a point on a torus 

~~~~~
torus t 20 5 
proj t 30 10 7 
== ext_1 ext_2 ext_3 ext_4 
~~~~~

@subsubsection occt_draw_6_6_7  surface_radius

Syntax:      
~~~~~
surface_radius surface u v [c1 c2] 
~~~~~

Computes the main curvatures of a surface at parameters *(u,v)*. If there are extra arguments, their curvatures are stored in variables *c1* and *c2*. 

**Example:** 

Let us compute curvatures of a cylinder:

~~~~~
cylinder c 5 
surface_radius c pi 3 c1 c2 
== Min Radius of Curvature : -5 
== Min Radius of Curvature : infinite 
~~~~~


@subsection occt_draw_6_7  Intersections

* **intersect** computes intersections of surfaces; 
* **2dintersect** computes intersections of 2d curves.

@subsubsection occt_draw_6_7_1  intersect

Syntax:      
~~~~~
intersect name surface1 surface2
~~~~~ 

Intersects two surfaces; if there is one intersection curve it will be named *name*, if there are more than one they will be named *name_1*, *name_2*, ... 

**Example:** 
~~~~~
# create an ellipse 
cone c 45 0 
plane p 0 0 40 0 1 5 
intersect e c p 
~~~~~

@subsubsection occt_draw_6_7_2  dintersect

Syntax:      
~~~~~
2dintersect curve1 curve2 
~~~~~

Displays the intersection points between two 2d curves. 

**Example:** 
~~~~~
# intersect two 2d ellipses 
ellipse e1 0 0 5 2 
ellipse e2 0 0 0 1 5 2 
2dintersect e1 e2 
~~~~~

@subsection occt_draw_6_8  Approximations

Draw provides command to create curves and surfaces by approximation. 

* **2dapprox** fits a curve through 2d points; 
* **appro** fits a curve through 3d points;
* **surfapp** and **grilapp** fit a surface through 3d points;
* **2dinterpolate** interpolates a curve. 

@subsubsection occt_draw_6_8_1   appro, dapprox

Syntax:      
~~~~~
appro result nbpoint [curve] 
2dapprox result nbpoint [curve / x1 y1 x2 y2]
~~~~~ 

These commands fit a curve through a set of points. First give the number of points, then choose one of the three ways available to get the points. If you have no arguments, click on the points. If you have a curve argument or a list of points, the command launches computation of the points on the curve. 

**Example:** 

Let us pick points and they will be fitted 

~~~~~
2dapprox c 10 
~~~~~

@subsubsection occt_draw_6_8_2  surfapp, grilapp


Syntax: 
~~~~~
surfapp name nbupoints nbvpoints x y z .... 
grilapp name nbupoints nbvpoints xo dx yo dy z11 z12 ... 
~~~~~

* **surfapp** fits a surface through an array of u and v points, nbupoints*nbvpoints. 
* **grilapp** has the same function, but the x,y coordinates of the points are on a grid starting at x0,y0 with steps dx,dy. 

**Example:** 
~~~~~
# a surface using the same data as in the beziersurf 
example sect 4.4 
surfapp s 3 4 \ 
0 0 0 10 0 5 20 0 0 \ 
0 10 2 10 10 3 20 10 2 \ 
0 20 10 10 20 20 20 20 10 \ 
0 30 0 10 30 0 20 30 0 
~~~~~

@subsection occt_draw_6_9  Constraints

* **cirtang** constructs 2d circles tangent to curves;
* **lintan** constructs 2d lines tangent to curves. 


@subsubsection occt_draw_6_9_1  cirtang

Syntax: 
~~~~~
cirtang cname curve/point/radius curve/point/radius curve/point/radius 
~~~~~

Builds all circles satisfying the three constraints which are either a curve (the circle must be tangent to that curve), a point (the circle must pass through that point), or a radius for the circle. Only one constraint can be a radius. The solutions will be stored in variables *name_1*, *name_2*, etc. 

**Example:** 
~~~~~
# a point, a line and a radius. 2 solutions 
point p 0 0 
line 1 10 0 -1 1 
cirtang c p 1 4 
== c_1 c_2 
~~~~~

@subsubsection occt_draw_6_9_2  lintan

Syntax:      
~~~~~
lintan name curve curve [angle] 
~~~~~

Builds all 2d lines tangent to two curves. If the third angle argument is given the second curve must be a line and **lintan** will build all lines tangent to the first curve and forming the given angle with the line. The angle is given in degrees. The solutions are named *name_1*, *name_2*, etc. 

**Example:** 
~~~~~
# lines tangent to 2 circles, 4 solutions 
circle c1 -10 0 10 
circle c2 10 0 5 
lintan l c1 c2 

# lines at 15 degrees tangent to a circle and a line, 2 
solutions: l1_1 l1_2 
circle c1 -10 0 1 
line l 2 0 1 1 
lintan l1 c1 l 15 
~~~~~

@subsection occt_draw_6_10  Display

Draw provides commands to control the display of geometric objects. Some display parameters are used for all objects, others are valid for surfaces only, some for bezier and bspline only, and others for bspline only. 

On curves and surfaces, you can control the mode of representation with the **dmode** command. You can control the parameters for the mode with the **defle** command and the **discr** command, which control deflection and discretization respectively. 

On surfaces, you can control the number of isoparametric curves displayed on the surface with the **nbiso** command. 

On bezier and bspline curve and surface you can toggle the display of the control points with the **clpoles** and **shpoles** commands. 

On bspline curves and surfaces you can toggle the display of the knots with the **shknots** and **clknots** commands. 


@subsubsection occt_draw_6_10_1  dmod, discr, defle

Syntax:      
~~~~~
dmode name [name ...] u/d 
discr name [name ...] nbintervals 
defle name [name ...] deflection 
~~~~~

**dmod** command allows choosing the display mode for a curve or a surface. 

In mode *u*, or *uniform deflection*, the points are computed to keep the polygon at a distance lower than the deflection of the geometry. The deflection is set with the *defle* command. This mode involves intensive use of computational power. 

In *d*, or discretization mode, a fixed number of points is computed. This number is set with the *discr* command. This is the default mode. On a bspline, the fixed number of points is computed for each span of the curve. (A span is the interval between two knots). 

If the curve or the isolines seem to present too many angles, you can either increase the discretization or lower the deflection, depending on the mode. This will increase the number of points. 

**Example:** 
~~~~~
# increment the number of points on a big circle 
circle c 0 0 50 50 
discr 100 

# change the mode 
dmode c u 
~~~~~

@subsubsection occt_draw_6_10_2   nbiso

Syntax:      
~~~~~
nbiso name [names...] nuiso nviso 
~~~~~

Changes the number of isoparametric curves displayed on a surface in the U and V directions. On a bspline surface, isoparametric curves are displayed by default at knot values. Use *nbiso* to turn this feature off. 

**Example:** 

Let us  display 35 meridians and 15 parallels on a sphere:
~~~~~ 
sphere s 20 
nbiso s 35 15 
~~~~~

@subsubsection occt_draw_6_10_3  clpoles, shpoles

Syntax:      
~~~~~
clpoles name 
shpoles name 
~~~~~

On bezier and bspline curves and surfaces, the control polygon is displayed by default: *clpoles* erases it and *shpoles* restores it. 

**Example:** 

Let us make a bezier curve and erase the poles 

~~~~~
beziercurve c 3 0 0 0 10 0 0 10 10 0 
clpoles c 
~~~~~

@subsubsection occt_draw_6_10_4  clknots, shknots

Syntax:   
~~~~~
clknots name 
shknots name 
~~~~~

By default, knots on a bspline curve or surface are displayed with markers at the points with parametric value equal to the knots. *clknots* removes them and *shknots* restores them. 

**Example:** 
~~~~~
# hide the knots on a bspline curve 
bsplinecurve bc 2 3 0 3 1 1 2 3 \ 
10 0 7 1 7 0 7 1 3 0 8 1 0 0 7 1 
clknots bc
~~~~~


@section occt_draw_7 Topology commands

Draw provides a set of commands to test OCCT Topology libraries. The Draw commands are found in the DRAWEXE executable or in any executable including the BRepTest commands. 

Topology defines the relationship between simple geometric entities, which can thus be linked together to represent complex shapes. The type of variable used by Topology in Draw is the shape variable. 

The <a href="user_guides__modeling_data.html#occt_modat_5">different topological shapes</a> include: 

  * **COMPOUND**: A group of any type of topological object.
  * **COMPSOLID**: A set of solids connected by their faces. This expands the notions of WIRE and SHELL to solids.
  * **SOLID**: A part of space limited by shells. It is three dimensional.
  * **SHELL**: A set of faces connected by their edges. A shell can be open or closed.
  * **FACE**: In 2d, a plane; in 3d, part of a surface. Its geometry is constrained (trimmed) by contours. It is two dimensional.
  * **WIRE**: A set of edges connected by their vertices. It can be open or closed depending on whether the edges are linked or not.
  * **EDGE**: A topological element corresponding to a restrained curve. An edge is generally limited by vertices. It has one dimension.
  * **VERTEX**: A topological element corresponding to a point. It has a zero dimension.

Shapes are usually shared. **copy** will create a new shape which shares its representation with the original. Nonetheless, two shapes sharing the same topology can be moved independently (see the section on **transformation**). 

The following topics are covered in the eight sections of this chapter: 

  * Basic shape commands to handle the structure of shapes and control the display.
  * Curve and surface topology, or methods to create topology from geometry and vice versa.
  * Primitive construction commands: box, cylinder, wedge etc.
  * Sweeping of shapes.
  * Transformations of shapes: translation, copy, etc.
  * Topological operations, or booleans.
  * Drafting and blending.
  * Analysis of shapes.


@subsection occt_draw_7_1  Basic topology

The set of basic commands allows simple operations on shapes, or step-by-step construction of objects. These commands are useful for analysis of shape structure and include: 

  * **isos** and **discretisation** to control display of shape faces by isoparametric curves .
  * **orientation**, **complement** and **invert** to modify topological attributes such as orientation.
  * **explode**, **exwire** and **nbshapes** to analyze the structure of a shape.
  * **emptycopy**, **add**, **compound** to create shapes by stepwise construction.

In Draw, shapes are displayed using isoparametric curves. There is color coding for the edges: 

  * a red edge is an isolated edge, which belongs to no faces.
  * a green edge is a free boundary edge, which belongs to one face,
  * a yellow edge is a shared edge, which belongs to at least two faces.


@subsubsection occt_draw_7_1_1  isos, discretisation

Syntax:                  
~~~~~
isos [name ...][nbisos] 
discretisation nbpoints
~~~~~
 
Determines or changes the number of isoparametric curves on shapes. 

The same number is used for the u and v directions. With no arguments, *isos* prints the current default value. To determine, the number of isos for a shape, give it name as the first argument. 

*discretisation* changes the default number of points used to display the curves. The default value is 30. 

**Example:** 
~~~~~
# Display only the edges (the wireframe) 
isos 0 
~~~~~

**Warning**: don’t confuse *isos* and *discretisation* with the geometric commands *nbisos* and *discr*. 


@subsubsection occt_draw_7_1_2  orientation, complement, invert, normals, range

Syntax:      
~~~~~
orientation name [name ...] F/R/E/I 
complement name [name ...] 
invert name 
normals s (length = 10), disp normals 
range name value value 
~~~~~

* **orientation** assigns the orientation of shapes - simple and complex - to one of the following four values: *FORWARD, REVERSED, INTERNAL, EXTERNAL*. 
* **complement** changes the current orientation of shapes to its complement, *FORWARD - REVERSED, INTERNAL - EXTERNAL*. 
* **invert** creates a new shape which is a copy of the original with the orientation all subshapes reversed. For example, it may be useful to reverse the normals of a solid. 
* *normals** returns the assignment of colors to orientation values. 
* **range** defines the length of a selected edge by defining the values of a starting point and an end point.
 
**Example:** 
~~~~~
# to invert normals of a box 
box b 10 20 30 
normals b 5 
invert b 
normals b 5 

# to assign a value to an edge 
box b1 10 20 30 
# to define the box as edges 
explode b1 e 
b_1 b_2 b_3 b_4 b_5 b_6 b_7 b_8 b_9 b_10 b_11 b_12 
# to define as an edge 
makedge e 1 
# to define the length of the edge as starting from 0 
and finishing at 1 
range e 0 1 
~~~~~

@subsubsection occt_draw_7_1_3  explode, exwire, nbshapes

Syntax:      
~~~~~
explode name [C/So/Sh/F/W/E/V] 
exwire name 
nbshapes name 
~~~~~

**explode** extracts subshapes from an entity. The subshapes will be named *name_1*, *name_2*, ... Note that they are not copied but shared with the original. 

With name only, **explode** will extract the first sublevel of shapes: the shells of a solid or the edges of a wire, for example. With one argument, **explode** will extract all subshapes of that type: *C* for compounds, *So* for solids, *Sh* for shells, *F* for faces, *W* for wires, *E* for edges, *V* for vertices. 

**exwire** is a special case of **explode** for wires, which extracts the edges in an ordered way, if possible. Each edge, for example, is connected to the following one by a vertex. 

**nbshapes** counts the number of shapes of each type in an entity. 

**Example:** 
~~~~~
# on a box 
box b 10 20 30 

# whatis returns the type and various information 
whatis b 
= b is a shape SOLID FORWARD Free Modified 

# make one shell 
explode b 
whatis b_1 
= b_1 is a shape SHELL FORWARD Modified Orientable 
Closed 

# extract the edges b_1, ... , b_12 
explode b e 
==b_1 ... b_12 

# count subshapes 
nbshapes b 
== 
Number of shapes in b 
VERTEX : 8 
EDGE : 12 
WIRE : 6 
FACE : 6 
SHELL : 1 
SOLID : 1 
COMPSOLID : 0 
COMPOUND : 0 
SHAPE : 34 
~~~~~

@subsubsection occt_draw_7_1_4  emptycopy, add, compound

Syntax:                  
~~~~~
emptycopy [newname] name 
add name toname 
compound [name ...] compoundname 
~~~~~

**emptycopy** returns an empty shape with the same orientation, location, and geometry as the target shape, but with no sub-shapes. If the newname argument is not given, the new shape is stored with the same name. This command is used to modify a frozen shape. A frozen shape is a shape used by another one. To modify it, you must emptycopy it. Its subshape may be reinserted with the **add** command. 

**add** inserts shape *C* into shape *S*. Verify that *C* and *S* reference compatible types of objects: 
  * Any *Shape* can be added to a *Compound*.
  * Only a *Solid* can be added to a *CompSolid*.
  * Only a *Shell* can *Edge* or a *Vertex* can be added into a *Solid*.
  * Only a *Face* can be added to a *Shell*.
  * Only a *Wire* and *Vertex* can be added in a *Solid*.
  * Only an *Edge* can be added to a *Wire*.
  * Only a *Vertex* can be added to an *Edge*.
  * Nothing can be added to a *Vertex*.

**emptycopy** and **add** should be used with care. 

On the other hand, **compound** is a safe way to achieve a similar result. It creates a compound from shapes. If no shapes are given, the compound is empty. 

**Example:** 
~~~~~
# a compound with three boxes 
box b1 0 0 0 1 1 1 
box b2 3 0 0 1 1 1 
box b3 6 0 0 1 1 1 
compound b1 b2 b3 c 
~~~~~

@subsubsection occt_draw_7_1_5  checkshape

Syntax:                  
~~~~~
checkshape [-top] shape [result] [-short] 
~~~~~

Where: 
* *top* – optional parameter, which allows checking only topological validity of a shape. 
* *shape*– the only required parameter which represents the name of the shape to check. 
* *result* – optional parameter which is the prefix of the output shape names. 
* *short* – a short description of the check. 

**checkshape** examines the selected object for topological and geometric coherence. The object should be a three dimensional shape. 

**Example:** 
~~~~~
# checkshape returns a comment valid or invalid 
box b1 0 0 0 1 1 1 
checkshape b1 
# returns the comment 
this shape seems to be valid 
~~~~~

**Note** that this test is performed using the tolerance set in the algorithm.


@subsection occt_draw_7_2  Curve and surface topology

This group of commands is used to create topology from shapes and to extract shapes from geometry. 

  * To create vertices, use the **vertex** command.
  * To create edges use, the **edge**, **mkedge** commands.
  * To create wires, use the **wire**, **polyline**, **polyvertex** commands.
  * To create faces, use the **mkplane**, **mkface** commands.
  * To extract the geometry from edges or faces, use the **mkcurve** and **mkface** commands.
  * To extract the 2d curves from edges or faces, use the **pcurve** command.


@subsubsection occt_draw_7_2_1  vertex

Syntax:      
~~~~~
vertex name [x y z / p edge] 
~~~~~

Creates a vertex at either a 3d location x,y,z or the point at parameter p on an edge. 

**Example:** 
~~~~~
vertex v1 10 20 30 
~~~~~

@subsubsection occt_draw_7_2_2  edge, mkedge, uisoedge, visoedge

Syntax:      
~~~~~
edge name vertex1 vertex2 
mkedge edge curve [surface] [pfirst plast] [vfirst [pfirst] vlast [plast]] 
uisoedge edge face u v1 v2 
visoedge edge face v u1 u2 
~~~~~

* **edge** creates a straight line edge between two vertices. 
* **mkedge** generates edges from curves<.Two parameters can be given for the vertices: the first and last parameters of the curve are given by default. Vertices can also be given with their parameters, this option allows blocking the creation of new vertices. If the parameters of the vertices are not given, they are computed by projection on the curve. Instead of a 3d curve, a 2d curve and a surface can be given. 

**Example:** 
~~~~~
# straight line edge 
vertex v1 10 0 0 
vertex v2 10 10 0 
edge e1 v1 v2 

# make a circular edge 
circle c 0 0 0 5 
mkedge e2 c 0 pi/2 

# A similar result may be achieved by trimming the curve 
# The trimming is removed by mkedge 
trim c c 0 pi/2 
mkedge e2 c 
~~~~~

* **visoedge** and **uisoedge** are commands that generate a *uiso* parameter edge or a *viso* parameter edge. 

**Example:** 
~~~~~
# to create an edge between v1 and v2 at point u 
# to create the example plane 
plane p 
trim p p 0 1 0 1 
convert p p 
incudeg p 3 
incvdeg p 3 
movep p 2 2 0 0 1 
movep p 3 3 0 0 0.5 
mkface p p 
# to create the edge in the plane at the u axis point 
0.5, and between the v axis points v=0.2 and v =0.8 
uisoedge e p 0.5 0.20 0.8 
~~~~~

@subsubsection occt_draw_7_2_3  wire, polyline, polyvertex

Syntax:      
~~~~~
wire wirename e1/w1 [e2/w2 ...] 
polyline name x1 y1 z1 x2 y2 z2 ... 
polyvertex name v1 v2 ... 
~~~~~

**wire** creates a wire from edges or wires. The order of the elements should ensure that the wire is connected, and vertex locations will be compared to detect connection. If the vertices are different, new edges will be created to ensure topological connectivity. The original edge may be copied in the new one. 

**polyline** creates a polygonal wire from point coordinates. To make a closed wire, you should give the first point again at the end of the argument list. 

**polyvertex** creates a polygonal wire from vertices. 

**Example:** 
~~~~~
# create two polygonal wires 
# glue them and define as a single wire 
polyline w1 0 0 0 10 0 0 10 10 0 
polyline w2 10 10 0 0 10 0 0 0 0 
wire w w1 w2 
~~~~~

@subsubsection occt_draw_7_2_4  profile

Syntax       
~~~~~
profile name [code values] [code values] ... 
~~~~~


**profile** builds a profile in a plane using a moving point and direction. By default, the profile is closed and a face is created. The original point is 0 0, and direction is 1 0 situated in the XY plane. 


| **Code**     |    **Values **    |       **Action** |
| :------------ | :------------- | :---------------- |
| O                 |                     X Y Z      |          Sets the origin of the plane |
| P                 |         DX DY DZ UX UY UZ  |  Sets the normal and X of the plane |
| F                 |                      X Y    |               Sets the first point |
| X                 |                      DX      |             Translates a point along X |
| Y                 |                      DY       |            Translates a point along Y |
| L                 |                      DL        |            Translates a point along direction |
| XX                |                    X           |           Sets point X coordinate |
| YY                |                    Y           |           Sets point Y coordinate |
| T                 |                      DX DY     |         Translates a point |
| TT                |                     X Y        |           Sets a point |
| R                 |                      Angle     |           Rotates direction |
| RR                |                    Angle       |         Sets direction |
| D                 |                     DX DY      |        Sets direction |
| IX                |                      X         |             Intersects with vertical |
| IY                |                      Y         |             Intersects with horizontal |
| C                 |                Radius Angle    |      Arc of circle tangent to direction |


Codes and values are used to define the next point or change the direction. When the profile changes from a straight line to a curve, a tangent is created. All angles are in degrees and can be negative. 

The point [code values] can be repeated any number of times and in any order to create the profile contour. 

| Suffix | Action |
| :----- | :----- |
| No suffix  |             Makes a closed face |
| W          |               Make a closed wire |
| WW         |            Make an open wire |

The profile shape definition is the suffix; no suffix produces a face, *w* is a closed wire, *ww* is an open wire. 

Code letters are not case-sensitive. 

**Example:** 
~~~~~
# to create a trianglular plane using a vertex at the 
origin, in the xy plane 
profile p O 0 0 0 X 1 Y 0 x 1 y 1 
~~~~~

**Example:** 
~~~~~
# to create a contour using the different code 
possibilities 

# two vertices in the xy plane 
profile p F 1 0 x 2 y 1 ww 

# to view from a point normal to the plane 
top 

# add a circular element of 45 degrees 
profile p F 1 0 x 2 y 1 c 1 45 ww 

# add a tangential segment with a length value 1 
profile p F 1 0 x 2 y 1 c 1 45 l 1 ww 

# add a vertex with xy values of 1.5 and 1.5 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 ww 

# add a vertex with the x value 0.2, y value is constant 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 xx 0.2 ww 

# add a vertex with the y value 2 x value is constant 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 yy 2 ww 

# add a circular element with a radius value of 1 and a circular value of 290 degrees 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 xx 0.2 yy 2 c 1 290 

# wire continues at a tangent to the intersection x = 0 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 xx 0.2 yy 2 c 1 290 ix 0 ww 

# continue the wire at an angle of 90 degrees until it intersects the y axis at y= -o.3 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 xx 0.2 yy 2 c 1 290 ix 0 r 90 ix -0.3 ww 

#close the wire 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 xx 0.2 yy 2 c 1 290 ix 0 r 90 ix -0.3 w 

# to create the plane with the same contour 
profile p F 1 0 x 2 y 1 c 1 45 l 1 tt 1.5 1.5 xx 0.2 yy 2 c 1 290 ix 0 r 90 ix -0.3 
~~~~~

@subsubsection occt_draw_7_2_5   bsplineprof

Syntax:      
~~~~~
bsplineprof name [S face] [W WW] 
~~~~~

* for an edge : \<digitizes\> ... <mouse button 2>
* to end profile : <mouse button 3>

Builds a profile in the XY plane from digitizes. By default the profile is closed and a face is built. 

**bsplineprof** creates a 2d profile from bspline curves using the mouse as the input. *MB1* creates the points, *MB2* finishes the current curve and starts the next curve, *MB3* closes the profile. 

The profile shape definition is the suffix; no suffix produces a face, **w** is a closed wire, **ww** is an open wire. 

**Example:** 
~~~~~
#to view the xy plane 
top 
#to create a 2d curve with the mouse 
bsplineprof res 
# click mb1 to start the curve 
# click mb1 to create the second vertex 
# click mb1 to create a curve 
== 
#click mb2 to finish the curve and start a new curve 
== 
# click mb1 to create the second curve 
# click mb3 to create the face 
~~~~~

@subsubsection occt_draw_7_2_6  mkoffset

Syntax:      
~~~~~
mkoffset result face/compound of wires nboffset stepoffset 
~~~~~

**mkoffset** creates a parallel wire in the same plane using a face or an existing continuous set of wires as a reference. The number of occurences is not limited. 

The offset distance defines the spacing and the positioning of the occurences. 

**Example:** 
~~~~~
#Create a box and select a face 
box b 1 2 3 
explode b f 
#Create three exterior parallel contours with an offset 
value of 2 
mkoffset r b_1 3 2 
Create one interior parallel contour with an offset 
value of 
0.4 
mkoffset r b_1 1 -0.4 
~~~~~

**Note** that *mkoffset* command must be used with prudence, as angular contours produce offset contours with fillets. Interior parallel contours can produce more than one wire, normally these are refused. In the following example, any increase in the offset value is refused.

**Example:** 
~~~~~
# to create the example contour 
profile p F 0 0 x 2 y 4 tt 1 1 tt 0 4 w 
# to create an incoherent interior offset 
mkoffset r p 1 -0.50 
==p is not a FACE but a WIRE 
BRepFill_TrimEdgeTool: incoherent intersection 
# to create two incoherent wires 
mkoffset r p 1 -0.50 
~~~~~

@subsubsection occt_draw_7_2_7  mkplane, mkface

Syntax:      
~~~~~
mkplane name wire 
mkface name surface [ufirst ulast vfirst vlast] 
~~~~~

**mkplane** generates a face from a planar wire. The planar surface will be constructed with an orientation which keeps the face inside the wire. 

**mkface** generates a face from a surface. Parameter values can be given to trim a rectangular area. The default boundaries are those of the surface. 

**Example:** 
~~~~~
# make a polygonal face 
polyline f 0 0 0 20 0 0 20 10 0 10 10 0 10 20 0 0 20 0 0 0 0 
mkplane f f 

# make a cylindrical face 
cylinder g 10 
trim g g -pi/3 pi/2 0 15 
mkface g g 
~~~~~

@subsubsection occt_draw_7_2_8  mkcurve, mksurface

Syntax:      
~~~~~
mkcurve curve edge 
mksurface name face 
~~~~~

**mkcurve** creates a 3d curve from an edge. The curve will be trimmed to the edge boundaries. 

**mksurface** creates a surface from a face. The surface will not be trimmed. 

**Example:** 
~~~~~
# make a line 
vertex v1 0 0 0 
vertex v2 10 0 0 
edge e v1 v2 
~~~~~

@subsubsection occt_draw_7_2_9  pcurve

Syntax:      

~~~~~
pcurve [name edgename] facename 
~~~~~

Extracts the 2d curve of an edge on a face. If only the face is specified, the command extracts all the curves and colors them according to their orientation. This is useful in checking to see if the edges in a face are correctly oriented, i.e. they turn counter-clockwise. To make curves visible, use a fitted 2d view. 

**Example:** 
~~~~~
# view the pcurves of a face 
plane p 
trim p p -1 1 -1 1 
mkface p p 
av2d; # a 2d view 
pcurve p 
2dfit 
~~~~~

@subsubsection occt_draw_7_2_10  chfi2d

Syntax:      
~~~~~
chfi2d result face [edge1 edge2 (F radius/CDD d1 d2/CDA d ang) .... 
~~~~~


Creates chamfers and fillets on 2D objects. Select two adjacent edges and: 
  * a radius value
  * two respective distance values
  * a distance value and an angle

The radius value produces a fillet between the two faces. 

The distance is the length value from the edge between the two selected faces in a normal direction. 

**Example:** 

Let us create a 2d fillet: 

~~~~~
top 
profile p x 2 y 2 x -2 
chfi2d cfr p . . F 0.3 
==Pick an object 
#select an edge 
==Pick an object 
#select an edge 
~~~~~

Let us create a 2d chamfer using two distances:
 
~~~~~
profile p x 2 y 2 x -2 
chfi2d cfr p . . CDD 0.3 0.6 
==Pick an object 
#select an edge 
==Pick an object 
#select an edge 
~~~~~

Let us create a 2d chamfer using a defined distance and angle 

~~~~~
top 
profile p x 2 y 2 x -2 
chfi2d cfr p . . CDA 0.3 75 
==Pick an object 
#select an edge 
==Pick an object 
#select an edge 
~~~~~

@subsubsection occt_draw_7_2_11  nproject

Syntax:      
~~~~~
nproject pj e1 e2 e3 ... surf -g -d [dmax] [Tol 
[continuity [maxdeg [maxseg]]] 
~~~~~

Creates a shape projection which is normal to the target surface. 

**Example:**
~~~~~
# create a curved surface 
line l 0 0 0 1 0 0 
trim l l 0 2 
convert l l 

incdeg l 3 
cmovep l 1 0 0.5 0 
cmovep l 3 0 0.5 0 
copy l ll 
translate ll 2 -0.5 0 
mkedge e1 l 
mkedge e2 ll 
wire w e1 e2 
prism p w 0 0 3 
donl p 
#display in four views 
mu4 
fit 
# create the example shape 
circle c 1.8 -0.5 1 0 1 0 1 0 0 0.4 
mkedge e c 
donly p e 
# create the normal projection of the shape(circle) 
nproject r e p 
~~~~~


@subsection occt_draw_7_3  Primitives

Primitive commands make it possible to create simple shapes. They include: 

  * **box** and **wedge** commands.
  * **pcylinder**, **pcone**, **psphere**, **ptorus** commands.
  * **halfspace** command


@subsubsection occt_draw_7_3_1  box, wedge

Syntax:      
~~~~~
box name [x y z] dx dy dz 
wedge name dx dy dz ltx / xmin zmin xmax xmax 
~~~~~

**box** creates a box parallel to the axes with dimensions *dx,dy,dz*. *x,y,z* is the corner of the box. It is the default origin. 

**wedge** creates a box with five faces called a wedge. One face is in the OXZ plane, and has dimensions *dx,dz* while the other face is in the plane *y = dy*. This face either has dimensions *ltx, dz* or is bounded by *xmin,zmin,xmax,zmax*. 

The other faces are defined between these faces. The face in the *y=yd* plane may be degenerated into a line if *ltx = 0*, or a point if *xmin = xmax* and *ymin = ymax*. In these cases, the line and the point both have 5 faces each. To position the wedge use the *ttranslate* and *trotate* commands. 

**Example:** 
~~~~~
# a box at the origin 
box b1 10 20 30 

# another box 
box b2 30 30 40 10 20 30 

# a wedge 
wedge w1 10 20 30 5 

# a wedge with a sharp edge (5 faces) 
wedge w2 10 20 30 0 

# a pyramid 
wedge w3 20 20 20 10 10 10 10 
~~~~~

@subsubsection occt_draw_7_3_2  pcylinder, pcone, psphere, ptorus

Syntax:      
~~~~~
pcylinder name [plane] radius height [angle] 
pcone name [plane] radius1 radius2 height [angle] 
pcone name [plane] radius1 radius2 height [angle] 
psphere name [plane] radius1 [angle1 angle2] [angle] 
ptorus name [plane] radius1 radius2 [angle1 angle2] [angle] 
~~~~~

All these commands create solid blocks in the default coordinate system, using the Z axis as the axis of revolution and the X axis as the origin of the angles. To use another system, translate and rotate the resulting solid or use a plane as first argument to specify a coordinate system. All primitives have an optional last argument which is an angle expressed in degrees and located on the Z axis, starting from the X axis. The default angle is 360. 

**pcylinder** creates a cylindrical block with the given radius and height. 

**pcone** creates a truncated cone of the given height with radius1 in the plane z = 0 and radius2 in the plane z = height. Neither radius can be negative, but one of them can be null. 

**psphere** creates a solid sphere centered on the origin. If two angles, *angle1* and *angle2*, are given, the solid will be limited by two planes at latitude *angle1* and *angle2*. The angles must be increasing and in the range -90,90. 

**ptorus** creates a solid torus with the given radii, centered on the origin, which is a point along the z axis. If two angles increasing in degree in the range 0 – 360 are given, the solid will be bounded by two planar surfaces at those positions on the circle. 

**Example:** 
~~~~~
# a can shape 
pcylinder cy 5 10 

# a quarter of a truncated cone 
pcone co 15 10 10 90 

# three-quarters of sphere 
psphere sp 10 270 

# half torus 
ptorus to 20 5 0 90 
~~~~~

@subsubsection occt_draw_7_3_3  halfspace

Syntax:      
~~~~~
halfspace result face/shell x y z 
~~~~~

**halfspace** creates an infinite solid volume based on a face in a defined direction. This volume can be used to perform the boolean operation of cutting a solid by a face or plane. 

**Example:** 
~~~~~
box b 0 0 0 1 2 3 
explode b f 
==b_1 b_2 b_3 b_4 b_5 b_6 
halfspace hr b_3 0.5 0.5 0.5 
~~~~~


@subsection occt_draw_7_4  Sweeping

Sweeping creates shapes by sweeping out a shape along a defined path: 

  * **prism** sweeps along a direction.
  * **revol** sweeps around an axis.
  * **pipe** sweeps along a wire.
  * **mksweep** and **buildsweep** are commands to create sweeps by defining the arguments and algorithms.
  * **thrusections** creates a sweep from wire in different planes.


@subsubsection occt_draw_7_4_1  prism

Syntax:      
~~~~~
prism result base dx dy dz [Copy | Inf | SemiInf] 
~~~~~

Creates a new shape by sweeping a shape in a direction. Any shape can be swept: a vertex gives an edge; an edge gives a face; and a face gives a solid. 

The shape is swept along the vector *dx dy dz*. The original shape will be shared in the result unless *Copy* is specified. If *Inf* is specified the prism is infinite in both directions. If *SemiInf* is specified the prism is infinite in the *dx,dy,dz* direction, and the length of the vector has no importance. 

**Example:** 
~~~~~
# sweep a planar face to make a solid 
polyline f 0 0 0 10 0 0 10 5 0 5 5 0 5 15 0 0 15 0 0 0 0 
mkplane f f 
~~~~~

@subsubsection occt_draw_7_4_2  revol

Syntax:      
~~~~~
revol result base x y z dx dy dz angle [Copy] 
~~~~~

Creates a new shape by sweeping a base shape through an angle along the axis *x,y,z dx,dy,dz*. As with the prism command, the shape can be of any type and is not shared if *Copy* is specified. 

**Example:** 
~~~~~
# shell by wire rotation 
polyline w 0 0 0 10 0 0 10 5 0 5 5 0 5 15 0 0 15 0 
revol s w 20 0 0 0 1 0 90 
~~~~~


@subsubsection occt_draw_7_4_3  pipe

Syntax:      
~~~~~
pipe name wire_spine Profile 
~~~~~

Creates a new shape by sweeping a shape known as the profile along a wire known as the spine. 

**Example:** 
~~~~~
# sweep a circle along a bezier curve to make a solid 
pipe 

beziercurve spine 4 0 0 0 10 0 0 10 10 0 20 10 0 
mkedge spine spine 
wire spine spine 
circle profile 0 0 0 1 0 0 2 
mkedge profile profile 
wire profile profile 
mkplane profile profile 
pipe p spine profile 
~~~~~

@subsubsection occt_draw_7_4_4  mksweep, addsweep, setsweep, deletesweep, buildsweep, simulsweep

Syntax:      
~~~~~
mksweep wire 
addsweep wire[vertex][-M][-C] [auxiilaryshape]
deletesweep wire 
setsweep options [arg1 [arg2 [...]]] 
simulsweep r [n] [option] 
buildsweep [r] [option] [Tol] 
~~~~~

options are : 
 * *-FR* : Tangent and Normal are defined by a Frenet trihedron 
 * *-CF* : Tangent is given by Frenet, the Normal is computed to minimize the torsion 
 * *-DX Surf* : Tangent and Normal are given by Darboux trihedron, surf must be a shell or a face 
 * *-CN dx dy dz* : BiNormal is given by *dx dy dz* 
 * *-FX Tx Ty TZ [Nx Ny Nz]* : Tangent and Normal are fixed 
 * *-G guide* 

These commands are used to create a shape from wires. One wire is designated as the contour that defines the direction; it is called the spine. At least one other wire is used to define the the sweep profile. 
* **mksweep** initializes the sweep creation and defines the wire to be used as the spine. 
* **addsweep** defines the wire to be used as the profile. 
* **deletesweep** cancels the choice of profile wire, without leaving the mksweep mode. You can re-select a profile wire. 
* **setsweep** commands the algorithms used for the construction of the sweep. 
* **simulsweep** can be used to create a preview of the shape. [n] is the number of sections that are used to simulate the sweep. 
* **buildsweep** creates the sweep using the arguments defined by all the commands. 

**Example:** 
~~~~~
#create a sweep based on a semi-circular wire using the 
Frenet algorithm 
#create a circular figure 
circle c2 0 0 0 1 0 0 10 
trim c2 c2 -pi/2 pi/2 
mkedge e2 c2 
donly e2 
wire w e2 
whatis w 
mksweep w 
# to display all the options for a sweep 
setsweep 
#to create a sweep using the Frenet algorithm where the 
#normal is computed to minimise the torsion 
setsweep -CF 
addsweep w -R 
# to simulate the sweep with a visual approximation 
simulsweep w 3 
~~~~~

@subsubsection occt_draw_7_4_5  thrusections

Syntax:  
~~~~~
thrusections [-N] result issolid isruled wire1 wire2 [..wire..] 
~~~~~

**thrusections** creates a shape using wires that are positioned in different planes. Each wire selected must have the same number of edges and vertices. 
A bezier curve is generated between the vertices of each wire. The option *[-N]* means that no check is made on wires for direction. 

**Example:** 
~~~~~
#create three wires in three planes 
polyline w1 0 0 0 5 0 0 5 5 0 2 3 0 
polyline w2 0 1 3 4 1 3 4 4 3 1 3 3 
polyline w3 0 0 5 5 0 5 5 5 5 2 3 5 
# create the shape 
thrusections th issolid isruled w1 w2 w3 
==thrusections th issolid isruled w1 w2 w3 
Tolerances obtenues   -- 3d : 0 
-- 2d : 0 
~~~~~


@subsection occt_draw_7_5  Topological transformation

Transformations are applications of matrices. When the transformation is nondeforming, such as translation or rotation, the object is not copied. The topology localcoordinate system feature is used. The copy can be enforced with the **tcopy** command. 

  * **tcopy** makes a copy of the structure of a shape.
  * **ttranslate**, **trotate**, **tmove**, **reset** move a shape.
  * **tmirror**, **tscale** always modify the shape.


@subsubsection occt_draw_7_5_1   tcopy

Syntax: 
~~~~~
tcopy name toname [name toname ...] 
~~~~~

Copies the structure of one shape, including the geometry, into another, newer shape. 

**Example:** 
~~~~~
# create an edge from a curve and copy it 
beziercurve c 3 0 0 0 10 0 0 20 10 0 
mkedge e1 c 
ttranslate e1 0 5 0 
tcopy e1 e2 
ttranslate e2 0 5 0 
# now modify the curve, only e1 and e2 will be modified 
~~~~~

@subsubsection occt_draw_7_5_2   tmove, treset

Syntax:      
~~~~~
tmove name [name ...] shape 
reset name [name ...] 
~~~~~

**tmove** and **reset** modify the location, or the local coordinate system of a shape. 

**tmove** applies the location of a given shape to other shapes. **reset** restores one or several shapes it to its or their original coordinate system(s). 

**Example:** 
~~~~~
# create two boxes 
box b1 10 10 10 
box b2 20 0 0 10 10 10 
# translate the first box 
ttranslate b1 0 10 0 
# and apply the same location to b2 
tmove b2 b1 
# return to original positions 
reset b1 b2 
~~~~~

@subsubsection occt_draw_7_5_3   ttranslate, trotate

Syntax:      
~~~~~
ttranslate [name ...] dx dy dz 
trotate [name ...] x y z dx dy dz angle 
~~~~~

**ttranslate** translates a set of shapes by a given vector, and **trotate** rotates them by a given angle around an axis. Both commands only modify the location of the shape. 
When creating multiple shapes, the same location is used for all the shapes. (See *toto.tcl* example below. Note that the code of this file can also be directly executed in interactive mode.) 

Locations are very economic in the data structure because multiple occurences of an object share the topological description. 

**Example:** 
~~~~~
# make rotated copies of a sphere in between two cylinders 
# create a file source toto.tcl 
# toto.tcl code: 
for {set i 0} {$i  360} {incr i 20} { 
copy s s$i 
trotate s$i 0 0 0 0 0 1 $i 
} 

# create two cylinders 
pcylinder c1 30 5 
copy c1 c2 
ttranslate c2 0 0 20 

#create a sphere 
psphere s 3 
ttranslate s 25 0 12.5 

# call the source file for multiple copies 
source toto.tcl 
~~~~~

@subsubsection occt_draw_7_5_4   tmirror, tscale

Syntax:      
~~~~~
tmirror name x y z dx dy dz 
tscale name x y z scale 
~~~~~

* **tmirror** makes a mirror copy of a shape about a plane x,y,z dx,dy,dz. 

* **Tscale** applies a central homotopic mapping to a shape. 

**Example:** 
~~~~~
# mirror a portion of cylinder about the YZ plane 
pcylinder c1 10 10 270 
copy c1 c2 
tmirror c2 15 0 0 1 0 0 
# and scale it 
tscale c1 0 0 0 0.5 
~~~~~


@subsection occt_draw_7_6  Old Topological operations

  *  **fuse**, **cut**, **common** are boolean operations. 
  *  **section**, **psection** compute sections. 
  *  **sewing** joins two or more shapes. 


@subsubsection occt_draw_7_6_1  fuse, cut, common

Syntax:      
~~~~~
fuse name shape1 shape2 
cut name shape1 shape2 
common name shape1 shape2 
~~~~~

**fuse** creates a new shape by a boolean operation on two existing shapes. The new shape contains both originals intact. 

**cut** creates a new shape which contains all parts of the second shape but only the first shape without the intersection of the two shapes. 

**common** creates a new shape which contains only what is in common between the two original shapes in their intersection. 

**Example:** 
~~~~~
# all four boolean operations on a box and a cylinder 

box b 0 -10 5 20 20 10 
pcylinder c 5 20 

fuse s1 b c 
ttranslate s1 40 0 0 

cut s2 b c 
ttranslate s2 -40 0 0 

cut s3 c b 
ttranslate s3 0 40 0 

common s4 b c 
ttranslate s4 0 -40 0 
~~~~~


@subsubsection occt_draw_7_6_2  section, psection

Syntax:      
~~~~~
section result shape1 shape2 
psection name shape plane 
~~~~~

**section** creates a compound object consisting of the edges for the intersection curves on the faces of two shapes. 

**psection** creates a planar section consisting of the edges for the intersection curves on the faces of a shape and a plane. 

**Example:** 
~~~~~
# section line between a cylinder and a box 
pcylinder c 10 20 
box b 0 0 5 15 15 15 
trotate b 0 0 0 1 1 1 20 
section s b c 

# planar section of a cone 
pcone c 10 30 30 
plane p 0 0 15 1 1 2 
psection s c p 
~~~~~

@subsubsection occt_draw_7_6_3  sewing

Syntax:      
~~~~~
sewing result [tolerance] shape1 shape2 ... 
~~~~~

**Sewing** joins shapes by connecting their adjacent or near adjacent edges. Adjacency can be redefined by modifying the tolerance value. 

**Example:** 
~~~~~
# create two adjacent boxes 
box b 0 0 0 1 2 3 
box b2 0 2 0 1 2 3 
sewing sr b b2 
whatis sr 
sr is a shape COMPOUND FORWARD Free Modified 
~~~~~

@subsection occt_draw_7_7  New Topological operations


The new algorithm of Boolean operations avoids a large number of weak points and limitations presented in the old boolean operation algorithm. 


@subsubsection occt_draw_7_7_1  bop, bopfuse, bopcut, boptuc, bopcommon,

* **bop** defines *shape1* and *shape2* subject to ulterior Boolean operations 
* **bopfuse** creates a new shape by a boolean operation on two existing shapes. The new shape contains both originals intact. 
* **bopcut** creates a new shape which contains all parts of the second shape but only the first shape without the intersection of the two shapes. 
* **boptuc** is a reverced **bopcut**. 
* **bopcommon** creates a new shape which contains only whatever is in common between the two original shapes in their intersection. 

Syntax:      
~~~~~
bop shape1 shape2 
bopcommon result 
bopfuse result 
bopcut result 
boptuc result 
~~~~~

These commands have short variants: 

~~~~~
bcommon result shape1 shape2 
bfuse result shape1 shape2 
bcut result shape1 shape2 
~~~~~


**bop** fills data structure (DS) of boolean operation for *shape1* and *shape2*. 
**bopcommon, bopfuse, bopcut, boptuc** commands are used after **bop** command. After one **bop** command it is possible to call several commands from the list above. For example:

~~~~~
bop S1 S2
bopfuse R
~~~~~ 


**Example:** 

Let us produce all four boolean operations on a box and a cylinder: 

~~~~~
box b 0 -10 5 20 20 10 
pcylinder c 5 20 

# fills data structure 
bop b c 

bopfuse s1 
ttranslate s1 40 0 0 

bopcut s2 
ttranslate s2 -40 0 0 

boptuc s3 
ttranslate s3 0 40 0 

bopcommon s4 
ttranslate s4 0 -40 0 
~~~~~

Now use short variants of the commands: 

~~~~~
bfuse s11 b c 
ttranslate s11 40 0 100 

bcut s12 b c 
ttranslate s12 -40 0 100 

bcommon s14 b c 
ttranslate s14 0 -40 100 
~~~~~

@subsubsection occt_draw_7_7_2  bopsection

Syntax:      
~~~~~
bop shape1 shape2 
bopsection result 
~~~~~

* **bopsection** creates a compound object consisting of the edges for the intersection curves on the faces of two shapes.
* **bop** fills data structure (DS) of boolean operation for *shape1* and *shape2*. 
* **bopsection** command used after **bop** command.
 
Short variant syntax:      
~~~~~
bsection result shape1 shape2 [-2d/-2d1/-2s2] [-a] 
~~~~~

* <i>-2d</i>  -  PCurves are computed on both parts. 
* <i>-2d1</i> - PCurves are computed on first part. 
* <i>-2d2</i> - PCurves are computed on second part. 
* <i>-a</i>  -   built geometries  are approximated. 

**Example:** 

Let us build a section line between a cylinder and a box 
~~~~~
pcylinder c 10 20 
box b 0 0 5 15 15 15 
trotate b 0 0 0 1 1 1 20 
bop b c 
bopsection s 
# Short variant: 
bsection s2 b c 
~~~~~

@subsubsection occt_draw_7_7_3  bopcheck, bopargshape

Syntax:      
~~~~~
bopcheck shape 
bopargcheck shape1 [[shape2] [-F/O/C/T/S/U] [/R|F|T|V|E|I|P]] [#BF] 
~~~~~

**bopcheck** checks a shape for self-interference. 

**bopargcheck** checks the validity of argument(s) for boolean operations. 

* Boolean Operation - (by default a section is made) : 
  * **F** (fuse) 
  * **O** (common) 
  * **C** (cut) 
  * **T** (cut21) 
  * **S** (section) 
  * **U** (unknown) 
* Test Options - (by default all options are enabled) : 
  * **R** (disable small edges (shrank range) test) 
  * **F** (disable faces verification test) 
  * **T** (disable tangent faces searching test) 
  * **V** (disable test possibility to merge vertices) 
  * **E** (disable test possibility to merge edges) 
  * **I** (disable self-interference test) 
  * **P** (disable shape type test) 
* Additional Test Options :
  * **B** (stop test on first faulty found) - by default it is off; 
  * **F** (full output for faulty shapes) - by default the output is made in a short format.

**Note** that Boolean Operation and Test Options are used only for a couple of argument shapes, except for <b>I</b> and <b>P</b> options that are always used to test a couple of shapes as well as a single shape.

**Example:** 
~~~~~
# checks a shape on self-interference 
box b1 0 0 0 1 1 1 
bopcheck b1 

# checks the validity of argument for boolean cut operations 
box b2 0 0 0 10 10 10 
bopargcheck b1 b2 -C 
~~~~~

@subsection occt_draw_7_8  Drafting and blending

Drafting is creation of a new shape by tilting faces through an angle. 

Blending is the creation of a new shape by rounding edges to create a fillet. 

  * Use the **depouille** command for drafting.
  * Use the **chamf** command to add a chamfer to an edge
  * Use the **blend** command for simple blending.
  * Use **fubl** for a fusion + blending operation.
  * Use **buildevol**, **mkevol**, **updatevol** to realize varying radius blending.


@subsubsection occt_draw_7_8_1  depouille

Syntax: 
~~~~~
dep result shape dirx diry dirz face angle x y x dx dy dz [face angle...] 
~~~~~

Creates a new shape by drafting one or more faces of a shape. 

Identify the shape(s) to be drafted, the drafting direction, and the face(s) with an angle and an axis of rotation for each face. You can use dot syntax to identify the faces. 

**Example:** 
~~~~~
# draft a face of a box 
box b 10 10 10 
explode b f 
== b_1 b_2 b_3 b_4 b_5 b_6 

dep a b 0 0 1 b_2 10 0 10 0 1 0 5 
~~~~~

@subsubsection occt_draw_7_8_2  chamf

Syntax:      
~~~~~
chamf newname shape edge face S dist 
chamf newname shape edge face dist1 dist2 
chamf newname shape edge face A dist angle 
~~~~~

Creates a chamfer along the edge between faces using: 

  * a equal distances from the edge
  * the edge, a face and distance, a second distance
  * the edge, a reference face and an angle

Use the dot syntax to select the faces and edges. 

**Examples:**

Let us create a chamfer based on equal distances from the edge (45 degree angle):
~~~~~
# create a box 
box b 1 2 3 
chamf ch b . . S 0.5 
==Pick an object 
# select an edge 
==Pick an object 
# select an adjacent face 
~~~~~

Let us create a chamfer based on different distances from the selected edge:
~~~~~
box b 1 2 3 
chamf ch b . . 0.3 0.4 
==Pick an object 
# select an edge 
==Pick an object 
# select an adjacent face
~~~~~
 
Let us create a chamfer based on a distance from the edge and an angle:
 
~~~~~
box b 1 2 3 
chamf ch b . . A 0.4 30 
==Pick an object 
# select an edge 
==Pick an object 
# select an adjacent face 
~~~~~

@subsubsection occt_draw_7_8_3  blend

Syntax:      
~~~~~
blend result object rad1 ed1 rad2 ed2 ... [R/Q/P] 
~~~~~

Creates a new shape by filleting the edges of an existing shape. The edge must be inside the shape. You may use the dot syntax. Note that the blend is propagated to the edges of tangential planar, cylindrical or conical faces. 

**Example:** 
~~~~~
# blend a box, click on an edge 
box b 20 20 20 
blend b b 2 . 
==tolerance ang : 0.01 
==tolerance 3d : 0.0001 
==tolerance 2d : 1e-05 
==fleche : 0.001 
==tolblend 0.01 0.0001 1e-05 0.001 
==Pick an object 
# click on the edge you want ot fillet 

==COMPUTE: temps total 0.1s dont : 
==- Init + ExtentAnalyse 0s 
==- PerformSetOfSurf 0.02s 
==- PerformFilletOnVertex 0.02s 
==- FilDS 0s 
==- Reconstruction 0.06s 
==- SetRegul 0s 
~~~~~

@subsubsection occt_draw_7_8_4  fubl

Syntax:      
~~~~~
fubl name shape1 shape2 radius
~~~~~ 
 
Creates a boolean fusion of two shapes and then blends (fillets) the intersection edges using the given radius. 

**Example:** 
~~~~~
# fuse-blend two boxes 
box b1 20 20 5 
copy b1 b2 
ttranslate b2 -10 10 3 
fubl a b1 b2 1 
~~~~~


@subsubsection occt_draw_7_8_5  mkevol, updatevol, buildevol

Syntax:      
~~~~~
mkevol result object (then use updatevol) [R/Q/P] 
updatevol edge u1 radius1 [u2 radius2 ...] 
buildevol 
~~~~~

These three commands work together to create fillets with evolving radii. 

* **mkevol** allows specifying the shape and the name of the result. It returns the tolerances of the fillet. 
* **updatevol** allows describing the filleted edges you want to create. For each edge, you give a set of coordinates: parameter and radius and the command prompts you to pick the edge of the shape which you want to modify. The parameters will be calculated along the edges and the radius function applied to the whole edge. 
* **buildevol** produces the result described previously in **mkevol** and **updatevol**. 

**Example:** 
~~~~~
# makes an evolved radius on a box 
box b 10 10 10 
mkevol b b 
==tolerance ang : 0.01 
==tolerance 3d : 0.0001 
==tolerance 2d : 1e-05 
==fleche : 0.001 
==tolblend 0.01 0.0001 1e-05 0.001 

# click an edge 
updatevol . 0 1 1 3 2 2 
==Pick an object 

buildevol 
==Dump of SweepApproximation 
==Error 3d = 1.28548881203818e-14 
==Error 2d = 1.3468326936926e-14 , 
==1.20292299999388e-14 
==2 Segment(s) of degree 3 

==COMPUTE: temps total 0.91s dont : 
==- Init + ExtentAnalyse 0s 
==- PerformSetOfSurf 0.33s 
==- PerformFilletOnVertex 0.53s 
==- FilDS 0.01s 
==- Reconstruction 0.04s 
==- SetRegul 0s 
~~~~~


@subsection occt_draw_7_9  Topological analysis

Analysis of shapes includes commands to compute length, area, volumes and inertial properties. 

  * Use **lprops**, **sprops**, **vprops** to compute integral properties.
  * Use **bounding** to display the bounding box of a shape.
  * Use **distmini** to calculate the minimum distance between two shapes.


@subsubsection occt_draw_7_9_1  lprops, sprops, vprops

Syntax:      
~~~~~
lprops shape 
sprops shape 
vprops shape 
~~~~~

* **lprops** computes the mass properties of all edges in the shape with a linear density of 1;
* **sprops** of all faces with a surface density of 1;
* **vprops** of all solids with a density of 1. 

All three commands print the mass, the coordinates of the center of gravity, the matrix of inertia and the moments. Mass is either the length, the area or the volume. The center and the main axis of inertia are displayed. 

**Example:** 
~~~~~
# volume of a cylinder 
pcylinder c 10 20 
vprops c 
== results 
Mass : 6283.18529981086 

Center of gravity : 
X = 4.1004749224903e-06 
Y = -2.03392858349861e-16 
Z = 9.9999999941362 

Matrix of Inertia : 
366519.141445068                    5.71451850691484e-12 
0.257640437382627 
5.71451850691484e-12                366519.141444962 
2.26823064169991e-10                0.257640437382627 
2.26823064169991e-10                314159.265358863 

Moments : 
IX = 366519.141446336 
IY = 366519.141444962 
I.Z = 314159.265357595 
~~~~~


@subsubsection occt_draw_7_9_2   bounding

Syntax:      
~~~~~
bounding shape 
~~~~~

Displays the bounding box of a shape. The bounding box is a cuboid created with faces parallel to the x, y, and z planes. The command returns the dimension values of the the box, *xmin ymin zmin xmax ymax zmax.* 

**Example:** 
~~~~~
# bounding box of a torus 
ptorus t 20 5 
bounding t 
==-27.059805107309852              -27.059805107309852 - 
5.0000001000000003 
==27.059805107309852               27.059805107309852 
5.0000001000000003 
~~~~~

@subsubsection occt_draw_7_9_3  distmini

Syntax:      
~~~~~
distmini name Shape1 Shape2 
~~~~~

Calculates the minimum distance between two shapes. The calculation returns the number of solutions, If more than one solution exists. The options are displayed in the viewer(red) and the results are listed in the shell window. The *distmini* lines are considered as shapes which have a value v. 

**Example:** 
~~~~~
box b 0 0 0 10 20 30 
box b2 30 30 0 10 20 30 
distmini d1 b b2 
==the distance value is : 22.3606797749979 
==the number of solutions is :2 

==solution number 1 
==the type of the solution on the first shape is 0 
==the type of the solution on the second shape is 0 
==the coordinates of the point on the first shape are: 
==X=10 Y=20 Z=30 
==the coordinates of the point on the second shape 
are: 
==X=30 Y=30 Z=30 

==solution number 2: 
==the type of the solution on the first shape is 0 
==the type of the solution on the second shape is 0 
==the coordinates of the point on the first shape are: 
==X=10 Y=20 Z=0 
==the coordinates of the point on the second shape 
are: 
==X=30 Y=30 Z=0 

==d1_val d1 d12 
~~~~~

@subsection occt_draw_7_10  Surface creation

Surface creation commands include surfaces created from boundaries and from spaces between shapes. 
  * **gplate** creates a surface from a boundary definition.
  * **filling** creates a surface from a group of surfaces.

@subsubsection occt_draw_7_10_1   gplate,

Syntax: 
~~~~~
gplate result nbrcurfront nbrpntconst [SurfInit] [edge 0] [edge tang (1:G1;2:G2) surf]...[point] [u v tang (1:G1;2:G2) surf] ... 
~~~~~

Creates a surface from a defined boundary. The boundary can be defined using edges, points, or other surfaces. 

**Example:**
~~~~~
plane p 
trim p p -1 3 -1 3 
mkface p p 

beziercurve c1 3 0 0 0 1 0 1 2 0 0 
mkedge e1 c1 
tcopy e1 e2 
tcopy e1 e3 

ttranslate e2 0 2 0 
trotate e3 0 0 0 0 0 1 90 
tcopy e3 e4 
ttranslate e4 2 0 0 
# create the surface 
gplate r1 4 0 p e1 0 e2 0 e3 0 e4 0 
== 
======== Results =========== 
DistMax=8.50014503228635e-16 
* GEOMPLATE END* 
Calculation time: 0.33 
Loop number: 1 
Approximation results 
Approximation error : 2.06274907619957e-13 
Criterium error : 4.97600631215754e-14 

#to create a surface defined by edges and passing through a point 
# to define the border edges and the point 
plane p 
trim p p -1 3 -1 3 
mkface p p 

beziercurve c1 3 0 0 0 1 0 1 2 0 0 
mkedge e1 c1 
tcopy e1 e2 
tcopy e1 e3 

ttranslate e2 0 2 0 
trotate e3 0 0 0 0 0 1 90 
tcopy e3 e4 
ttranslate e4 2 0 0 
# to create a point 
point pp 1 1 0 
# to create the surface 
gplate r2 4 1 p e1 0 e2 0 e3 0 e4 0 pp 
== 
======== Results =========== 
DistMax=3.65622157610934e-06 
* GEOMPLATE END* 
Calculculation time: 0.27 
Loop number: 1 
Approximation results 
Approximation error : 0.000422195884750181 
Criterium error : 3.43709808053967e-05 
~~~~~

@subsubsection occt_draw_7_10_2   filling, fillingparam

Syntax:      
~~~~~
filling result nbB nbC nbP [SurfInit] [edge][face]order... 
edge[face]order... point/u v face order... 
~~~~~

Creates a surface between borders. This command uses the **gplate** algorithm but creates a surface that is tangential to the adjacent surfaces. The result is a smooth continuous surface based on the G1 criterion. 

To define the surface border: 

  * enter the number of edges, constraints, and points
  * enumerate the edges, constraints and points

The surface can pass through other points. These are defined after the border definition. 

You can use the *fillingparam* command to access the filling parameters. 

The options are: 

 * <i>-l</i> : to list current values 
 * <i>-i</i> : to set default values 
 * <i>-rdeg nbPonC nbIt anis </i> : to set filling options 
 * <i>-c t2d t3d tang tcur </i> : to set tolerances 
 * <i>-a maxdeg maxseg </i> : Approximation option 

**Example:** 
~~~~~
# to create four curved survaces and a point 
plane p 
trim p p -1 3 -1 3 
mkface p p 

beziercurve c1 3 0 0 0 1 0 1 2 0 0 
mkedge e1 c1 
tcopy e1 e2 
tcopy e1 e3 

ttranslate e2 0 2 0 
trotate e3 0 0 0 0 0 1 90 
tcopy e3 e4 
ttranslate e4 2 0 0 

point pp 1 1 0 

prism f1 e1 0 -1 0 
prism f2 e2 0 1 0 
prism f3 e3 -1 0 0 
prism f4 e4 1 0 0 

# to create a tangential surface 
filling r1 4 0 0 p e1 f1 1 e2 f2 1 e3 f3 1 e4 f4 1 
# to create a tangential surface passing through point pp 
filling r2 4 0 1 p e1 f1 1 e2 f2 1 e3 f3 1 e4 f4 1 pp# 
# to visualise the surface in detail 
isos r2 40 
# to display the current filling parameters 
fillingparam -l 
== 
Degree = 3 
NbPtsOnCur = 10 
NbIter = 3 
Anisotropie = 0 
Tol2d = 1e-05 
Tol3d = 0.0001 
TolAng = 0.01 
TolCurv = 0.1 

MaxDeg = 8 
MaxSegments = 9 
~~~~~


@subsection occt_draw_7_11  Complex Topology

Complex topology is the group of commands that modify the topology of shapes. This includes feature modeling. 


@subsubsection occt_draw_7_11_1  offsetshape, offsetcompshape

Syntax:      
~~~~~
offsetshape r shape offset [tol] [face ...] 
offsetcompshape r shape offset [face ...] 
~~~~~

**offsetshape** and **offsetcompshape** assign a thickness to the edges of a shape. The *offset* value can be negative or positive. This value defines the thickness and direction of the resulting shape. Each face can be removed to create a hollow object. 

The resulting shape is based on a calculation of intersections. In case of simple shapes such as a box, only the adjacent intersections are required and you can use the **offsetshape** command. 

In case of complex shapes, where intersections can occur from non-adjacent edges and faces, use the **offsetcompshape** command. **comp** indicates complete and requires more time to calculate the result. 

The opening between the object interior and exterior is defined by the argument face or faces. 

**Example:** 
~~~~~
box b1 10 20 30 
explode b1 f 
== b1_1 b1_2 b1_3 b1_4 b1_5 b1_6 
offsetcompshape r b1 -1 b1_3 
~~~~~

@subsubsection occt_draw_7_11_2  featprism, featdprism, featrevol, featlf, featrf

Syntax:      
~~~~~
featprism shape element skface Dirx Diry Dirz Fuse(0/1/2) Modify(0/1) 
featdprism shape face skface angle Fuse(0/1/2) Modify(0/1) 
featrevol shape element skface Ox Oy Oz Dx Dy Dz Fuse(0/1/2) Modify(0/1) 
featlf shape wire plane DirX DirY DirZ DirX DirY DirZ Fuse(0/1/2) Modify(0/1) 
featrf shape wire plane X Y Z DirX DirY DirZ Size Size Fuse(0/1/2) Modify(0/1) 
featperform prism/revol/pipe/dprism/lf result [[Ffrom] Funtil] 
featperformval prism/revol/dprism/lf result value 
~~~~~

**featprism** loads the arguments for a prism with contiguous sides normal to the face. 

**featdprism** loads the arguments for a prism which is created in a direction normal to the face and includes a draft angle. 

**featrevol** loads the arguments for a prism with a circular evolution. 

**featlf** loads the arguments for a linear rib or slot. This feature uses planar faces and a wire as a guideline. 

**featrf** loads the arguments for a rib or slot with a curved surface. This feature uses a circular face and a wire as a guideline. 

**featperform** loads the arguments to create the feature. 

**featperformval** uses the defined arguments to create a feature with a limiting value. 

All the features are created from a set of arguments which are defined when you initialize the feature context. Negative values can be used to create depressions. 

**Examples:** 

Let us create a feature prism with a draft angle and a normal direction :

~~~~~
# create a box with a wire contour on the upper face 
box b 1 1 1 
profil f O 0 0 1 F 0.25 0.25 x 0.5 y 0.5 x -0.5 
explode b f 
# loads the feature arguments defining the draft angle 
featdprism b f b_6 5 1 0 
# create the feature 
featperformval dprism r 1 
==BRepFeat_MakeDPrism::Perform(Height) 
BRepFeat_Form::GlobalPerform () 
 Gluer 
 still Gluer 
 Gluer result 
~~~~~

Let us  create a feature prism with circular direction :

~~~~~
# create a box with a wire contour on the upper face 
box b 1 1 1 
profil f O 0 0 1 F 0.25 0.25 x 0.5 y 0.5 x -0.5 
explode b f 
# loads the feature arguments defining a rotation axis 
featrevol b f b_6 1 0 1 0 1 0 1 0 
featperformval revol r 45 
==BRepFeat_MakeRevol::Perform(Angle) 
BRepFeat_Form::GlobalPerform () 
 Gluer 
 still Gluer 
 Gluer result 
~~~~~


Let us create a slot using the linear feature :

~~~~~
#create the base model using the multi viewer 
mu4 
profile p x 5 y 1 x -3 y -0.5 x -1.5 y 0.5 x 0.5 y 4 x -1 y -5 
prism pr p 0 0 1 
# create the contour for the linear feature 
vertex v1 -0.2 4 0.3 
vertex v2 0.2 4 0.3 
vertex v3 0.2 0.2 0.3 
vertex v4 4 0.2 0.3 
vertex v5 4 -0.2 0.3 
edge e1 v1 v2 
edge e2 v2 v3 
edge e3 v3 v4 
edge e4 v4 v5 
wire w e1 e2 e3 e4 
# define a plane 
plane pl 0.2 0.2 0.3 0 0 1 
# loads the linear feature arguments 
featlf pr w pl 0 0 0.3 0 0 0 0 1 
featperform lf result 
~~~~~

Let us create a rib using the revolution feature :

~~~~~
#create the base model using the multi viewer 
mu4 
pcylinder c1 3 5 
# create the contour for the revolution feature 
profile w c 1 190 WW 
trotate w 0 0 0 1 0 0 90 
ttranslate w -3 0 1 
trotate w -3 0 1.5 0 0 1 180 
plane pl -3 0 1.5 0 1 0 
# loads the revolution feature arguments 
featrf c1 w pl 0 0 0 0 0 1 0.3 0.3 1 1 
featperform rf result 
~~~~~

@subsubsection occt_draw_7_11_3  draft

Syntax: 
~~~~~
draft result shape dirx diry dirz angle shape/surf/length [-IN/-OUT] [Ri/Ro] [-Internal] 
~~~~~

Computes a draft angle surface from a wire. The surface is determined by the draft direction, the inclination of the draft surface, a draft angle, and a limiting distance. 

  * The draft angle is measured in radians.
  * The draft direction is determined by the argument -INTERNAL
  * The argument Ri/Ro deftermines wether the corner edges of the draft surfaces are angular or rounded.
  * Arguments that can be used to define the surface distance are:
   * length, a defined distance
   * shape, until the surface contacts a shape
   * surface, until the surface contacts a surface.

**Note** that the original aim of adding a draft angle to a shape is to produce a shape which can be removed easily from a mould. The Examples below use larger angles than are used normally and the calculation results returned are not indicated.

**Example:** 
~~~~~
# to create a simple profile 
profile p F 0 0 x 2 y 4 tt 0 4 w 
# creates a draft with rounded angles 
draft res p 0 0 1 3 1 -Ro 
# to create a profile with an internal angle 
profile p F 0 0 x 2 y 4 tt 1 1.5 tt 0 4 w 
# creates a draft with rounded external angles 
draft res p 0 0 1 3 1 -Ro 
~~~~~

@subsubsection occt_draw_7_11_4  deform

Syntax:      
~~~~~
deform newname name CoeffX CoeffY CoeffZ
~~~~~

Modifies the shape using the x, y, and z coefficients. You can reduce or magnify the shape in the x,y, and z directions. 
 
**Example:** 
~~~~~
pcylinder c 20 20 
deform a c 1 3 5 
# the conversion to bspline is followed by the 
deformation 
~~~~~


@subsubsection occt_draw_7_11_5 nurbsconvert

Syntax:
 
~~~~~
nurbsconvert result name [result name] 
~~~~~

Changes the NURBS curve definition of a shape to a Bspline curve definition. This conversion is required for assymetric deformation and prepares the arguments for other commands such as **deform**. The conversion can be necessary when transferring shape data to other applications. 


@subsection occt_draw_7_12  Texture Mapping to a Shape

Texture mapping allows you to map textures on a shape. Textures are texture image files and several are predefined. You can control the number of occurrences of the texture on a face, the position of a texture and the scale factor of the texture. 

@subsubsection occt_draw_7_12_1  vtexture

Syntax:      
~~~~~
vtexture NameOfShape TextureFile 
vtexture NameOfShape 
vtexture NameOfShape ? 
vtexture NameOfShape IdOfTexture 
~~~~~

**TextureFile** identifies the file containing the texture you want. The same syntax without **TextureFile** disables texture mapping. The question-mark <b>?</b> lists available textures. **IdOfTexture** allows applying predefined textures. 

@subsubsection occt_draw_7_12_2  vtexscale

Syntax:      
~~~~~
vtexscale NameOfShape ScaleU ScaleV 
vtexscale NameOfShape ScaleUV 
vtexscale NameOfShape 
~~~~~

*ScaleU* and *Scale V* allow scaling the texture according to the U and V parameters individually, while *ScaleUV* applies the same scale to both parameters. 

The syntax without *ScaleU*, *ScaleV* or *ScaleUV* disables texture scaling. 

@subsubsection occt_draw_7_12_3  vtexorigin

Syntax:       
~~~~~
vtexorigin NameOfShape UOrigin VOrigin 
vtexorigin NameOfShape UVOrigin 
vtexorigin NameOfShape 
~~~~~

*UOrigin* and *VOrigin* allow placing the texture according to the U and V parameters individually, while *UVOrigin* applies the same position value to both parameters. 

The syntax without *UOrigin*, *VOrigin* or *UVOrigin* disables origin positioning. 

@subsubsection occt_draw_7_12_4  vtexrepeat

Syntax:       
~~~~~
vtexrepeat NameOfShape URepeat VRepeat 
vtexrepeat NameOfShape UVRepeat 
vtexrepeat NameOfShape 
~~~~~

*URepeat* and *VRepeat* allow repeating the texture along the U and V parameters individually, while *UVRepeat* applies the same number of repetitions for both parameters. 

The same syntax without *URepeat*, *VRepeat* or *UVRepeat* disables texture repetition. 

@subsubsection occt_draw_7_12_5  vtexdefault

Syntax:       
~~~~~
vtexdefault NameOfShape 
~~~~~

*Vtexdefault* sets or resets the texture mapping default parameters. 

The defaults are: 

 * *URepeat = VRepeat = 1* no repetition 
 * *UOrigin = VOrigin = 1*  origin set at (0,0) 
 * *UScale = VScale = 1*  texture covers 100% of the face 
 
 
@section occt_draw_20 General Fuse Algorithm commands

This chapter describes existing commands of Open CASCADE Draw Test Harness that are used for debugging of General Fuse Algorithm (GFA). It is also applicable for Boolean Operations Algorithm (BOA) and Partition Algorithm (PA) because these algorithms are subclasses of GFA. 

See @ref occt_user_guides__boolean_operations "Boolean operations" user's guide for the description of these algorithms.

@subsection occt_draw_20_1 Definitions

The following terms and definitions are used in this document:
* **Objects** – list of shapes that are arguments of the algorithm.
* **Tools** – list of shapes that are arguments of the algorithm. Difference between Objects and Tools is defined by specific requirements of the operations (Boolean Operations, Partition Operation).
* **DS** – internal data structure used by the algorithm (*BOPDS_DS* object).
* **PaveFiller** – intersection part of the algorithm (*BOPAlgo_PaveFiller* object).
* **Builder** – builder part of the algorithm (*BOPAlgo_Builder* object).
* **IDS Index** – the index of the vector *myLines*.

@subsection occt_draw_20_2 General commands

* **bclearobjects** - clears the list of Objects;       
* **bcleartools**       - clears the list of Tools;     
* **baddobjects** *S1 S2...Sn*  - adds shapes *S1, S2, ... Sn* as Objects;      
* **baddtools** *S1 S2...Sn* - adds shapes *S1, S2, ... Sn* as Tools;
* **bfillds** - performs the Intersection Part of the Algorithm;        
* **bbuild** *r* - performs the Building Part of the Algorithm; *r* is the resulting shape.

@subsection occt_draw_20_3 Commands for Intersection Part

All commands listed below  are available when the Intersection Part of the algorithm is done (i.e. after the command *bfillds*).

@subsubsection occt_draw_20_3_1 bopds
        
Syntax: 
~~~~
bopds –v [e, f]       
~~~~

Displays:
* all BRep shapes of arguments that are in the DS [default];
* <i>–v</i> : only vertices of arguments that are in the DS;
* <i>–e</i> : only edges of arguments that are in the DS;
* <i>–f</i> : only faces of arguments that are in the DS.

@subsubsection occt_draw_20_3_2 bopdsdump

Prints contents of the DS. 

Example:

~~~~
 Draw[28]> bopdsdump
 *** DS ***
 Ranges:2                       number of ranges
 range: 0 33            indices for range 1
 range: 34 67           indices for range 2
 Shapes:68              total number of source shapes
 0 : SOLID { 1 }
 1 : SHELL { 2 12 22 26 30 32 }
 2 : FACE { 4 5 6 7 8 9 10 11 }
 3 : WIRE { 4 7 9 11 }
 4 : EDGE { 5 6 }
 5 : VERTEX { }
 6 : VERTEX { }
 7 : EDGE { 8 5 }
 8 : VERTEX { }
~~~~

@code 0 : SOLID { 1 } @endcode has the following meaning:
* *0* – index in the DS;
* *SOLID* – type of the shape;
* <i>{ 1 }</i> – a DS index of the successors.

@subsubsection occt_draw_20_3_3 bopindex

Syntax:
~~~~
bopindex S
~~~~
Prints DS index of shape *S*.

@subsubsection occt_draw_20_3_4 bopiterator

Syntax:
~~~~~
bopiterator [t1 t2]
~~~~~

Prints pairs of DS indices of source shapes that are intersected in terms of bounding boxes.

<i>[t1 t2]</i> are types of the shapes:
* *7* - vertex;
* *6* - edge;
* *4* – face.

Example:
~~~~
 Draw[104]> bopiterator 6 4
 EF: ( z58 z12 )
 EF: ( z17 z56 )
 EF: ( z19 z64 )
 EF: ( z45 z26 )
 EF: ( z29 z36 )
 EF: ( z38 z32 )
~~~~

* *bopiterator 6 4* prints pairs of indices for types: edge/face;
* *z58 z12* - DS indices of intersecting edge and face.


@subsubsection occt_draw_20_3_5 bopinterf

Syntax: 
~~~~
bopinterf t
~~~~

Prints contents of *myInterfTB* for the type of interference *t*:
* *t=0* : vertex/vertex;
* *t=1* : vertex/edge;
* *t=2* : edge/edge;
* *t=3* : vertex/face;
* *t=4* : edge/face.

Example:
~~~~
 Draw[108]> bopinterf 4
 EF: (58, 12, 68), (17, 56, 69), (19, 64, 70), (45, 26, 71), (29, 36, 72), (38, 32, 73), 6 EF found.
~~~~

Here, record <i>(58, 12, 68)</i> means:
* *58* – a DS index of the edge;
* *12* – a DS index of the face;
* *68* – a DS index of the new vertex.

@subsubsection occt_draw_20_3_6 bopsp   

Displays split edges. 

Example:
~~~~
 Draw[33]> bopsp
 edge 58 : z58_74 z58_75
 edge 17 : z17_76 z17_77
 edge 19 : z19_78 z19_79
 edge 45 : z45_80 z45_81
 edge 29 : z29_82 z29_83
 edge 38 : z38_84 z38_85
~~~~

* *edge 58* – 58 is a DS index of the original edge.
* *z58_74 z58_75* – split edges, where 74, 75 are DS indices of the split edges.

@subsubsection occt_draw_20_3_7 bopcb

Syntax:
~~~~
bopcb [nE]
~~~~

Prints Common Blocks for:
* all source edges (by default);
* the source edge with the specified index *nE*.

Example:
~~~~
 Draw[43]> bopcb 17
 -- CB:
 PB:{ E:71 orE:17 Pave1: { 68 3.000 } Pave2: { 18 10.000 } }
 Faces: 36
~~~~

This command dumps common blocks for the source edge with index 17. 
* *PB* – information about the Pave Block;
        * *71* – a DS index of the split edge
        * *17* – a DS index of the original edge
* <i>Pave1 : { 68 3.000 }</i> – information about the Pave:
        * *68* – a DS index of the vertex of the pave
        * *3.000* – a parameter of vertex 68 on edge 17
* *Faces: 36* – 36 is a DS index of the face the common block belongs to. 


@subsubsection occt_draw_20_3_8 bopfin

Syntax:

~~~~
bopfin nF       
~~~~
Prints Face Info about IN-parts for the face with DS index *nF*.

Example:
~~~~
 Draw[47]> bopfin 36
 pave blocks In:
 PB:{ E:71 orE:17 Pave1: { 68 3.000 } Pave2: { 18 10.000 } }
 PB:{ E:75 orE:19 Pave1: { 69 3.000 } Pave2: { 18 10.000 } }
 vrts In:
 18
~~~~


* <i>PB:{ E:71 orE:17 Pave1: { 68 3.000 } Pave2: { 18 10.000 } }</i> – information about the Pave Block; 
* <i>vrts In ... 18 – 18</i> a DS index of the vertex IN the face.

@subsubsection occt_draw_20_3_9 bopfon

Syntax:
~~~~
bopfon nF
~~~~
Print Face Info about ON-parts for the face with DS index *nF*.

Example:
~~~~
 Draw[58]> bopfon 36
 pave blocks On:
 PB:{ E:72 orE:38 Pave1: { 69 0.000 } Pave2: { 68 10.000 } }
 PB:{ E:76 orE:45 Pave1: { 69 0.000 } Pave2: { 71 10.000 } }
 PB:{ E:78 orE:43 Pave1: { 71 0.000 } Pave2: { 70 10.000 } }
 PB:{ E:74 orE:41 Pave1: { 68 0.000 } Pave2: { 70 10.000 } }
 vrts On:
 68 69 70 71
~~~~

* <i>PB:{ E:72 orE:38 Pave1: { 69 0.000 } Pave2: { 68 10.000 } }</i> – information about the Pave Block; 
* <i>vrts On: ... 68 69 70 71 – 68, 69, 70, 71 </i> DS indices of the vertices ON the face.

@subsubsection occt_draw_20_3_10 bopwho

Syntax:
~~~~
bopwho nS
~~~~

Prints the information about the shape with DS index *nF*.

Example:
~~~~
 Draw[116]> bopwho 5
 rank: 0
~~~~

* *rank: 0* – means that shape 5 results from the Argument with index 0.

Example:
~~~~
 Draw[118]> bopwho 68
 the shape is new
 EF: (58, 12),
 FF curves: (12, 56),
 FF curves: (12, 64),
~~~~

This means that shape 68 is a result of the following interferences:
* *EF: (58, 12)* – edge 58 / face 12
* *FF curves: (12, 56)* – edge from the intersection curve between faces 12 and 56
* *FF curves: (12, 64)* – edge from the intersection curve between faces 12 and 64

@subsubsection occt_draw_20_3_11 bopnews

Syntax:
~~~~
bopnews -v [-e]
~~~~

* <i>-v</i> - displays all new vertices produced during the operation;
* <i>-e</i> - displays all new edges produced during the operation.

@subsection occt_draw_20_4      Commands for the Building Part

The commands listed below are available when the Building Part of the algorithm is done (i.e. after the command *bbuild*).

@subsubsection occt_draw_20_4_1 bopim

Syntax: 

~~~~
bopim S
~~~~
Shows the compound of shapes that are images of shape *S* from the argument.

 
@section occt_draw_8 Data Exchange commands

This chapter presents some general information about Data Exchange (DE) operations. 

DE commands are intended for translation files of various formats (IGES,STEP) into OCCT shapes with their attributes (colors, layers etc.) 

This files include a number of entities. Each entity has its own number in the file which we call label and denote as # for a STEP file and D for an IGES file. Each file has entities called roots (one or more). A full description of such entities is contained in the Users' Guides 
* for <a href="user_guides__step.html#occt_step_1">STEP format</a> and
* for <a href="user_guides__iges.html#occt_iges_1">IGES format</a>. 

Each Draw session has an interface model, which is a structure for keeping various information. 

The first step of translation is loading information from a file into a model. 
The second step is creation of an OpenCASCADE shape from this model. 

Each entity from a file has its own number in the model (num). During the translation a map of correspondences between labels(from file) and numbers (from model) is created. 

The model and the map are used for working with most of DE commands. 

@subsection occt_draw_8_1  IGES commands 

@subsubsection occt_draw_8_1_1  igesread

Syntax:      
~~~~~
igesread <file_name> <result_shape_name> [<selection>]
~~~~~

Reads an IGES file to an OCCT shape. This command will interactively ask the user to select a set of entities to be converted. 


| N | Mode | Description |
| :-- | :-- | :---------- |
| 0 | End | finish conversion and exit igesbrep |
| 1 | Visible roots | convert only visible roots |
| 2 | All roots | convert all roots |
| 3 | One entity | convert entity with number provided by the user |
| 4 | Selection | convert only entities contained in selection |


After the selected set of entities is loaded the user will be asked how loaded entities should be converted into OCCT shapes (e.g., one shape per root or one shape for all the entities). It is also possible to save loaded shapes in files, and to cancel loading. 

The second parameter of this command defines the name of the loaded shape. If several shapes are created, they will get indexed names. For instance, if the last parameter was *s*, they will be *s_1, ... s_N*. 

<i>\<selection\></i> specifies the scope of selected entities in the model, by default it is *xst-transferrable-roots*.  If we use symbol <i>*</i> as <i>\<selection\></i> all roots will be translated. 

See also the detailed description of <a href="user_guides__iges.html#occt_iges_2_3_4">Selecting IGES entities</a>.

**Example:**
~~~~~
# translation all roots from file 
igesread /disk01/files/model.igs a  * 
~~~~~

@subsubsection occt_draw_8_1_2   tplosttrim

Syntax:      
~~~~~
tplosttrim [<IGES_type>] 
~~~~~

Sometimes the trimming contours of IGES faces (i.e., entity 141 for 143, 142 for 144) can be lost during translation due to fails. This command gives us a number of lost trims and the number of corresponding IGES entities. 
It outputs the rank and numbers of faces that lost their trims and their numbers for each type (143, 144, 510) and their total number. If a face lost several of its trims it is output only once. 
Optional parameter <i>\<IGES_type\></i> can be *0TrimmedSurface, BoundedSurface* or *Face* to specify the only type of IGES faces. 

**Example:**
~~~~~
tplosttrim TrimmedSurface 
~~~~~

@subsubsection occt_draw_8_1_3  brepiges

Syntax:      
~~~~~
brepiges <shape_name> <filename.igs>
~~~~~

Writes an OCCT shape to an IGES file. 

**Example:** 
~~~~~    
# write shape with name aa to IGES file 
brepiges aa /disk1/tmp/aaa.igs 
== unit (write) : MM 
== mode  write  : Faces 
==   To modifiy : command  param 
== 1 Shapes written, giving 345 Entities 
==  Now, to write a file, command : writeall filename 
==  Output on file : /disk1/tmp/aaa.igs 
==  Write OK 
~~~~~

@subsection occt_draw_8_2  STEP commands 

These commands are used during the translation of STEP models. 


@subsubsection occt_draw_8_2_1  stepread

Syntax:      
~~~~~
stepread file_name result_shape_name [selection] 
~~~~~

Read a STEP file to an OCCT shape. 
This command will interactively ask the user to select a set of entities to be converted: 

| N | Mode | Description |
| :---- | :---- | :---- |  
| 0 | End | Finish transfer and exit stepread | 
| 1 | root with rank 1 | Transfer first root | 
| 2 | root by its rank | Transfer root specified by its rank | 
| 3 | One entity | Transfer entity with a number provided by the user | 
| 4 | Selection | Transfer only entities contained in selection | 

After the selected set of entities is loaded the user will be asked how loaded entities should be converted into OCCT shapes. 
The second parameter of this command defines the name of the loaded shape. If several shapes are created, they will get indexed names. For instance, if the last parameter was *s*, they will be *s_1, ... s_N*. 
<i>\<selection\></i> specifies the scope of selected entities in the model.  If we use symbol <i>*</i> as <i>\<selection\></i> all roots will be translated. 

See also the detailed description of <a href="user_guides__step.html#occt_step_2_3_6">Selecting STEP entities</a>.

**Example:**
~~~~~
# translation all roots from file 
stepread /disk01/files/model.stp a  * 
~~~~~

@subsubsection occt_draw_8_2_2   stepwrite

Syntax:      
~~~~~
stepwrite mode shape_name file_name 
~~~~~

Writes an OCCT shape to a STEP file. 

The following  modes are available : 
    * *a* - as is – mode is selected automatically depending on the type & geometry of the shape; 
    * *m* - *manifold_solid_brep* or *brep_with_voids* 
    * *f* - *faceted_brep* 
    * *w* - *geometric_curve_set* 
    * *s* - *shell_based_surface_model* 
 
For further information see <a href="#user_guides__step.html#occt_step_6_5">Writing a STEP file</a>. 

**Example:**

Let us write shape *a* to a STEP file in mode *0*. 

~~~~~
stepwrite 0 a /disk1/tmp/aaa.igs 
~~~~~


@subsection occt_draw_8_3  General commands 

These are auxilary commands used for the analysis of result of translation of IGES and STEP files. 

@subsubsection occt_draw_8_3_1  count

Syntax:      
~~~~~
count <counter> [<selection>] 
~~~~~

Calculates statistics on the entities in the model and outputs a count of entities. 

The optional selection argument, if specified, defines a subset of entities, which are to be taken into account. The first argument should be one of the currently defined counters. 

| Counter | Operation |
| :-------- | :-------- | 
| xst-types | Calculates how many entities of each OCCT type exist | 
| step214-types | Calculates how many entities of each STEP type exist |

**Example:**
~~~~~
count xst-types 
~~~~~

@subsubsection occt_draw_8_3_2 data

Syntax:      
~~~~~
data <symbol>
~~~~~

Obtains general statistics on the loaded data. 
The information printed by this command depends on the symbol specified. 

**Example:**
~~~~~
# print full information about warnings and fails 
data c 
~~~~~

| Symbol | Output |
| :------ | :------ |
| g | Prints the information contained in the header of the file |
| c or f | Prints messages generated during the loading of the STEP file (when the procedure of the integrity of the loaded data check is performed) and the resulting statistics (f works only with fail messages while c with both fail and warning messages) |
| t | The same as c or f, with a list of failed or warned entities |
| m or l | The same as t but also prints a status for each entity | 
| e | Lists all entities of the model with their numbers, types, validity status etc. |
| R | The same as e but lists only root entities |



@subsubsection occt_draw_8_3_3  elabel

Syntax:      
~~~~~
elabel <num>
~~~~~

Entities in the IGES and STEP files are numbered in the succeeding order. An entity can be identified either by its number or by its label. Label is the letter ‘#'(for STEP, for IGES use ‘D’) followed by the rank. This command gives us a label for an entity with a known number. 

**Example:**
~~~~~
elabel 84 
~~~~~

@subsubsection occt_draw_8_3_4  entity

Syntax:      
~~~~~
entity <#(D)>_or_<num> <level_of_information>
~~~~~

The content of an IGES or STEP entity can be obtained by using this command. 
Entity can be determined by its number or label. 
<i>\<level_of_information\></i> has range [0-6]. You can get more information about this level using this command without parameters. 

**Example:**
~~~~~
# full information for STEP entity with label 84 
entity #84 6 
~~~~~

@subsubsection occt_draw_8_3_5  enum

Syntax:      
~~~~~
enum <#(D)> 
~~~~~

Prints a number for the entity with a given label. 

**Example:**
~~~~~
# give a number for IGES entity with label 21 
enum D21 
~~~~~

@subsubsection occt_draw_8_3_6  estatus

Syntax:      
~~~~~
estatus <#(D)>_or_<num>
~~~~~

The list of entities referenced by a given entity and the list of entities referencing to it can be obtained by this command. 

**Example:**
~~~~~
estatus #315 
~~~~~

@subsubsection occt_draw_8_3_7  fromshape

Syntax:      
~~~~~
fromshape <shape_name>
~~~~~

Gives the number of an IGES or STEP entity corresponding to an OCCT shape. If no corresponding entity can be found and if OCCT shape is a compound the command explodes it to subshapes and try to find corresponding entities for them. 

**Example:**
~~~~~
fromshape a_1_23 
~~~~~

@subsubsection occt_draw_8_3_8  givecount

Syntax:
~~~~~
givecount <selection_name> [<selection_name>]
~~~~~


Prints a number of loaded entities defined by the selection argument.
Possible values of \<selection_name\> you can find in the “IGES FORMAT Users’s Guide”.

**Example:**
~~~~~
givecount xst-model-roots 
~~~~~

@subsubsection occt_draw_8_3_9  givelist

Syntax:      
~~~~~
givelist <selection_name>
~~~~~

Prints a list of a subset of loaded entities defined by the selection argument: 
| Selection | Description |
| :-------- | :----------- |
| xst-model-all | all entities of the model |
| xst-model-roots | all roots |
| xst-pointed | (Interactively) pointed entities (not used in DRAW) |
| xst-transferrable-all | all transferable (recognized) entities |
| xst-transferrable-roots | Transferable roots | 


**Example:**
~~~~~
# give a list of all entities of the model 
givelist xst-model-all 
~~~~~

@subsubsection occt_draw_8_3_10  listcount

Syntax:     listcount \<counter\> [\<selection\> ...]

Prints a list of entities per each type matching the criteria defined by arguments. 
Optional <i>\<selection\></i> argument, if specified, defines a subset of entities, which are to be taken into account. Argument <i>\<counter\></i>  should be one of the currently defined counters: 

| Counter     | Operation |
| :-----      | :------   |
| xst-types   | Calculates how many entities of each OCCT type exist |
| iges-types  | Calculates how many entities of each IGES type and form exist |
| iges-levels | Calculates how many entities lie in different IGES levels |

**Example:**
~~~~~
listcount xst-types 
~~~~~

@subsubsection occt_draw_8_3_11  listitems

Syntax:      
~~~~~
listitems 
~~~~~

This command prints a list of objects (counters, selections etc.) defined in the current session. 


@subsubsection occt_draw_8_3_12  listtypes

Syntax:      
~~~~~
listtypes [<selection_name> ...]
~~~~~

Gives a list of entity types which were encountered in the last loaded file (with a number of entities of each type). The list can be shown not for all entities but for a subset of them. This subset is defined by an optional selection argument. 


@subsubsection occt_draw_8_3_13  newmodel

Syntax:      
~~~~~
newmodel 
~~~~~

Clears the current model. 


@subsubsection occt_draw_8_3_14  param

Syntax:      
~~~~~
param [<parameter>] [<value>]
~~~~~

This command is used to manage translation parameters. 
Command without arguments gives a full list of parameters with current values. 
Command with <i>\<parameter\></i> (without <i><value></i>) gives us the current value of this parameter and all possible values for it. Command with <i><value></i> sets this new value to <i>\<parameter\></i>.

**Example:**

Let us get the information about possible schemes for writing STEP file :

~~~~~
param write.step.schema 
~~~~~

@subsubsection occt_draw_8_3_15  sumcount

Syntax:      
~~~~~
sumcount <counter> [<selection> ...]
~~~~~

Prints only a number of entities per each type matching the criteria defined by arguments. 

**Example:**
~~~~~
sumcount xst-types 
~~~~~

@subsubsection occt_draw_8_3_16  tpclear

Syntax:      
~~~~~
tpclear  
~~~~~

Clears the map of correspondences between IGES or STEP entities and OCCT shapes. 



@subsubsection occt_draw_8_3_17  tpdraw

Syntax:      
~~~~~
tpdraw <#(D)>_or_<num>
~~~~~

**Example:**
~~~~~
tpdraw 57 
~~~~~

@subsubsection occt_draw_8_3_18  tpent

Syntax:      
~~~~~
tpent <#(D)>_or_<num>
~~~~~

Get information about the result of translation of the given IGES or STEP entity.

**Example:**
~~~~~
tpent \#23 
~~~~~

@subsubsection occt_draw_8_3_19  tpstat

Syntax:      
~~~~~
tpstat [*|?]<symbol> [<selection>]
~~~~~


Provides all statistics on the last transfer, including a list of transferred entities with mapping from IGES or STEP to OCCT types, as well as fail and warning messages. The parameter <i>\<symbol\></i> defines what information will be printed: 

* *g* - General statistics (a list of results and messages)
* *c* - Count of all warning and fail messages
* *C* - List of all warning and fail messages
* *f* - Count of all fail messages
* *F* - List of all fail messages
* *n* - List of all transferred roots
* *s* - The same, with types of source entity and the type of result
* *b* - The same, with messages
* *t* - Count of roots for geometrical types
* *r* - Count of roots for topological types
* *l* - The same, with the type of the source entity

The sign \* before parameters *n, s, b, t, r* makes it work on all entities (not only on roots).

The sign ? before *n, s, b, t* limits the scope of information to invalid entities. 

Optional argument \<selection\> can limit the action of the command to the selection, not to all entities. 

To get help, run this command without arguments. 

**Example:**
~~~~~
# translation ratio on IGES faces 
tpstat *l iges-faces 
~~~~~

@subsubsection occt_draw_8_3_20  xload

Syntax:      
~~~~~
xload <file_name>
~~~~~

This command loads an IGES or STEP file into memory (i.e. to fill the model with data from the file) without creation of an OCCT shape. 

**Example:**
~~~~~
xload /disk1/tmp/aaa.stp 
~~~~~


@subsection occt_draw_8_4  Overview of XDE commands 

These commands are used for translation of IGES and STEP files into an XCAF document (special document is inherited from CAF document and is intended for Extended Data Exchange (XDE) ) and working with it. XDE translation allows reading and writing of shapes with additional attributes – colors, layers etc. All commands can be divided into the following groups: 
  * XDE translation commands
  * XDE general commands
  * XDE shape’s commands
  * XDE color’s commands
  * XDE layer’s commands
  * XDE property’s commands

Reminding: All operations of translation are performed with parameters managed by command  <a href="#occt_draw_8_3_14">the command *param*</a>.

@subsubsection occt_draw_8_4_1  ReadIges

Syntax:      
~~~~~
ReadIges document file_name 
~~~~~

Reads information from an IGES file to an XCAF document. 

**Example:**
~~~~~
ReadIges D /disk1/tmp/aaa.igs 
==> Document saved with name D 
~~~~~

@subsubsection occt_draw_8_4_2  ReadStep

Syntax:      
~~~~~
ReadStep <document> <file_name>
~~~~~

Reads information from a STEP file to an XCAF document. 

**Example:**
~~~~~
ReadStep D /disk1/tmp/aaa.stp 
== Document saved with name D 
~~~~~

@subsubsection occt_draw_8_4_3  WriteIges

Syntax:      
~~~~~
WriteIges <document> <file_name>
~~~~~

**Example:**
~~~~~
WriteIges D /disk1/tmp/aaa.igs 
~~~~~

@subsubsection occt_draw_8_4_4  WriteStep

Syntax:      
~~~~~
WriteStep <document> <file_name>
~~~~~

Writes information from an XCAF document to a STEP file. 

**Example:**
~~~~~
WriteStep D /disk1/tmp/aaa.stp 
~~~~~

@subsubsection occt_draw_8_4_5  XFileCur

Syntax:      
~~~~~
XFileCur  
~~~~~

Returns the name of file which is set as the current one in the Draw session. 

**Example:**
~~~~~
XFileCur 
== *as1-ct-203.stp* 
~~~~~

@subsubsection occt_draw_8_4_6  XFileList

Syntax:      
~~~~~
XFileList  
~~~~~

Returns a list all files that were transferred by the last transfer. This command is  meant (assigned) for the assemble step file. 

**Example:**
~~~~~
XFileList 
==> *as1-ct-Bolt.stp* 
==> *as1-ct-L-Bracktet.stp* 
==> *as1-ct-LBA.stp* 
==> *as1-ct-NBA.stp* 
==> … 
~~~~~

@subsubsection occt_draw_8_4_7  XFileSet

Syntax:      
~~~~~
XFileSet <filename> 
~~~~~

Sets the current file taking it from the components list of the assemble file. 

**Example:**
~~~~~
XFileSet as1-ct-NBA.stp 
~~~~~

@subsubsection occt_draw_8_4_8  XFromShape

Syntax:      
~~~~~
XFromShape <shape>
~~~~~

This command is similar to <a href="#occt_draw_8_3_7">the command *fromshape*</a>, but gives additional information about the file name. It is useful if a shape was translated from several files. 

**Example:**
~~~~~
XFromShape a 
==> Shape a: imported from entity 217:#26 in file as1-ct-Nut.stp 
~~~~~

@subsection occt_draw_8_5  XDE general commands 

@subsubsection occt_draw_8_5_1  XNewDoc

Syntax:      
~~~~~
XNewDoc <document>
~~~~~

Creates a new XCAF document. 

**Example:**
~~~~~
XNewDoc D 
~~~~~

@subsubsection occt_draw_8_5_2  XShow

Syntax:      
~~~~~
XShow <document> [ <label1> … ]
~~~~~

Shows a shape from a given label in the 3D viewer. If the label is not given – shows all shapes from the document. 

**Example:**
~~~~~
# show shape from label 0:1:1:4 from document D 
XShow D 0:1:1:4 
~~~~~

@subsubsection occt_draw_8_5_3  XStat

Syntax:      
~~~~~
XStat <document>
~~~~~

Prints common information from an XCAF document. 

**Example:**
~~~~~
XStat D 
==>Statistis of shapes in the document: 
==>level N 0 : 9 
==>level N 1 : 18 
==>level N 2 : 5 
==>Total number of labels for shapes in the document = 32 
==>Number of labels with name = 27 
==>Number of labels with color link = 3 
==Number of labels with layer link = 0 
==>Statistis of Props in the document: 
==>Number of Centroid Props = 5 
==>Number of Volume Props = 5 
==>Number of Area Props = 5 
==>Number of colors = 4 
==>BLUE1 RED YELLOW BLUE2 
==>Number of layers = 0 
~~~~~

@subsubsection occt_draw_8_5_4  XWdump

Syntax:      
~~~~~
XWdump <document> <filename>
~~~~~

Saves the contents of the viewer window as an image (XWD, png or BMP file). 
<i>\<filename\></i> must have a corresponding extention. 

**Example:**
~~~~~
XWdump D /disk1/tmp/image.png 
~~~~~

@subsubsection occt_draw_8_5_5  Xdump

Syntax:      
~~~~~
Xdump <document> [int deep {0|1}]
~~~~~

Prints information about the tree structure of the document. If parameter 1 is given, then the tree is printed with a link to shapes. 

**Example:**
~~~~~
Xdump D 1 
==> ASSEMBLY 0:1:1:1 L-BRACKET(0xe8180448) 
==> ASSEMBLY 0:1:1:2 NUT(0xe82151e8) 
==> ASSEMBLY 0:1:1:3 BOLT(0xe829b000) 
==> ASSEMBLY 0:1:1:4 PLATE(0xe8387780) 
==> ASSEMBLY 0:1:1:5 ROD(0xe8475418) 
==> ASSEMBLY 0:1:1:6 AS1(0xe8476968) 
==>    ASSEMBLY 0:1:1:7 L-BRACKET-ASSEMBLY(0xe8476230) 
==>       ASSEMBLY 0:1:1:1 L-BRACKET(0xe8180448) 
==>       ASSEMBLY 0:1:1:8 NUT-BOLT-ASSEMBLY(0xe8475ec0) 
==>               ASSEMBLY 0:1:1:2 NUT(0xe82151e8) 
==>               ASSEMBLY 0:1:1:3 BOLT(0xe829b000) 
etc. 
~~~~~

@subsection occt_draw_8_6  XDE shape commands 

@subsubsection occt_draw_8_6_1  XAddComponent

Syntax:      
~~~~~
XAddComponent <document> <label> <shape> 
~~~~~

Adds a component shape to assembly. 

**Example:**

Let us add shape b as component shape to assembly shape from label *0:1:1:1* 

~~~~~
XAddComponent D 0:1:1:1 b 
~~~~~

@subsubsection occt_draw_8_6_2  XAddShape

Syntax:      
~~~~~
XAddShape <document> <shape> [makeassembly=1]
~~~~~

Adds a shape (or an assembly) to a document. If this shape already exists in the document, then prints the label which points to it. By default, a new shape is added as an assembly (i.e. last parameter 1), otherwise it is necessary to pass 0 as the last parameter. 

**Example:**
~~~~~
# add shape b to document D 
XAddShape D b 0 
== 0:1:1:10 
# if pointed shape is compound and last parameter in 
# XAddShape command is used by default (1), then for 
# each subshapes new label is created 
~~~~~

@subsubsection occt_draw_8_6_3  XFindComponent

Syntax:      
~~~~~
XFindComponent <document> <shape>
~~~~~

Prints a sequence of labels of the assembly path. 

**Example:**
~~~~~
XFindComponent D b 
~~~~~

@subsubsection occt_draw_8_6_4  XFindShape

Syntax:      
~~~~~
XFindShape <document> <shape>
~~~~~

Finds and prints a label with an indicated top-level shape. 

**Example:**
~~~~~
XFindShape D a 
~~~~~

@subsubsection occt_draw_8_6_5  XGetFreeShapes

Syntax:      
~~~~~
XGetFreeShapes <document> [shape_prefix]
~~~~~

Print labels or create DRAW shapes for all free shapes in the document. 
If *shape_prefix* is absent – prints labels, else – creates DRAW shapes with names 
<i>shape_prefix</i>_num (i.e. for example: there are 3 free shapes and *shape_prefix* = a therefore shapes will be created with names a_1, a_2 and a_3). 

**Note**: a free shape is a shape to which no other shape refers to. 

**Example:**
~~~~~
XGetFreeShapes D 
== 0:1:1:6 0:1:1:10 0:1:1:12 0:1:1:13 

XGetFreeShapes D sh 
== sh_1 sh_2 sh_3 sh_4 
~~~~~

@subsubsection occt_draw_8_6_6  XGetOneShape

Syntax:      
~~~~~
XGetOneShape <shape> <document>
~~~~~

Creates one DRAW shape for all free shapes from a document. 

**Example:**
~~~~~
XGetOneShape a D 
~~~~~

@subsubsection occt_draw_8_6_7  XGetReferredShape

Syntax:      
~~~~~
XGetReferredShape <document> <label>
~~~~~

Prints a label that contains a top-level shape that corresponds to a shape at a given label. 

**Example:**
~~~~~
XGetReferredShape D 0:1:1:1:1 
~~~~~

@subsubsection occt_draw_8_6_8  XGetShape

Syntax:      
~~~~~
XGetShape <result> <document> <label>
~~~~~

Puts a shape from the indicated label in document to result. 

**Example:**
~~~~~
XGetShape b D 0:1:1:3 
~~~~~

@subsubsection occt_draw_8_6_9  XGetTopLevelShapes

Syntax:      
~~~~~
XGetTopLevelShapes <document>
~~~~~

Prints labels that contain top-level shapes. 

**Example:**
~~~~~
XGetTopLevelShapes D 
== 0:1:1:1 0:1:1:2 0:1:1:3 0:1:1:4 0:1:1:5 0:1:1:6 0:1:1:7 
0:1:1:8 0:1:1:9 
~~~~~

@subsubsection occt_draw_8_6_10  XLabelInfo

Syntax:      
~~~~~
XLabelInfo <document> <label>
~~~~~

Prints information about a shape, stored at an indicated label. 

**Example:** 
~~~~~    
XLabelInfo D 0:1:1:6 
==> There are TopLevel shapes. There is an Assembly. This Shape is not used. 
~~~~~

@subsubsection occt_draw_8_6_11  XNewShape

Syntax:      
~~~~~
XNewShape <document>
~~~~~

Creates a new empty top-level shape. 

**Example:**
~~~~~
XNewShape D 
~~~~~

@subsubsection occt_draw_8_6_12  XRemoveComponent

Syntax:      
~~~~~
XRemoveComponent <document> <label>
~~~~~

Removes a component from the components label. 

**Example:**
~~~~~
XRemoveComponent D 0:1:1:1:1 
~~~~~

@subsubsection occt_draw_8_6_13  XRemoveShape

Syntax:      
~~~~~
XRemoveShape <document> <label>
~~~~~

Removes a shape from a document (by it’s label). 

**Example:**
~~~~~
XRemoveShape D 0:1:1:2 
~~~~~

@subsubsection occt_draw_8_6_14  XSetShape

Syntax:      
~~~~~
XSetShape <document> <label> <shape>
~~~~~

Sets a shape at the indicated label. 

**Example:**
~~~~~
XSetShape D 0:1:1:3 b 
~~~~~


@subsection occt_draw_8_7_  XDE color commands 

@subsubsection occt_draw_8_7_1  XAddColor

Syntax:      
~~~~~
XAddColor <document> <R> <G> <B>
~~~~~

Adds color in document to the color table. Parameters R,G,B are real. 

**Example:**
~~~~~
XAddColor D 0.5 0.25 0.25 
~~~~~

@subsubsection occt_draw_8_7_2  XFindColor

Syntax:      
~~~~~
XFindColor <document> <R> <G> <B>
~~~~~

Finds a label where the indicated color is situated. 

**Example:**
~~~~~
XFindColor D 0.25 0.25 0.5 
==> 0:1:2:2 
~~~~~

@subsubsection occt_draw_8_7_3  XGetAllColors

Syntax:      
~~~~~
XGetAllColors <document> 
~~~~~

Prints all colors that are defined in the document. 

**Example:**
~~~~~
XGetAllColors D 
==> RED DARKORANGE BLUE1 GREEN YELLOW3 
~~~~~

@subsubsection occt_draw_8_7_4  XGetColor

Syntax:      
~~~~~
XGetColor <document> <label>
~~~~~

Returns a color defined at the indicated label from the color table. 

**Example:**
~~~~~
XGetColor D 0:1:2:3 
== BLUE1 
~~~~~

@subsubsection occt_draw_8_7_5  XGetObjVisibility

Syntax:      
~~~~~
XGetObjVisibility <document> {<label>|<shape>}
~~~~~

Returns the visibility of a shape. 

**Example:**
~~~~~
XGetObjVisibility D 0:1:1:4 
~~~~~

@subsubsection occt_draw_8_7_6  XGetShapeColor

Syntax:      
~~~~~
XGetShapeColor <document> <label> <colortype(s|c)>
~~~~~

Returns the color defined by label. If <i>colortype</i>=’s’ – returns surface color, else – returns curve color. 

**Example:**
~~~~~
XGetShapeColor D 0:1:1:4 c 
~~~~~

@subsubsection occt_draw_8_7_7  XRemoveColor

Syntax:      
~~~~~
XRemoveColor <document> <label>
~~~~~

Removes a color from the color table in a document. 

**Example:**
~~~~~
XRemoveColor D 0:1:2:1 
~~~~~

@subsubsection occt_draw_8_7_8  XSetColor

Syntax:      
~~~~~
XSetColor <document> {<label>|<shape>} <R> <G> <B>
~~~~~

Sets an RGB color to a shape given by label. 

**Example:**
~~~~~
XsetColor D 0:1:1:4 0.5 0.5 0. 
~~~~~

@subsubsection occt_draw_8_7_9  XSetObjVisibility

Syntax:      
~~~~~
XSetObjVisibility <document> {<label>|<shape>} {0|1}
~~~~~

Sets the visibility of a shape. 

**Example:**
~~~~~
# set shape from label 0:1:1:4 as invisible 
XSetObjVisibility D 0:1:1:4 0 
~~~~~

@subsubsection occt_draw_8_7_10  XUnsetColor

Syntax:      
~~~~~
XUnsetColor <document> {<label>|<shape>} <colortype>
~~~~~

Unset a color given type (‘s’ or ‘c’) for the indicated shape. 

**Example:**
~~~~~
XUnsetColor D 0:1:1:4 s 
~~~~~


@subsection occt_draw_8_8_  XDE layer commands 

@subsubsection occt_draw_8_8_1  XAddLayer

Syntax:      
~~~~~
XAddLayer <document> <layer>
~~~~~

Adds a new layer in an XCAF document. 

**Example:**
~~~~~
XAddLayer D layer2 
~~~~~

@subsubsection occt_draw_8_8_2  XFindLayer

Syntax:      
~~~~~
XFindLayer <document> <layer>
~~~~~

Prints a label where a layer is situated. 

**Example:**
~~~~~
XFindLayer D Bolt 
== 0:1:3:2 
~~~~~

@subsubsection occt_draw_8_8_3  XGetAllLayers

Syntax:      
~~~~~
XGetAllLayers <document> 
~~~~~

Prints all layers in an XCAF document. 

**Example:**
~~~~~
XGetAllLayers D 
== *0:1:1:3* *Bolt* *0:1:1:9* 
~~~~~

@subsubsection occt_draw_8_8_4  XGetLayers

Syntax:      
~~~~~
XGetLayers <document> {<shape>|<label>}
~~~~~

Returns names of layers, which are pointed to by links of an indicated shape. 

**Example:**
~~~~~
XGetLayers D 0:1:1:3 
== *bolt* *123* 
~~~~~

@subsubsection occt_draw_8_8_5  XGetOneLayer

Syntax:      
~~~~~
XGetOneLayer <document> <label>
~~~~~

Prints the name of a layer at a given label. 

**Example:**
~~~~~
XGetOneLayer D 0:1:3:2 
~~~~~

@subsubsection occt_draw_8_8_6  XIsVisible

Syntax:      
~~~~~
XIsVisible <document> {<label>|<layer>}
~~~~~

Returns 1 if the indicated layer is visible, else returns 0. 

**Example:**
~~~~~
XIsVisible D 0:1:3:1 
~~~~~

@subsubsection occt_draw_8_8_7  XRemoveAllLayers

Syntax:      
~~~~~
XRemoveAllLayers <document> 
~~~~~

Removes all layers from an XCAF document. 

**Example:**
~~~~~
XRemoveAllLayers D 
~~~~~

@subsubsection occt_draw_8_8_8  XRemoveLayer

Syntax:      
~~~~~
XRemoveLayer <document> {<label>|<layer>}
~~~~~

Removes the indicated layer from an XCAF document. 

**Example:**
~~~~~
XRemoveLayer D layer2 
~~~~~

@subsubsection occt_draw_8_8_9  XSetLayer

Syntax:      
~~~~~
XSetLayer XSetLayer <document> {<shape>|<label>} <layer> [shape_in_one_layer {0|1}]

~~~~~
 
Sets a reference between a shape and a layer (adds a layer if it is necessary). 
Parameter <i>\<shape_in_one_layer\></i> shows whether a shape could be in a number of layers or only in one (0 by default). 

**Example:**
~~~~~
XSetLayer D 0:1:1:2 layer2 
~~~~~

@subsubsection occt_draw_8_8_10  XSetVisibility

Syntax:      
~~~~~
XSetVisibility <document> {<label>|<layer>} <isvisible {0|1}>
~~~~~

Sets the visibility of a layer. 

**Example:**
~~~~~
# set layer at label 0:1:3:2 as invisible 
XSetVisibility D 0:1:3:2 0 
~~~~~

@subsubsection occt_draw_8_8_11  XUnSetAllLayers

Syntax:      
~~~~~
XUnSetAllLayers <document> {<label>|<shape>}
~~~~~

Unsets a shape from all layers. 

**Example:**
~~~~~
XUnSetAllLayers D 0:1:1:2 
~~~~~

@subsubsection occt_draw_8_8_12  XUnSetLayer

Syntax:      
~~~~~
XUnSetLayer <document> {<label>|<shape>} <layer>
~~~~~

Unsets a shape from the indicated layer. 

**Example:**
~~~~~
XUnSetLayer D 0:1:1:2 layer1 
~~~~~

@subsection occt_draw_8_9  XDE property commands 

@subsubsection occt_draw_8_9_1  XCheckProps

Syntax:      
~~~~~
XCheckProps <document> [ {0|deflection} [<shape>|<label>] ]
~~~~~

Gets properties for a given shape (*volume*, *area* and <i>centroid</i>) and compares them with the results after internal calculations. If the second parameter is 0, the standard OCCT tool is used for the computation of properties. If the second parameter is not 0, it is processed as a deflection. If the deflection is positive the computation is done by triangulations, if it is negative – meshing is forced. 

**Example:**
~~~~~
# check properties for shapes at label 0:1:1:1 from 
# document using standard Open CASCADE Technology tools 
XCheckProps D 0 0:1:1:1 
== Label 0:1:1:1      ;L-BRACKET* 
==  Area defect:        -0.0 (  0%) 
==  Volume defect:       0.0 (  0%) 
==  CG defect: dX=-0.000, dY=0.000, dZ=0.000 
~~~~~

@subsubsection occt_draw_8_9_2  XGetArea

Syntax:      
~~~~~
XGetArea <document> {<shape>|<label>}
~~~~~

Returns the area of a given shape. 

**Example:**
~~~~~
XGetArea D 0:1:1:1 
== 24628.31815094999 
~~~~~

@subsubsection occt_draw_8_9_3  XGetCentroid

Syntax:      
~~~~~
XGetCentroid <document> {<shape>|<label>}
~~~~~

Returns the center of gravity coordinates of a given shape. 

**Example:**
~~~~~
XGetCentroid D 0:1:1:1 
~~~~~

@subsubsection occt_draw_8_9_4  XGetVolume

Syntax:      
~~~~~
XGetVolume <document> {<shape>|<label>}
~~~~~

Returns the volume of a given shape. 

**Example:**
~~~~~
XGetVolume D 0:1:1:1 
~~~~~

@subsubsection occt_draw_8_9_5  XSetArea

Syntax:      
~~~~~
XSetArea <document> {<shape>|<label>} <area>
~~~~~

Sets new area to attribute list ??? given shape. 

**Example:**
~~~~~
XSetArea D 0:1:1:1 2233.99 
~~~~~

@subsubsection occt_draw_8_9_6  XSetCentroid

Syntax:      
~~~~~
XSetCentroid <document> {<shape>|<label>} <x> <y> <z>
~~~~~

Sets new center of gravity  to the attribute list given shape. 

**Example:**
~~~~~
XSetCentroid D 0:1:1:1 0. 0. 100. 
~~~~~

@subsubsection occt_draw_8_9_7  XSetMaterial

Syntax:      
~~~~~
XSetMaterial <document> {<shape>|<label>} <name> <density(g/cu sm)>
~~~~~ 

Adds a new label with material into the material table in a document, and adds a link to this material to the attribute list of a given shape or a given label. The last parameter sets the density of a pointed material. 

**Example:**
~~~~~
XSetMaterial D 0:1:1:1 Titanium 8899.77 
~~~~~

@subsubsection occt_draw_8_9_8  XSetVolume

Syntax:      
~~~~~
XSetVolume <document> {<shape>|<label>} <volume>
~~~~~

Sets new volume to the attribute list ??? given shape. 

**Example:**
~~~~~
XSetVolume D 0:1:1:1 444555.33 
~~~~~

@subsubsection occt_draw_8_9_9  XShapeMassProps

Syntax:      
~~~~~
XShapeMassProps <document> [ <deflection> [{<shape>|<label>}] ]
~~~~~

Computes and returns real mass and real center of gravity for a given shape or for all shapes in a document. The second parameter is used for calculation of the volume and CG(center of gravity). If it is 0, then the standard CASCADE tool (geometry) is used for computation, otherwise - by triangulations with a given deflection. 

**Example:**
~~~~~
XShapeMassProps D 
== Shape from label : 0:1:1:1 
== Mass = 193.71681469282299 
== CenterOfGravity X = 14.594564763807696,Y = 
    20.20271885211281,Z = 49.999999385313245 
== Shape from label : 0:1:1:2 not have a mass 
etc. 
~~~~~

@subsubsection occt_draw_8_9_10  XShapeVolume

Syntax:      
~~~~~
XShapeVolume <shape> <deflection>
~~~~~

Calculates the real volume of a pointed shape with a given deflection. 

**Example:**
~~~~~
XShapeVolume a 0 
~~~~~

@section occt_draw_9 Shape Healing commands



@subsection occt_draw_9_1 General commands 

@subsubsection occt_draw_9_1_1 bsplres

Syntax:      
~~~~~
bsplres <result> <shape> <tol3d> <tol2d< <reqdegree> <reqnbsegments> <continuity3d> <continuity2d> <PriorDeg> <RationalConvert>
~~~~~

Performs approximations of a given shape (BSpline curves and surfaces or other surfaces) to BSpline with given required parameters. The specified continuity can be reduced if the approximation with a specified continuity was not done successfully. Results are put into the shape, which is given as a parameter result. For a more detailed description see the ShapeHealing User’s Guide (operator: **BSplineRestriction**). 

@subsubsection occt_draw_9_1_2 checkfclass2d

Syntax:      
~~~~~
checkfclass2d <face> <ucoord> <vcoord>
~~~~~

Shows where a point which is given by coordinates is located in relation to a given face – outbound, inside or at the bounds. 

**Example:**
~~~~~
checkfclass2d f 10.5 1.1 
== Point is OUT 
~~~~~

@subsubsection occt_draw_9_1_3 checkoverlapedges

Syntax:      
~~~~~
checkoverlapedges <edge1> <edge2> [<toler> <domaindist>]
~~~~~

Checks the overlapping of two given edges. If the distance between two edges is less than the given value of tolerance then edges are overlapped. Parameter \<domaindist\> sets length of part of edges on which edges are overlapped. 

**Example:**
~~~~~
checkoverlapedges e1 e2 
~~~~~

@subsubsection occt_draw_9_1_4 comtol

Syntax:      
~~~~~
comptol <shape> [nbpoints] [prefix]
~~~~~

Compares the real value of tolerance on curves with the value calculated by standard (using 23 points). The maximal value of deviation of 3d curve from pcurve at given simple points is taken as a real value (371 is by default). Command returns the maximal, minimal and average value of tolerance for all edges and difference between real values and set values. Edges with the maximal value of tolerance and relation will be saved if the ‘prefix’ parameter is given. 

**Example:** 
~~~~~    
comptol h 871 t 

==> Edges tolerance computed by 871 points: 
==> MAX=8.0001130696523449e-008 AVG=6.349346868091096e-009 MIN=0 
==> Relation real tolerance / tolerance set in edge 
==> MAX=0.80001130696523448 AVG=0.06349345591805905 MIN=0 
==> Edge with max tolerance saved to t_edge_tol 
==> Concerned faces saved to shapes t_1, t_2 
~~~~~

@subsubsection occt_draw_9_1_5 convtorevol

Syntax:      
~~~~~
convtorevol <result> <shape>
~~~~~

Converts all elementary surfaces of a given shape into surfaces of revolution. 
Results are put into the shape, which is given as the <i>\<result\></i> parameter. 

**Example:**
~~~~~
convtorevol r a 
~~~~~

@subsubsection occt_draw_9_1_6 directfaces

Syntax:      
~~~~~
directfaces <result> <shape>
~~~~~

Converts indirect surfaces and returns the results into the shape, which is given as the result parameter. 

**Example:**
~~~~~
directfaces r a 
~~~~~

@subsubsection occt_draw_9_1_7 expshape

Syntax:   
~~~~~
expshape <shape> <maxdegree> <maxseg>
~~~~~

Gives statistics for a given shape. This test command is working with Bezier and BSpline entities. 

**Example:**
~~~~~
expshape a 10 10 
==> Number of Rational Bspline curves 128 
==> Number of Rational Bspline pcurves 48 
~~~~~

@subsubsection occt_draw_9_1_8 fixsmall

Syntax:      
~~~~~
fixsmall <result> <shape> [<toler>=1.]
~~~~~

Fixes small edges in given shape by merging adjacent edges with agiven tolerance. Results are put into the shape, which is given as the result parameter. 

**Example:**
~~~~~
fixsmall r a 0.1 
~~~~~

@subsubsection occt_draw_9_1_9 fixsmalledges

Syntax:      
~~~~~
fixsmalledges <result> <shape> [<toler> <mode> <maxangle>]
~~~~~

Searches at least one small edge at a given shape. If such edges have been found, then small edges are merged with a given tolerance. If parameter <i>\<mode\></i> is equal to *Standard_True* (can be given any values, except 2), then  small edges, which can not be merged, are removed, otherwise they are to be kept (*Standard_False* is used by default). Parameter <i>\<maxangle\></i> sets a maximum possible angle for merging two adjacent edges, by default no limit angle is applied (-1). Results are put into the shape, which is given as parameter result. 

**Example:**
~~~~~
fixsmalledges r a 0.1 1 
~~~~~

@subsubsection occt_draw_9_1_10 fixshape

Syntax:      
~~~~~
fixshape <result> <shape> [<preci> [<maxpreci>]] [{switches}]
~~~~~

Performs fixes of all sub-shapes (such as *Solids*, *Shells*, *Faces*, *Wires* and *Edges*) of a given shape. Parameter <i>\<preci\></i> sets a basic precision value, <i>\<maxpreci\></i> sets the maximal allowed tolerance. Results are put into the shape, which is given as parameter result. <b>{switches}</b> allows to tune parameters of ShapeFix 

The following syntax is used: 
* <i>\<symbol\></i> may be
  * "-" to set parameter off, 
  * "+" to set on or  
  * "*" to set default 
* <i>\<parameter\></i> is identified by  letters: 
  * l - FixLackingMode 
  * o - FixOrientationMode 
  * h - FixShiftedMode 
  * m - FixMissingSeamMode 
  * d - FixDegeneratedMode 
  * s - FixSmallMode 
  * i - FixSelfIntersectionMode 
  * n - FixNotchedEdgesMode 
For enhanced message output, use switch '+?' 

**Example:**
~~~~~
fixshape r a 0.001 
~~~~~

@subsubsection occt_draw_9_1_11 fixwgaps

Syntax:      
~~~~~
fixwgaps <result> <shape> [<toler>=0]
~~~~~

Fixes gaps between ends of curves of adjacent edges (both 3d and pcurves) in wires in a given shape with a given tolerance. Results are put into the shape, which is given as parameter result. 

**Example:**
~~~~~
fixwgaps r a 
~~~~~

@subsubsection occt_draw_9_1_12 offsetcurve, offset2dcurve

Syntax:      
~~~~~
offsetcurve <result> <curve> <offset> <direction(as point)>
offset2dcurve <result> <curve> <offset>
~~~~~

**offsetcurve** works with the curve in 3d space, **offset2dcurve** in 2d space. 

Both commands are intended to create a new offset curve by copying the given curve to distance, given by parameter <i>\<offset\></i>. Parameter <i>\<direction\></i> defines direction of the offset curve. It is created as a point. For correct work of these commands the direction of normal of the offset curve must be perpendicular to the plane, the basis curve is located there. Results are put into the curve, which is given as parameter <i>\<result\></i>.  

**Example:**
~~~~~
point pp 10 10 10 
offsetcurve r c 20 pp 
~~~~~

@subsubsection occt_draw_9_1_13 projcurve

Syntax:      
~~~~~
projcurve <edge>|<curve3d>|<curve3d first last>  <X> <Y> <Z>
~~~~~

**projcurve** returns the projection of a given point on a given curve. The curve may be defined by three ways: by giving the edge name, giving the 3D curve and by giving the unlimited curve and limiting it by pointing its start and finish values. 

**Example:** 
~~~~~    
projcurve k_1 0 1 5 
==Edge k_1 Params from 0 to 1.3 
==Precision (BRepBuilderAPI) : 9.9999999999999995e-008  ==Projection : 0  1  5 
==Result : 0  1.1000000000000001  0 
==Param = -0.20000000000000001  Gap = 5.0009999000199947 
~~~~~

@subsubsection occt_draw_9_1_14 projface

Syntax:      
~~~~~
projface <face> <X> <Y> [<Z>]
~~~~~

Returns the projection of a given point to a given face in 2d or 3d space. If two coordinates (2d space) are given then returns coordinates projection of this point in 3d space and vice versa. 

**Example:**
~~~~~
projface a_1 10.0 0.0 
==  Point UV  U = 10  V = 0 
==   =   proj  X = -116  Y = -45  Z = 0 
~~~~~

@subsubsection occt_draw_9_1_15 scaleshape

Syntax:   
~~~~~
scaleshape <result> <shape> <scale>
~~~~~

Returns a new shape, which is the result of scaling of a given shape with a coefficient equal to the parameter <i>\<scale\></i>. Tolerance is calculated for the  new shape as well.

**Example:**
~~~~~
scaleshape r a_1 0.8 
~~~~~

@subsubsection occt_draw_9_1_16 settolerance

Syntax:      
~~~~~
settolerance <shape> [<mode>=v-e-w-f-a] <val>(fix value) or
                   <tolmin> <tolmax>
~~~~~ 

Sets new values of tolerance for a given shape. If the second parameter <i>mode</i> is given, then the tolerance value is set only for these sub shapes. 

**Example:**
~~~~~
settolerance a 0.001 
~~~~~

@subsubsection occt_draw_9_1_17 splitface

Syntax:      
~~~~~
splitface <result> <face> [u usplit1 usplit2...] [v vsplit1 vsplit2 ...]
~~~~~

Splits a given face in parametric space and puts the result into the given parameter <i>\<result\></i>. 
Returns the status of split face. 

**Example:**
~~~~~
# split face f by parameter u = 5 
splitface r f u 5 
==> Splitting by   U:   ,5 
==> Status:  DONE1 
~~~~~

@subsubsection occt_draw_9_1_18 statshape

Syntax:      
~~~~~
statshape <shape> [particul]
~~~~~

Returns the number of sub-shapes, which compose the given shape. For example, the number of solids, number of faces etc.  It also returns the number of geometrical objects or sub-shapes with a specified type, example, number of free faces, number of C0 
surfaces. The last parameter becomes out of date. 

**Example:**
~~~~~
statshape a 
==> Count     Item 
==> -----     ---- 
==> 402     Edge (oriented) 
==> 402     Edge (Shared) 
==> 74      Face 
==> 74      Face (Free) 
==> 804     Vertex (Oriented) 
==> 402     Vertex (Shared) 
==> 78      Wire 
==> 4      Face with more than one wire 
==> 34     bspsur: BSplineSurface 
~~~~~

@subsubsection occt_draw_9_1_19 tolerance

Syntax:
~~~~~
tolerance <shape> [<mode>:D v e f c] [<tolmin> <tolmax>:real]
~~~~~

Returns tolerance (maximal, avg and minimal values)  of all given shapes and tolerance of their *Faces*, *Edges* and *Vertices*. If parameter <i>\<tolmin\></i> or <i>\<tolmax\></i> or both of them are given, then sub-shapes are returned as a result of analys of this shape, which satisfy the given tolerances. If a particular value of entity ((**D**)all shapes  (**v**) *vertices* (**e**) *edges* (**f**) *faces* (**c**) *combined* (*faces*)) is given as the second parameter then only this group will be analyzed for tolerance. 

**Example:**
~~~~~
tolerance a 
==> Tolerance MAX=0.31512672416608001 AVG=0.14901359484722074 MIN=9.9999999999999995e-08 
==> FACE    : MAX=9.9999999999999995e-08 AVG=9.9999999999999995e-08 MIN=9.9999999999999995e-08 
==> EDGE    : MAX=0.31512672416608001 AVG=0.098691334511810405 MIN=9.9999999999999995e-08 
==> VERTEX  : MAX=0.31512672416608001 AVG=0.189076074499648 MIN=9.9999999999999995e-08 

tolerance a v 0.1 0.001 
==>  Analysing Vertices gives 6 Shapes between tol1=0.10000000000000001 and tol2=0.001 , named tol_1 to tol_6 
~~~~~


@subsection occt_draw_9_2 Conversion commands 

@subsubsection occt_draw_9_2_1 DT_ClosedSplit

Syntax:      
~~~~~
DT_ClosedSplit <result> <shape>
~~~~~

Divides all closed faces in the shape (for example cone) and returns result of given shape into shape, which is given as parameter result. Number of faces in resulting shapes will be increased. 
Note: Closed face – it’s face with one or more seam. 

**Example:**
~~~~~
DT_ClosetSplit r a 
~~~~~

@subsubsection occt_draw_9_2_2 DT_ShapeConvert, DT_ShapeConvertRev

Syntax:      
~~~~~
DT_ShapeConvert <result> <shape> <convert2d> <convert3d>
DT_ShapeConvertRev <result> <shape> <convert2d> <convert3d>
~~~~~
 
Both commands are intended for the conversion of 3D, 2D curves to Bezier curves and surfaces to Bezier based surfaces. Parameters convert2d and convert3d take on a value 0 or 1. If the given value is 1, then the conversion will be performed, otherwise it will not be performed. The results are put into the shape, which is given as parameter Result. Command *DT_ShapeConvertRev* differs from *DT_ShapeConvert* by converting all elementary surfaces into surfaces of revolution first. 

**Example:**
~~~~~
DT_ShapeConvert r a 1 1 
== Status: DONE1 
~~~~~

@subsubsection occt_draw_9_2_3 DT_ShapeDivide

Syntax:      
~~~~~
DT_ShapeDivide <result> <shape> <tol>
~~~~~

Divides the shape with C1 criterion and returns the result of geometry conversion of a given shape into the shape, which is given as parameter result. This command illustrates how class *ShapeUpgrade_ShapeDivideContinuity* works. This class allows to convert geometry with a continuity less than the specified continuity to geometry with target continuity. If conversion is not possible then the geometrical object is split into several ones, which satisfy the given tolerance. It also returns the  status shape splitting: 
 * OK      : no splitting was done 
 * Done1 : Some edges were split 
 * Done2 : Surface was split 
 * Fail1    : Some errors occurred 

**Example:**
~~~~~
DT_ShapeDivide r a 0.001 
== Status: OK 
~~~~~

@subsubsection occt_draw_9_2_4 DT_SplitAngle

Syntax:      
~~~~~
DT_SplitAngle <result> <shape> [MaxAngle=95]
~~~~~

Works with all revolved surfaces, like cylinders, surfaces of revolution, etc. This command divides given revolved surfaces into segments so that each resulting segment covers not more than the given *MaxAngle* degrees and puts the result of splitting into the shape, which is given as parameter result. Values of returned status are given above. 
This command illustrates how class *ShapeUpgrade_ShapeDivideAngle* works. 

**Example:**
~~~~~
DT_SplitAngle r a 
== Status: DONE2 
~~~~~

@subsubsection occt_draw_9_2_5 DT_SplitCurve

Syntax:      
~~~~~
DT_SplitCurve <curve> <tol> <split(0|1)>
~~~~~

Divides the 3d curve with C1 criterion and returns the result of splitting of the given curve into a new curve. If the curve had been divided by segments, then each segment is put to an individual result.  This command can correct a given curve at a knot with the given tolerance, if it is impossible, then the given surface is split at that knot. If the last parameter is 1, then 5 knots are added at the given curve, and its surface is split by segments, but this will be performed not for all parametric spaces. 

**Example:**
~~~~~
DT_SplitCurve r c 
~~~~~

@subsubsection occt_draw_9_2_6 DT_SplitCurve2d

Syntax:      
~~~~~
DT_SplitCurve2d Curve Tol Split(0/1) 
~~~~~

Works just as **DT_SplitCurve** (see above), only with 2d curve. 

**Example:**
~~~~~
DT_SplitCurve2d r c 
~~~~~

@subsubsection occt_draw_9_2_7 DT_SplitSurface

Syntax:      
~~~~~
DT_SplitSurface <result> <Surface|GridSurf> <tol> <split(0|1)>
~~~~~

Divides surface with C1 criterion and returns the result of splitting of a given surface into surface, which is given as parameter result. If the surface has been divided into segments, then each segment is put to an individual result.  This command can correct a given C0 surface at a knot with a given tolerance, if it is impossible, then the given surface is split at that knot. If the last parameter is 1, then 5 knots are added to the given surface, and its surface is split by segments, but this will be performed not for all parametric spaces. 

**Example:** 
~~~~~

~~~~~
# split surface with name "su"
DT_SplitSurface res su 0.1 1 
==> single surf 
==> appel a SplitSurface::Init 
==> appel a SplitSurface::Build 
==> appel a SplitSurface::GlobalU/VKnots 
==> nb GlobalU;nb GlobalV=7 2 0 1 2 3 4 5 6.2831853072 0 1 
==> appel a Surfaces 
==> transfert resultat 
==> res1_1_1 res1_2_1 res1_3_1 res1_4_1 res1_5_1 res1_6_1 
~~~~~
~~~~~

@subsubsection occt_draw_9_2_8 DT_ToBspl

Syntax:
~~~~~
DT_ToBspl <result> <shape>
~~~~~

Converts a surface of linear extrusion, revolution and offset surfaces into BSpline surfaces. Returns the result into the shape, which is given as parameter result. 

**Example:** 
~~~~~    
DT_ToBspl res sh 
== error = 5.20375663162094e-08   spans = 10 
==  Surface is aproximated with continuity 2 
~~~~~

@section occt_draw_10 Performance evaluation commands


@subsection occt_draw_10_1 VDrawSphere

Syntax:      
~~~~~
vdrawsphere shapeName Fineness [X=0.0 Y=0.0 Z=0.0] [Radius=100.0] [ToEnableVBO=1] [NumberOfViewerUpdate=1] [ToShowEdges=0] 
~~~~~

Calculates and displays in a given number of steps a sphere with given coordinates, radius and fineness. Returns the information about the properties of the sphere, the time and the amount of memory required to build it. 

This command can be used for visualization performance evaluation instead of the outdated Visualization Performance Meter. 

**Example:** 
~~~~~
vdrawsphere s 200 1 1 1 500 1 
== Compute Triangulation... 
== NumberOfPoints: 39602 
== NumberOfTriangles: 79200 
== Amount of memory required for PolyTriangulation without Normals: 2 Mb 
== Amount of memory for colors: 0 Mb 
== Amount of memory for PolyConnect: 1 Mb 
== Amount of graphic card memory required: 2 Mb 
== Number of scene redrawings: 1 
== CPU user time: 15.6000999999998950 msec 
== CPU system time: 0.0000000000000000 msec 
== CPU average time of scene redrawing: 15.6000999999998950 msec 
~~~~~


@section occt_draw_11 Extending Test Harness with custom commands


The following chapters explain how to extend Test Harness with custom commands and how to activate them using a plug-in mechanism. 


@subsection occt_draw_11_1 Custom command implementation

Custom command implementation has not undergone any changes since the introduction of the plug-in mechanism. The syntax of every command should still be like in the following example. 

**Example:** 
~~~~~
static Standard_Integer myadvcurve(Draw_Interpretor& di, Standard_Integer n, char** a) 
{ 
... 
} 
~~~~~

For examples of existing commands refer to Open CASCADE Technology (e.g. GeomliteTest.cxx). 


@subsection occt_draw_11_2 Registration of commands in Test Harness

To become available in the Test Harness the custom command must be registered in it. This should be done as follows. 

**Example:** 
~~~~~
void MyPack::CurveCommands(Draw_Interpretor& theCommands) 
{ 
... 
char* g = "Advanced curves creation"; 

theCommands.Add ( "myadvcurve", "myadvcurve name p1 p2 p3 – Creates my advanced curve from points", 
                  __FILE__, myadvcurve, g ); 
... 
} 
~~~~~

@subsection occt_draw_11_3 Creating a toolkit (library) as a plug-in

All custom commands are compiled and linked into a dynamic library (.dll on Windows, or .so on Unix/Linux). To make Test Harness recognize it as a plug-in it must respect certain conventions. Namely, it must export function *PLUGINFACTORY()* accepting the Test Harness interpreter object (*Draw_Interpretor*). This function will be called when the library is dynamically loaded during the Test Harness session. 

This exported function *PLUGINFACTORY()* must be implemented only once per library. 

For convenience the *DPLUGIN* macro (defined in the *Draw_PluginMacro.hxx* file) has been provided. It implements the *PLUGINFACTORY()* function as a call to the *Package::Factory()* method and accepts *Package* as an argument. Respectively, this *Package::Factory()* method must be implemented in the library and activate all implemented commands. 

**Example:** 
~~~~~
#include <Draw_PluginMacro.hxx>

void MyPack::Factory(Draw_Interpretor& theDI)
{
...
// 
MyPack::CurveCommands(theDI);
...
}

// Declare entry point PLUGINFACTORY
DPLUGIN(MyPack)
~~~~~

@subsection occt_draw_11_4 Creation of the plug-in resource file

As mentioned above, the plug-in resource file must be compliant with Open CASCADE Technology requirements (see *Resource_Manager.cdl* file for details). In particular, it should contain keys separated from their values by a colon (;:;). 
For every created plug-in there must be a key. For better readability and comprehension it is recommended to have some meaningful name. 
Thus, the resource file must contain a line mapping this name (key) to the library name. The latter should be without file extension (.dll on Windows, .so on Unix/Linux) and without the ;lib; prefix on Unix/Linux. 
For several plug-ins one resource file can be created. In such case, keys denoting plug-ins can be combined into groups, these groups - into their groups and so on (thereby creating some hierarchy). Any new parent key must have its value as a sequence of child keys separated by spaces, tabs or commas. Keys should form a tree without cyclic dependencies. 

**Examples** (file MyDrawPlugin): 
~~~~~
! Hierarchy of plug-ins 
ALL                : ADVMODELING, MESHING 
DEFAULT            : MESHING 
ADVMODELING        : ADVSURF, ADVCURV 

! Mapping from naming to toolkits (libraries) 
ADVSURF            : TKMyAdvSurf 
ADVCURV            : TKMyAdvCurv 
MESHING            : TKMyMesh 
~~~~~

For other examples of the plug-in resource file refer to the <a href="#occt_draw_1_3_2">Plug-in resource file</a> chapter above or to the <i>$CASROOT/src/DrawPlugin</i> file shipped with Open CASCADE Technology. 


@subsection occt_draw_11_5 Dynamic loading and activation

Loading a plug-in and activating its commands is described in the <a href="#occt_draw_1_3_3">Activation of the commands implemented in the plug-in</a> chapter. 

The procedure consists in defining the system variables and using the pload commands in the Test Harness session. 

**Example:** 
~~~~
Draw[]> set env(CSF_MyDrawPluginDefaults) /users/test
Draw[]> pload -MyDrawPlugin ALL
~~~~