+++ /dev/null
-Overview {#mainpage}
-========
-
-@section OCCT_OVW_SECTION_1 Welcome
-
-Welcome to Open CASCADE Technology version 6.7.0, a minor release,
-which introduces a number of new features and improved traditional
-functionality along with some changes over the previous release 6.6.0.
-
-This release makes Open CASCADE Technology even a more powerful and stable
-development platform for 3D modeling and numerical simulation applications.
-
-Open CASCADE Technology 6.7.0 is a full-featured package that allows developing
-applications on Windows and Linux platforms.
-
-@htmlonly<center>@endhtmlonly http://www.opencascade.org
-
-@image html /overview/images/overview_occttransparent.png
-@image latex /overview/images/overview_occttransparent.png
-
-Copyright (c) 2001-2013 OPEN CASCADE S.A.S.
-
-@image html /resources/occt_logo.png
-@image latex /resources/occt_logo.png
-
-@htmlonly</center>@endhtmlonly
-
-@section OCCT_OVW_SECTION_2 Copyrights
-
-Copyright(c) 2001-2013 by OPEN CASCADE S.A.S. All rights reserved.
-
- Trademark information
-----------------------
-
-You are hereby informed that all software is a property of its respective authors and is protected by
-international and domestic laws on intellectual property and trademarks.
-Should you need further information, please directly contact the authors.
-
-CAS.CADE and Open CASCADE are registered trademarks of OPEN CASCADE S.A.S.
-
- Acknowledgement
-------------------
-
-The following parties are acknowledged for producing tools which are used within
-Open CASCADE Technology libraries or for release preparation.
-
-You are hereby informed that all rights to the software listed below belong to its respective
-authors and such software may not be freely available and/or be free of charge for any kind
-of use or purpose. We strongly recommend that you carefully read the license of these products
-and, in case you need any further information, directly contact their authors.
-
-**Qt** is a cross-platform application framework that is widely used for developing application software
-with graphical user interface (GUI). Qt is free and open source software distributed under
-the terms of the GNU Lesser General Public License. In OCCT Qt is used for programming samples.
-If you need further information on Qt, please, refer to Qt Homepage (qt.digia.com).
-
-**Tcl** is a high-level programming language. Tk is a graphical user interface (GUI) toolkit,
-with buttons, menus, listboxes, scrollbars, and so on. Taken together Tcl and Tk provide a solution
-to develop cross-platform graphical user interfaces with a native look and feel. Tcl/Tk is under copyright by
-Scriptics Corp., Sun Microsystems, and other companies. However, Tcl/Tk is an open source, and
-the copyright allows you to use, modify, and redistribute Tcl/Tk for any purpose, without an
-explicit license agreement and without paying any license fees or royalties.
-To use Tcl/Tk, please refer to the Licensing Terms (http://www.tcl.tk/software/tcltk/license.html).
-
-**Robert Boehne** has developed **GNU Autoconf**, **Automake** and **Libtool** scripts and makefiles
-for the Open CASCADE project http://sourceforge.net/projects/autoopencas/,
-which became an initial groundwork for the build scripts based on respective GNU tools
-(autoconf, automake and libtool) in Open CASCADE Technology version 4.0.
-These scripts are now maintained by the OPEN CASCADE company.
-
-**GL2PS** is developed by Christophe Geuzaine and others. It is OpenGL to PostScript printing library.
-The library is licensed under GL2PS LICENSE http://www.geuz.org/gl2ps/COPYING.GL2PS Version 2, November 2003.
-
-**FreeType 2** is developed by Antoine Leca, David Turner, Werner Lemberg and others.
-It is a software font engine that is designed to be small, efficient, highly customizable and
-portable while capable of producing high-quality output (glyph images). This product
-can be used in graphic libraries, display servers, font conversion tools,
-text image generation tools, and many other products.
-
-FreeType 2 is released under two open-source licenses: BSD-like FreeType License and the GPL.
-
-**Intel(R) Threading Building Blocks (TBB)** offers a rich and complete approach to expressing parallelism in a C++ program.
-It is a library that helps you to take advantage of multi-core processor performance without having to be a threading expert.
-Threading Building Blocks is not just a threads-replacement library. It represents a higher-level, task-based parallelism that
-abstracts platform details and threading mechanisms for scalability and performance.
-TBB is available under GPLv2 license with the runtime exception.
-
-Open CASCADE Technology WOK module on Windows also makes use of LGPL-licensed C routines * regexp and getopt, taken from GNU C library.
-
-**Doxygen** (Copyright (c) 1997-2010 by Dimitri van Heesch) is open source documentation system for
-C++, C, Java, Objective-C, Python, IDL, PHP and C#. This product is used in Open CASCADE Technology
-for automatic creation of Technical Documentation from C++ header files.
-If you need further information on Doxygen, please refer to http://www.stack.nl/~dimitri/doxygen/index.html.
-
-**Graphviz** is open source graph visualization software developed by John Ellson, Emden Gansner, Yifan Hu and Arif Bilgin.
-Graph visualization is representiation of structured information as diagrams of abstract graphs and networks.
-This product is used together with Doxygen in Open CASCADE Technology for automatic creation of Technical Documentation
-(generation of dependency graphs). Current versions of Graphviz are licensed on an open source
-basis only under The Eclipse Public License (EPL) (http://www.graphviz.org/License.php).
-
-**Inno Setup** is a free script-driven installation system created in CodeGear Delphi by Jordan Russell.
-In OCCT Inno Setup is used to create Installation Wizard on Windows.
-It is licensed under Inno Setup License (http://www.jrsoftware.org/files/is/license.txt).
-
-**FreeImage** is an Open Source library supporting popular graphics image formats, such as PNG, BMP, JPEG, TIFF
-and others used by multimedia applications. This library is developed by Hervé Drolon and Floris van den Berg.
-FreeImage is easy to use, fast, multithreading safe, compatible with all 32-bit or 64-bit versions of Windows,
-and cross-platform (works both with Linux and Mac OS X). FreeImage is licensed under the
-GNU General Public License, version 2.0 (GPLv2) and
-the FreeImage Public License (FIPL) (http://freeimage.sourceforge.net/freeimage-license.txt).
-
-Adobe Systems, Inc. provides **Adobe Acrobat Professional**, which is a software to view, create, manipulate,
-print and manage files in Portable Document Format (PDF).
-This product is used in OCCT for the development and update of User's Guides.
-
-The same developer provides **Robohelp HTML** that allows developing online Help for applications that are run on the Web and on Intranets.
-**Robohelp HTML X5.0.2** is used in OCCT for the development and update of OCCT Overview.
-
-**Linux** is a registered trademark of Linus Torvalds.
-
-**Windows** is a registered trademark of Microsoft Corporation in the United States and other countries.
-
-**Mac** and the Mac logo are trademarks of Apple Inc., registered in the U.S. and other countries.
-
-
-@section OCCT_OVW_SECTION_3 Introduction
-
-
-This document is just an introduction to Open CASCADE Technology (OCCT) dealing with
-compatibility and installation issues and providing a general description of OCCT modules
-and other features. All modules and development tools are described in User's Guides, available in
-Adobe Portable Document Format (PDF). To read this format, you need Adobe Acrobat Reader,
-which is a freeware and can be downloaded from the Adobe site.
-All user guides can be accessed directly from this help.
-
-Alongside with PDF User Guides, OCCT suggests its users full reference documentation on all
-implementation classes automatically generated by Doxygen software.
-This Doxygen generated documentation is supplied in the form of a separate package,
-in a usual html file format.
-
-Reference documentation is presented in **Modules --> Toolkits --> Packages --> Classes**
-logic structure with cross-references to all OCCT classes and complete in-browser search by all classes.
-
-**Recommendation for generation of reference documentation**
-
-Reference documentation can be generated by OCCT binary WOK package that
-is available for downloading from www.opencascade.org and dev.opencascade.org sites.
-
-Prerequisites:
-
- * Doxygen version 1.7.4 or higher
- * Graphviz version 2.28.0 or higher
-
-Run WOK (cd \<WOK_INSTALL_DIR\>/site folder):
-
-* Using WOK TCL shell:
- > wok_tclsh.sh
-
-* Using Emacs editor:
- > wok_emacs.sh
-
-In the WOK prompt, step into your workbench:
-
- >wokcd <your workbench>
-
-In your workbench, use **wgendoc** command with –h argument to get information about arguments of **wgendoc** command:
-
- >wgendoc -h
-
-then run **wgendoc** command with required arguments
-
-e.g., wgendoc –output=d:/occt/doc {–m=Draw Visualization} -chm
-
-@section OCCT_OVW_SECTION_5 Requirements
-
-@subsection OCCT_OVW_SECTION_5_1 Linux Intel
-<table>
-<tr> <th>Operating System </th> <th> 64-bit: Mandriva 2010, CentOS 5. 5, CentOS 6.3, Fedora 17, Fedora 18, Ubuntu-1304, Debian 6.0 * </th> </tr>
-<tr> <td> Minimum memory </td> <td> 512 Mb, 1 Gb recommended </td > </tr>
-<tr> <td> Free disk space (complete installation) </td> <td> For full installation Open CASCADE Technology requires 600 Mb of disk space. </td > </tr>
-<tr> <td>Minimum swap space </td> <td> 500 Mb </td > </tr>
-<tr> <td> Video card </td> <td> **GeForce** The following versions of GeForce drivers are recommended: 64-bit Version: 100.14.19 or later http://www.nvidia.com/object/linux_display_amd64_100.14.19.html 32-bit Version: 100.14.19 or later http://www.nvidia.com/object/linux_display_ia32_100.14.19.html </td > </tr>
-<tr> <td> Graphic library </td> <td> OpenGL 1.1+ (OpenGL 1.5+ is recommended) </td > </tr>
-<tr> <td>C++ </td> <td>GNU gcc 4.0. - 4.7.3. </td > </tr>
-<tr> <td> TCL (for testing tools) </td> <td> Tcltk 8.5 or 8.6 http://www.tcl.tk/software/tcltk/8.6.html</td > </tr>
-<tr> <td> Qt (for demonstration tools) </td> <td> Qt 4.6.2 http://qt.nokia.com/downloads </td > </tr>
-<tr> <td> Freetype (OCCT Text rendering) </td> <td> freetype-2.4.11 http://sourceforge.net/projects/freetype/files/ </td > </tr>
-<tr> <td> FreeImage (Support of common graphic formats) </td> <td>FreeImage 3.15.4 http://sourceforge.net/projects/freeimage/files/Source%20Distribution/ </td > </tr>
-<tr> <td> gl2ps (Export contents of OCCT viewer to vector graphic file) </td> <td> gl2ps-1.3.8 http://geuz.org/gl2ps/ </td > </tr>
-<tr> <td>TBB (optional tool for parallelized version of BRepMesh component) </td> <td> TBB 3.x or 4.x http://www.threadingbuildingblocks.org/ </td > </tr>
-<tr> <td> OpenCL (optional for providing ray tracing visualization core </td> <td>http://developer.amd.com/tools-and-sdks/heterogeneous-computing/amd-accelerated-parallel-processing-app-sdk/downloads/ </td> </tr>
-</table>
-\* Debian 60 64 bit is a permanently tested platform.
-
-@subsection OCCT_OVW_SECTION_5_2 Windows Intel
-
-<table>
-<tr> <th>Operating System </th> <th> 32/64-bit: 8/ 7 SP1 / VISTA SP2 /XP SP3 </th> </tr>
-<tr> <td> Minimum memory </td> <td> 512 Mb, 1 Gb recommended </td > </tr>
-<tr> <td> Free disk space (complete installation) </td> <td> For full installation Open CASCADE Technology requires 650 Mb of disk space but during the process of installation you will need 1,2 Gb of free disk space. </td > </tr>
-<tr> <td>Minimum swap space </td> <td> 500 Mb </td > </tr>
-<tr> <td> Video card </td> <td> **GeForce** Version 266.58 WHQL or later is recommended: http://www.nvidia.com/Download/index.aspx
- </td > </tr>
-<tr> <td> Graphic library </td> <td> OpenGL 1.1+ (OpenGL 1.5+ is recommended) </td > </tr>
-<tr> <td>C++ </td> <td>Microsoft Visual Studio .NET 2005 SP1 with all security updates
-Microsoft Visual Studio .NET 2008 SP1*
-Microsoft Visual Studio .NET 2010
-Microsoft Visual Studio .NET 2012
-Microsoft Visual Studio .NET 2013
- </td > </tr>
-<tr> <td> TCL (for testing tools) </td> <td> TActiveTcl 8.5 or 8.6
-http://www.activestate.com/activetcl/downloads </td > </tr>
-<tr> <td> Qt (for demonstration tools) </td> <td> Qt 4.6.2 http://qt.digia.com/downloads </td > </tr>
-<tr> <td> Freetype (OCCT Text rendering) </td> <td> freetype-2.4.11 http://sourceforge.net/projects/freetype/files/ </td > </tr>
-<tr> <td> FreeImage (Support of common graphic formats )</td> <td>FreeImage 3.15.4 http://sourceforge.net/projects/freeimage/files/Source%20Distribution/ </td > </tr>
-<tr> <td> gl2ps (Export contents of OCCT viewer to vector graphic file) </td> <td> gl2ps-1.3.8 http://geuz.org/gl2ps/ </td > </tr>
-<tr> <td>TBB (optional tool for parallelized version of BRepMesh component) </td> <td> TBB 3.x or 4.x http://www.threadingbuildingblocks.org/ </td > </tr>
-<tr> <td> OpenCL (optional for providing ray tracing visualization core </td> <td>http://developer.amd.com/tools-and-sdks/heterogeneous-computing/amd-accelerated-parallel-processing-app-sdk/downloads/ </td> </tr>
-</table>
-
-* The official release of OCCT for Windows contains libraries built with VC++ 2008.
-
-
-@subsection OCCT_OVW_SECTION_5_3 MAC OS X
-
-<table>
-<tr> <th>Operating System </th> <th> Mac OS X 10.6.8 Snow Leopard / 10.7 Lion </th> </tr>
-<tr> <td> Minimum memory </td> <td> 512 Mb, 1 Gb recommended </td > </tr>
-<tr> <td> Free disk space (complete installation) </td> <td> For full installation Open CASCADE Technology requires 600 Mb of disk space. </td > </tr>
-<tr> <td>Minimum swap space </td> <td> 500 Mb </td > </tr>
-<tr> <td> Video card </td> <td> **GeForce** Version 266.58 WHQL or later is recommended: http://www.nvidia.com/Download/index.aspx
- </td > </tr>
-<tr> <td> Graphic library </td> <td> OpenGL 1.1+ (OpenGL 1.5+ is recommended) </td > </tr>
-<tr> <td>C++ </td> <td>XCode 3.2 or newer (4.x is recommended) </td > </tr>
-<tr> <td> Qt (for demonstration tools) </td> <td> Qt 4.6.2 http://qt.digia.com/downloads </td > </tr>
-<tr> <td> Freetype (OCCT Text rendering) </td> <td> freetype-2.4.11 http://sourceforge.net/projects/freetype/files/ </td > </tr>
-<tr> <td> FreeImage (Support of common graphic formats )</td> <td>FreeImage 3.15.4 http://sourceforge.net/projects/freeimage/files/Source%20Distribution/ </td > </tr>
-<tr> <td> gl2ps (Export contents of OCCT viewer to vector graphic file) </td> <td> gl2ps-1.3.8 http://geuz.org/gl2ps/ </td > </tr>
-<tr> <td>TBB (optional tool for parallelized version of BRepMesh component) </td> <td> TBB 3.x or 4.x http://www.threadingbuildingblocks.org/ </td > </tr>
-<tr> <td> OpenCL (optional for providing ray tracing visualization core </td> <td> OpenCL 1.2.8 native </td> </tr>
-</table>
-
-@section OCCT_OVW_SECTION_4 Installation
-
-Open CASCADE Technology can be installed with binaries precompiled by
-Visual C++ 2008 using Installation Procedure under Windows platform only
-
-The source package and the building tools are available for self-dependent
-preparation binary files on Unix and Windows platforms.
-
-@subsection OCCT_OVW_SECTION_4_1 Windows
-
-**Recommendation:**
-
-If you have a previous version of OCCT installed on your station,
-and you do not plan to use it along with the new version, you might want to uninstall
-the previous version (using Control Panel, Add/Remove Programs) before
-the installation of this new version, to avoid possible problems
-(conflict of system variables, paths, etc).
-
-**Attention:** For full installation OCCT requires approximately 650 Mb of disk space,
-but during the installation process you will need 1,2 Gb of free disk space.
-
-OCCT installation with reference documentation requires 1,4 Gb on disk.
-
- * Download the OCCT installer from OPEN CASCADE web site using the link. you have been provided
- * Launch the installer and follow the instructions.
-
-### Third-party tools
-
-
-The includes and binaries of third-party libraries necessary for building and launching
-OCCT are included into binary distribution (built with Visual C++ 2008).
-To recompile OCCT libraries with other Visual C++ versions,
-it is necessary to install headers and libraries of these third-party products.
-
-The recommended way to do this is to download each of the third-party tools from its web site
-and build it using the relevant tools. For additional convenience of the users,
-OPEN CASCADE also provides the documents with recommendations on building
-third-party products from source files.
-
-
-
-When the installation is complete, you will find the following directories
-(some might be absent in case of custom installation):
-
-@image html /overview/images/overview_installation.png "The directory tree"
-@image latex /overview/images/overview_installation.png "The directory tree"
-
-
-
- * **adm** This folder contains administration files, which allow rebuilding OCCT;
- * **adm/cmake** This folder contains files of CMake building procedure;
- * **adm/msvc** This folder contains Visual Studio projects for Visual C++ 2005, 2008 and 2010, which allow rebuilding OCCT under Windows platform in 32 and 64-bit mode;
- * **data** This folder contains CAD files in different formats, which can be used to test the OCCT functionalities;
- * **doc** This folder contains OCCT Overview documentation;
- * **drv** This folder contains source files generated by WOK (private header files and instantiations of generic classes);
- * **inc** This folder contains all OCCT header files;
- * **samples** This folder contains sample applications.
- * **src** This folder contains OCCT source files. They are organized in folders, one per development unit;
- * **tests** This folder contains scripts for OCCT testing.
- * **win32/vc9** This folder contains executable and library files built in optimize mode for Windows platform by Visual C++ 2008;
-
-3rd party products have been moved to the root of Open CASCADE installation.
-
-@image html /overview/images/overview_3rdparty.png "The third-party products"
-@image latex /overview/images/overview_3rdparty.png "The third-party products"
-
-
-@subsection OCCT_OVW_SECTION_4_2 System Environment Variables
-
-To run any Open CASCADE Technology application you need to set the environment variables.
-
-### On Windows
-
-
-You can define the environment variables with env.bat script located in the
-OpenCACADE<version_number>/ros folder. This script accepts two arguments to be used:
-the version of Visual Studio (vc8, vc9, or vc10) and the architecture (win32 or win64).
-
-The additional environment settings necessary for compiling OCCT libraries and samples
-by Microsoft Visual Studio can be set using script custom.bat located in the same folder.
-You might need to edit this script to correct the paths to third-party libraries
-if they are installed on your system in a non-default location.
-
-Script msvc.bat can be used with the same arguments for immediate launch of Visual Studio for (re)compiling OCCT.
-
-### On Unix
-
-
- If OCCT was built by Code::Blocks, you can define the environment variables with env_cbp.sh or custom_cbp.sh script.
-
- If OCCT was built by Automake, you can define the environment variables with env_amk.sh or custom_amk.sh script.
-
-The scripts are located in the OpenCACADE<version_number>/ros folder of the source package.
-
-
-### Description of system variables:
-
-
- * **CASROOT** is used to define the root directory of Open CASCADE Technology;
- * **PATH** is required to define the path to OCCT binaries and 3rdparty folder;
- * **LD_LIBRARY_PATH** is required to define the path to OCCT libraries (on UNIX platforms only);
- * **MMGT_OPT** if set to 1, the memory manager performs optimizations as described below; if set to 2,
- Intel (R) TBB optimized memory manager is used; if 0 (default), every memory block is allocated
- in C memory heap directly (via malloc() and free() functions).
- In the latter case, all other options except MMGT_CLEAR and MMGT_REENTRANT are ignored;
- * **MMGT_CLEAR** if set to 1 (default), every allocated memory block is cleared by zeros;
- if set to 0, memory block is returned as it is;
- * **MMGT_CELLSIZE** defines the maximal size of blocks allocated in large pools of memory. Default is 200;
- * **MMGT_NBPAGES** defines the size of memory chunks allocated for small blocks in pages
- (operating-system dependent). Default is 10000;
- * **MMGT_THRESHOLD** defines the maximal size of blocks that are recycled internally
- instead of being returned to the heap. Default is 40000;
- * **MMGT_MMAP** when set to 1 (default), large memory blocks are allocated using
- memory mapping functions of the operating system; if set to 0,
- they will be allocated in the C heap by malloc();
- * **MMGT_REENTRANT** when set to 1 (default), all calls to the
- optimized memory manager will be secured against possible simultaneous access from different execution threads.
-
-This variable should be set in any multithreaded application that uses
-an optimized memory manager (MMGT_OPT=1) and has more than one thread
-potentially calling OCCT functions. If set to 0, OCCT memory management and
-exception handling routines will skip the code protecting from possible concurrency
-in multi-threaded environment. This can yield some performance gain in some applications,
-but can lead to unpredictable results if used in a multithreaded application;
-
-**Special note:** for applications that use OCCT memory manager from more than one thread,
-on multiprocessor hardware, it is recommended to use options MMGT_OPT=2 and MMGT_REENTRANT=1.
-
- * **CSF_LANGUAGE** is required to define the default language of messages;
- * **CSF_EXCEPTION_PROMPT** – if defined and set to 1 then a diagnostic message is displayed in case of an exception;
- * **CSF_MDTVFontDirectory** accesses the fonts that can be used in OCCT;
- * **CSF_MDTVTexturesDirectory** defines the directory for available textures when using texture mapping;
- * **CSF_UnitsDefinition** and **CSF_UnitsLexicon** are required by programs considering units;
- * **CSF_SHMessage** is required in order to define the path to the messages file for *ShapeHealing*;
- * **CSF_XSMessage** is required in order to define the path to the messages file for **STEP** and **IGES** translators;
- * **CSF_StandardDefaults** and **CSF_PluginDefaults** are required in order to maintain CASCADE Persistence mechanism to make possible any open/save operations with OCAF documents;
- * **CSF_StandardLiteDefaults** is required in order to maintain *OCCT Persistence mechanism* to make possible any open/save operations with Lite OCAF documents;
- * **CSF_XCAFDefaults** any open/save operations for **XDE** documents;
- * **CSF_GraphicShr** is required to define the path to the *TKOpenGl* library;
- * **CSF_IGESDefaults** and **CSF_STEPDefaults** are required for **IGES** and **STEP** translators correspondingly in order to define the path to the resource files;
- * **CSF_XmlOcafResource** is required in order to set the path to **XSD** resources, which defines XML grammar.
-
-As part of XML persistence support, these definitions can be used by end users
-in XML validators or editors, together with persistent XmlOcaf documents;
-
-* **CSF_MIGRATION_TYPES** is required in order to read documents that contain old data types, such as *TDataStd_Shape*;
-* **TCLLIBPATH**, **TCL_LIBRARY**, **TK_LIBRARY** and **TIX_LIBRARY** are required to allow work with **DRAW** and **WOK**.
-
-@section OCCT_OVW_SECTION_6 Release Notes
-
-
-Open CASCADE Technology latest version
-@htmlonly
-<a href="http://occtrel.nnov.opencascade.com/OpenCASCADE6.7.0/doc/release_notes.pdf">Release Notes</a>
-@endhtmlonly (PDF)
-
-
-@section OCCT_OVW_SECTION_7 Getting Started
-
-
-@subsection OCCT_OVW_SECTION_7_1 Draw Test Harness
-
-Draw is a command interpreter based on TCL and a graphical system used for testing and demonstrating OCCT modeling libraries.
-
-Draw can be used interactively to create, display and modify objects such as curves, surfaces and topological shapes.
-
-@image html /overview/images/overview_draw.png
-@image latex /overview/images/overview_draw.png
-
-Scripts can be written to customize Draw and perform tests.
-New types of objects and new commands can be added using C++ programming language.
-
-Draw contains:
-
- * A command interpreter based on TCL command language.
- * A 2D an 3D graphic viewer with support of operations such as zoom, pan, rotation and full-screen views.
- * An optional set of geometric commands to create and modify curves and surfaces and to use OCCT geometry algorithms.
- * A set of topological commands to create and modify BRep shapes and to use OCCT topology algorithms.
- * A set of graphic commands for view and display operations including Mesh Visualization Service.
- * A set of Application framework commands for handling of files and attributes.
- * A set of Data Exchange commands for translation of files from various formats (IGES,STEP) into OCCT shapes.
- * A set of Shape Healing commands: check of overlapping edges, approximation of a shape to BSpline, etc.
-
-You can add new custom test harness commands to Draw in order to test
-or demonstrate a new functionality, which you are developing.
-
-Currently DRAW Test Harness is a single executable called DRAWEXE.
-
-Commands grouped in toolkits can be loaded at run-time thereby implementing dynamically loaded plug-ins.
-Thus you can work only with the commands that suit your needs adding
-the commands dynamically without leaving the Test Harness session.
-
-Declaration of available plug-ins is done through 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.
-
-The whole process of using the plug-in mechanism as well as the instructions for extending Test Harness is described in the
-@htmlonly
-<a href="http://occtrel.nnov.opencascade.com/OpenCASCADE6.6.0/doc/OCCT_Tests.pdf">User's Guide/</a>
-@endhtmlonly
-
-Draw Test Harness provides an environment for OCCT automated testing system. Please, consult its
-@htmlonly
-<a href="http://occtrel.nnov.opencascade.com/OpenCASCADE6.6.0/doc/OCCT_Tests.pdf">User's Guide /</a>
-@endhtmlonly
-for details.
-
-Remarks:
-
-* The DRAWEXE executable is delivered with the installation procedure on Windows platform only.
-* To start it, launch DRAWEXE executable from Open CASCADE Technology//Draw Test Harness item of the Start\\Programs menu.
-
-@subsection OCCT_OVW_SECTION_7_2 Experimenting with Draw Test Harness
-
- Running Draw
-------------
-
-**On Linux:**
-
-1. If OCCT was built by Code::Blocks * use $CASROOT/draw_cbp.sh file to launch DRAWEXE executable;
-2. If OCCT was built by Automake * use $CASROOT/draw_amk.sh file to launch DRAWEXE executable;
-
-Draw[1]> prompt appears in the command window
-
-Type pload ALL
-
-**On Windows:**
-
-Launch Draw executable from Open CASCADE Technology\\Test Harness\\Draw Test Harness
-item of the Start\\Programs menu or Use $CASROOT\\draw.bat file to launch DRAWEXE executable.
-
-Draw[1]> prompt appears in the command window
-
-Type pload ALL
-
-**Creating your first geometric objects**
-
-1. In the command window, type axo to create an axonometric view
-2. Type box b -10 -10 -10 20 20 20 to create a cube b of size 20,
- parallel to the X Y Z axis and centered on the origin.
- The cube will be displayed in the axonometric view in wireframe mode
-3. Type fit to fill the viewer with the cube
-4. Type pcylinder c 2 30 to create a cylinder c of radius 2 and height 30.
- The cylinder will be displayed in addition to the cube
-
-**Manipulating the view**
-
-1. Type clear to erase the view
-2. Type donly c to display the cylinder only
-3. Type donly b to display the cube only
-4. Type hlr hlr b to display the cube in the hidden line removal mode
-
-**Running demonstration files**
-
-1. Type cd ..//.. to return to the root directory
-2. Type cd src//DrawResources to reach the DrawResources directory
-3. Type source "Available Demo File" to run the demonstration provided with Open CASCADE
-4. The following demonstration files are available:
- * DataExchangeDemo.tcl
- * ModelingDemo.tcl
- * OCAFDemo.tcl
- * VisualizationDemo.tcl
-
-**Getting Help**
-
-1. Type help to see all available commands
-2. Type help command-name to find out the arguments for a given command
-
-@subsection OCCT_OVW_SECTION_7_3 Programming Samples
-
-@subsubsection OCCT_OVW_SECTION_7_3_1 MFC
-
-Visual C++ programming samples containing 10 Visual C++ projects
-illustrating how to use a particular module or functionality.
-
-The list of MFC samples:
-
- * Geometry
- * Modeling
- * Viewer2d
- * Viewer3d
- * ImportExport
- * Ocaf
- * Triangulation
- * HLR
- * Animation
- * Convert
-
-@image html /overview/images/overview_mvc.png
-@image latex /overview/images/overview_mvc.png
-
-**Remarks:**
-
- * MFC samples are available only on Windows platform;
- * To start a sample use Open CASCADE Technology\\Samples\\Mfc\\ item of the Start\\Programs menu;
- * Read carefully readme.txt to learn about launching and compilation options.
-
-@subsubsection OCCT_OVW_SECTION_7_3_2 Qt
-
-OCCT contains three samples based on Qt application framework
-
- Import Export
--------------
-
- Import Export programming sample contains 3D Viewer and Import // Export functionality.
-
-@image html /overview/images/overview_qt.png
-@image latex /overview/images/overview_qt.png
-
- Tutorial
----------
-
-The Qt programming tutorial teaches how to use Open CASCADE Technology services to model a 3D object.
-The purpose of the tutorial is not to explain all OCCT classes but
-to help start thinking in terms of the Open CASCADE Technology.
-
-This tutorial assumes that the user has experience in using and setting up C++.
-From the viewpoint of programming, Open CASCADE Technology is designed
-to enhance user's C++ tools with high performance modeling classes, methods and functions.
-The combination of these resources allows creating substantial applications.
-
-**See also:** @subpage overview__tutorial "3D Object Tutorial"
-
- Voxel
-------
-
-This is a demonstration application showing OCCT voxel models.
-It also includes a set of non-regression tests and other commands
-for testing this functionality (accessible only through TEST pre-processor definition).
-
-**See also:**
- @htmlonly
-<a href="http://occtrel.nnov.opencascade.com/OpenCASCADE6.6.0/doc/voxels_wp.pdf">Voxels User's guide (PDF)</a>
-@endhtmlonly
-
-**Remarks:**
-
- * Qt samples are available on all supported platforms;
- * To start a sample on Windows use Open CASCADE Technology\\Samples\\Qt\\ item of the Start\\Programs menu.
-
-@subsubsection OCCT_OVW_SECTION_7_3_3 C#
-
-C# sample containing 3D Viewer and Import // Export functionality.
-
-@image html /overview/images/overview_c__ie.png
-@image latex /overview/images/overview_c__ie.png
-
-Import:
-
- * BRep
- * Iges
- * Step
-
-Export:
-
- * Brep
- * Iges
- * Step
- * Stl
- * Vrml
-
-**Remarks:**
-
- * C# sample is available only on Windows platform;
- * It is delivered in source code only and must be built with Microsoft Visual C++ 2005.
-
-
-
-
+++ /dev/null
- Tutorial {#overview__tutorial}
-=======
-
-@section sec1 Overview
-
-
-This tutorial will teach you how to use Open CASCADE Technology services to model a 3D object. The purpose of this tutorial is not to describe all Open CASCADE Technology classes but to help you start thinking in terms of Open CASCADE Technology as a tool.
-
-
-@subsection OCCT_TUTORIAL_SUB1_1 Prerequisites
-
-This tutorial assumes that you have experience in using and setting up C++.
-From a programming standpoint, Open CASCADE Technology is designed to enhance your C++ tools with 3D modeling classes, methods and functions. The combination of all these resources will allow you to create substantial applications.
-
-@subsection OCCT_TUTORIAL_SUB1_2 The Model
-
-To illustrate the use of classes provided in the 3D geometric modeling toolkits, you will create a bottle as shown:
-
-@image html /overview/tutorial/images/tutorial_image001.png
-@image latex /overview/tutorial/images/tutorial_image001.png
-
-In the tutorial we will create, step-by-step, a function that will model a bottle as shown above. You will find the complete source code of this tutorial, including the very function *MakeBottle* in the distribution of Open CASCADE Technology. The function body is provided in the file samples/qt/Tutorial/src/MakeBottle.cxx.
-
-@subsection OCCT_TUTORIAL_SUB1_3 Model Specifications
-
-We first define the bottle specifications as follows:
-
-| Object Parameter | Parameter Name | Parameter Value |
-| :--------------: | :------------: | :-------------: |
-| Bottle height | MyHeight | 70mm |
-| Bottle width | MyWidth | 50mm |
-| Bottle thickness | MyThickness | 30mm |
-
-In addition, we decide that the bottle's profile (base) will be centered on the origin of the global Cartesian coordinate system.
-
-@image html /overview/tutorial/images/tutorial_image002.png
-@image latex /overview/tutorial/images/tutorial_image002.png
-
-This modeling requires four steps:
-
- * build the bottle's Profile
- * build the bottle's Body
- * build the Threading on the bottle's neck
- * build the result compound
-
-
-@section sec2 Building the Profile
-
-@subsection OCCT_TUTORIAL_SUB2_1 Defining Support Points
-
-To create the bottle's profile, you first create characteristic points with their coordinates as shown below in the (XOY) plane. These points will be the supports that define the geometry of the profile.
-
-@image html /overview/tutorial/images/tutorial_image003.png
-@image latex /overview/tutorial/images/tutorial_image003.png
-
-There are two classes to describe a 3D Cartesian point from its X, Y and Z coordinates in Open CASCADE Technology:
-
- * the primitive geometric *gp_Pnt* class
- * the transient *Geom_CartesianPoint* class manipulated by handle
-
-A handle is a type of smart pointer that provides automatic memory management.
-To choose the best class for this application, consider the following:
-
- * *gp_Pnt* is manipulated by value. Like all objects of its kind, it will have a limited lifetime.
- * *Geom_CartesianPoint* is manipulated by handle and may have multiple references and a long lifetime.
-
-Since all the points you will define are only used to create the profile's curves, an object with a limited lifetime will do. Choose the *gp_Pnt* class.
-To instantiate a *gp_Pnt* object, just specify the X, Y, and Z coordinates of the points in the global cartesian coordinate system:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Pnt aPnt1(-myWidth / 2., 0, 0);
- gp_Pnt aPnt2(-myWidth / 2., -myThickness / 4., 0);
- gp_Pnt aPnt3(0, -myThickness / 2., 0);
- gp_Pnt aPnt4(myWidth / 2., -myThickness / 4., 0);
- gp_Pnt aPnt5(myWidth / 2., 0, 0);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Once your objects are instantiated, you can use methods provided by the class to access and modify its data. For example, to get the X coordinate of a point:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
-Standard_Real xValue1 = aPnt1.X();
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-@subsection OCCT_TUTORIAL_SUB2_2 Profile: Defining the Geometry
-With the help of the previously defined points, you can compute a part of the bottle's profile geometry. As shown in the figure below, it will consist of two segments and one arc.
-
-@image html /overview/tutorial/images/tutorial_image004.png
-@image latex /overview/tutorial/images/tutorial_image004.png
-
-To create such entities, you need a specific data structure, which implements 3D geometric objects. This can be found in the Geom package of Open CASCADE Technology.
-In Open CASCADE Technology a package is a group of classes providing related functionality. The classes have names that start with the name of a package they belong to. For example, *Geom_Line* and *Geom_Circle* classes belong to the *Geom* package. The *Geom* package implements 3D geometric objects: elementary curves and surfaces are provided as well as more complex ones (such as *Bezier* and *BSpline*).
-However, the *Geom* package provides only the data structure of geometric entities. You can directly instantiate classes belonging to *Geom*, but it is easier to compute elementary curves and surfaces by using the *GC* package.
-This is because the *GC* provides two algorithm classes which are exactly what is required for our profile:
-
- * Class *GC_MakeSegment* to create a segment. One of its constructors allows you to define a segment by two end points P1 and P2
- * Class *GC_MakeArcOfCircle* to create an arc of a circle. A useful constructor creates an arc from two end points P1 and P3 and going through P2.
-
-Both of these classes return a *Geom_TrimmedCurve* manipulated by handle. This entity represents a base curve (line or circle, in our case), limited between two of its parameter values. For example, circle C is parameterized between 0 and 2PI. If you need to create a quarter of a circle, you create a *Geom_TrimmedCurve* on C limited between 0 and M_PI/2.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- Handle(Geom_TrimmedCurve) aArcOfCircle = GC_MakeArcOfCircle(aPnt2,aPnt3,aPnt4);
- Handle(Geom_TrimmedCurve) aSegment1 = GC_MakeSegment(aPnt1, aPnt2);
- Handle(Geom_TrimmedCurve) aSegment2 = GC_MakeSegment(aPnt4, aPnt5);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-All *GC* classes provide a casting method to obtain a result automatically with a function-like call. Note that this method will raise an exception if construction has failed. To handle possible errors more explicitly, you may use the *IsDone* and *Value* methods. For example:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- GC_MakeSegment mkSeg (aPnt1, aPnt2);
- Handle(Geom_TrimmedCurve) aSegment1;
- if(mkSegment.IsDone()){
- aSegment1 = mkSeg.Value();
- }
- else {
- // handle error
- }
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB2_3 Profile: Defining the Topology
-
-
-You have created the support geometry of one part of the profile but these curves are independent with no relations between each other.
-To simplify the modeling, it would be right to manipulate these three curves as a single entity.
-This can be done by using the topological data structure of Open CASCADE Technology defined in the *TopoDS* package: it defines relationships between geometric entities which can be linked together to represent complex shapes.
-Each object of the *TopoDS* package, inheriting from the *TopoDS_Shape* class, describes a topological shape as described below:
-
-| Shape | Open CASCADE Technology Class | Description |
-| :-------- | :---------------------------- | :------------------------------------------------------------ |
-| Vertex | TopoDS_Vertex | Zero dimensional shape corresponding to a point in geometry. |
-| Edge | TopoDS_Edge | One-dimensional shape corresponding to a curve and bounded by a vertex at each extremity.|
-| Wire | TopoDS_Wire | Sequence of edges connected by vertices. |
-| Face | TopoDS_Face | Part of a surface bounded by a closed wire(s). |
-| Shell | TopoDS_Shell | Set of faces connected by edges. |
-| Solid | TopoDS_Solid | Part of 3D space bounded by Shells. |
-| CompSolid | TopoDS_CompSolid | Set of solids connected by their faces. |
-| Compound | TopoDS_Compound | Set of any other shapes described above. |
-
-Referring to the previous table, to build the profile, you will create:
-
- * Three edges out of the previously computed curves.
- * One wire with these edges.
-
-@image html /overview/tutorial/images/tutorial_image005.png
-@image latex /overview/tutorial/images/tutorial_image005.png
-
-However, the *TopoDS* package provides only the data structure of the topological entities. Algorithm classes available to compute standard topological objects can be found in the *BRepBuilderAPI* package.
-To create an edge, you use the BRepBuilderAPI_MakeEdge class with the previously computed curves:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Edge aEdge1 = BRepBuilderAPI_MakeEdge(aSegment1);
- TopoDS_Edge aEdge2 = BRepBuilderAPI_MakeEdge(aArcOfCircle);
- TopoDS_Edge aEdge3 = BRepBuilderAPI_MakeEdge(aSegment2);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-In Open CASCADE Technology, you can create edges in several ways. One possibility is to create an edge directly from two points, in which case the underlying geometry of this edge is a line, bounded by two vertices being automatically computed from the two input points. For example, aEdge1 and aEdge3 could have been computed in a simpler way:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Edge aEdge1 = BRepBuilderAPI_MakeEdge(aPnt1, aPnt3);
- TopoDS_Edge aEdge2 = BRepBuilderAPI_MakeEdge(aPnt4, aPnt5);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-To connect the edges, you need to create a wire with the *BRepBuilderAPI_MakeWire* class. There are two ways of building a wire with this class:
-
- * directly from one to four edges
- * by adding other wire(s) or edge(s) to an existing wire (this is explained later in this tutorial)
-
-When building a wire from less than four edges, as in the present case, you can use the constructor directly as follows:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Wire aWire = BRepBuilderAPI_MakeWire(aEdge1, aEdge2, aEdge3);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB2_4 Profile: Completing the Profile
-
-
-Once the first part of your wire is created you need to compute the complete profile. A simple way to do this is to:
-
- * compute a new wire by reflecting the existing one.
- * add the reflected wire to the initial one.
-
-@image html /overview/tutorial/images/tutorial_image006.png
-@image latex /overview/tutorial/images/tutorial_image006.png
-
-To apply a transformation on shapes (including wires), you first need to define the properties of a 3D geometric transformation by using the gp_Trsf class. This transformation can be a translation, a rotation, a scale, a reflection, or a combination of these.
-In our case, we need to define a reflection with respect to the X axis of the global coordinate system. An axis, defined with the gp_Ax1 class, is built out of a point and has a direction (3D unitary vector). There are two ways to define this axis.
-The first way is to define it from scratch, using its geometric definition:
-
- * X axis is located at (0, 0, 0) - use the *gp_Pnt* class.
- * X axis direction is (1, 0, 0) - use the *gp_Dir* class. A *gp_Dir* instance is created out of its X, Y and Z coordinates.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Pnt aOrigin(0, 0, 0);
- gp_Dir xDir(1, 0, 0);
- gp_Ax1 xAxis(aOrigin, xDir);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The second and simplest way is to use the geometric constants defined in the gp package (origin, main directions and axis of the global coordinate system). To get the X axis, just call the *gp::OX* method:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Ax1 xAxis = gp::OX();
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-As previously explained, the 3D geometric transformation is defined with the *gp_Trsf* class. There are two different ways to use this class:
-
- * by defining a transformation matrix by all its values
- * by using the appropriate methods corresponding to the required transformation (SetTranslation for a translation, SetMirror for a reflection, etc.): the matrix is automatically computed.
-
-Since the simplest approach is always the best one, you should use the SetMirror method with the axis as the center of symmetry.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Trsf aTrsf;
- aTrsf.SetMirror(xAxis);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-You now have all necessary data to apply the transformation with the BRepBuilderAPI_Transform class by specifying:
-
- * the shape on which the transformation must be applied.
- * the geometric transformation
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- BRepBuilderAPI_Transform aBRepTrsf(aWire, aTrsf);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-*BRepBuilderAPI_Transform* does not modify the nature of the shape: the result of the reflected wire remains a wire. But the function-like call or the *BRepBuilderAPI_Transform::Shape* method returns a *TopoDS_Shape* object:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Shape aMirroredShape = aBRepTrsf.Shape();
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-What you need is a method to consider the resulting reflected shape as a wire. The *TopoDS* global functions provide this kind of service by casting a shape into its real type. To cast the transformed wire, use the *TopoDS::Wire* method.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Wire aMirroredWire = TopoDS::Wire(aMirroredShape);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The bottle's profile is almost finished. You have created two wires: *aWire* and *aMirroredWire*. You need to concatenate them to compute a single shape. To do this, you use the *BRepBuilderAPI_MakeWire* class as follows:
-
- * create an instance of *BRepBuilderAPI_MakeWire*.
- * add all edges of the two wires by using the *Add* method on this object.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- BRepBuilderAPI_MakeWire mkWire;
- mkWire.Add(aWire);
- mkWire.Add(aMirroredWire);
- TopoDS_Wire myWireProfile = mkWire.Wire();
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@section sec3 Building the Body
-
-
-@subsection OCCT_TUTORIAL_SUB3_1 Prism the Profile
-
-
-To compute the main body of the bottle, you need to create a solid shape. The simplest way is to use the previously created profile and to sweep it along a direction. The *Prism* functionality of Open CASCADE Technology is the most appropriate for that task. It accepts a shape and a direction as input and generates a new shape according to the following rules:
-
-| Shape | Generates |
-| :----- | :----------------- |
-| Vertex | Edge |
-| Edge | Face |
-| Wire | Shell |
-| Face | Solid |
-| Shell | Compound of Solids |
-
-@image html /overview/tutorial/images/tutorial_image007.png
-@image latex /overview/tutorial/images/tutorial_image007.png
-
-Your current profile is a wire. Referring to the Shape/Generates table, you need to compute a face out of its wire to generate a solid.
-To create a face, use the *BRepBuilderAPI_MakeFace* class. As previously explained, a face is a part of a surface bounded by a closed wire. Generally, *BRepBuilderAPI_MakeFace* computes a face out of a surface and one or more wires.
-When the wire lies on a plane, the surface is automatically computed.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Face myFaceProfile = BRepBuilderAPI_MakeFace(myWireProfile);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The *BRepPrimAPI* package provides all the classes to create topological primitive constructions: boxes, cones, cylinders, spheres, etc. Among them is the *BRepPrimAPI_MakePrism* class. As specified above, the prism is defined by:
-
- * the basis shape to sweep;
- * a vector for a finite prism or a direction for finite and infinite prisms.
-
-You want the solid to be finite, swept along the Z axis and to be myHeight height. The vector, defined with the *gp_Vec* class on its X, Y and Z coordinates, is:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Vec aPrismVec(0, 0, myHeight);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-All the necessary data to create the main body of your bottle is now available. Just apply the *BRepPrimAPI_MakePrism* class to compute the solid:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Shape myBody = BRepPrimAPI_MakePrism(myFaceProfile, aPrismVec);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB3_2 Applying Fillets
-
-
-The edges of the bottle's body are very sharp. To replace them by rounded faces, you use the *Fillet* functionality of Open CASCADE Technology.
-For our purposes, we will specify that fillets must be:
-
- * applied on all edges of the shape
- * have a radius of *myThickness* / 12
-
-@image html /overview/tutorial/images/tutorial_image008.png
-@image latex /overview/tutorial/images/tutorial_image008.png
-
-To apply fillets on the edges of a shape, you use the *BRepFilletAPI_MakeFillet* class. This class is normally used as follows:
-
- * Specify the shape to be filleted in the *BRepFilletAPI_MakeFillet* constructor.
- * Add the fillet descriptions (an edge and a radius) using the *Add* method (you can add as many edges as you need).
- * Ask for the resulting filleted shape with the *Shape* method.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
-BRepFilletAPI_MakeFillet mkFillet(myBody);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-To add the fillet description, you need to know the edges belonging to your shape. The best solution is to explore your solid to retrieve its edges. This kind of functionality is provided with the *TopExp_Explorer* class, which explores the data structure described in a *TopoDS_Shape* and extracts the sub-shapes you specifically need.
-Generally, this explorer is created by providing the following information:
-
- * the shape to explore
- * the type of sub-shapes to be found. This information is given with the *TopAbs_ShapeEnum* enumeration.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
-TopExp_Explorer anEdgeExplorer(myBody, TopAbs_EDGE);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-An explorer is usually applied in a loop by using its three main methods:
-
- * *More()* to know if there are more sub-shapes to explore.
- * *Current()* to know which is the currently explored sub-shape (used only if the *More()* method returns true).
- * *Next()* to move onto the next sub-shape to explore.
-
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- while(anEdgeExplorer.More()){
- TopoDS_Edge anEdge = TopoDS::Edge(anEdgeExplorer.Current());
- //Add edge to fillet algorithm
- ...
- anEdgeExplorer.Next();
- }
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-In the explorer loop, you have found all the edges of the bottle shape. Each one must then be added in the *BRepFilletAPI_MakeFillet* instance with the *Add()* method. Do not forget to specify the radius of the fillet along with it.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- mkFillet.Add(myThickness / 12., anEdge);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Once this is done, you perform the last step of the procedure by asking for the filleted shape.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- myBody = mkFillet.Shape();
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB3_3 Adding the Neck
-
-
-To add a neck to the bottle, you will create a cylinder and fuse it to the body. The cylinder is to be positioned on the top face of the body with a radius of *myThickness* / 4. and a height of *myHeight* / 10.
-
-@image html /overview/tutorial/images/tutorial_image009.png
-@image latex /overview/tutorial/images/tutorial_image009.png
-
-To position the cylinder, you need to define a coordinate system with the *gp_Ax2* class defining a right-handed coordinate system from a point and two directions - the main (Z) axis direction and the X direction (the Y direction is computed from these two).
-To align the neck with the center of the top face, being in the global coordinate system (0, 0, *myHeight*), with its normal on the global Z axis, your local coordinate system can be defined as follows:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Pnt neckLocation(0, 0, myHeight);
- gp_Dir neckAxis = gp::DZ();
- gp_Ax2 neckAx2(neckLocation, neckAxis);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-To create a cylinder, use another class from the primitives construction package: the *BRepPrimAPI_MakeCylinder* class. The information you must provide is:
-
- * the coordinate system where the cylinder will be located;
- * the radius and height.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- Standard_Real myNeckRadius = myThickness / 4.;
- Standard_Real myNeckHeight = myHeight / 10;
- BRepPrimAPI_MakeCylinder MKCylinder(neckAx2, myNeckRadius, myNeckHeight);
- TopoDS_Shape myNeck = MKCylinder.Shape();
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-You now have two separate parts: a main body and a neck that you need to fuse together.
-The *BRepAlgoAPI* package provides services to perform Boolean operations between shapes, and especially: *common* (Boolean intersection), *cut* (Boolean subtraction) and *fuse* (Boolean union).
-Use *BRepAlgoAPI_Fuse* to fuse the two shapes:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- myBody = BRepAlgoAPI_Fuse(myBody, myNeck);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB3_4 Creating a Hollowed Solid
-
-
-Since a real bottle is used to contain liquid material, you should now create a hollowed solid from the bottle's top face.
-In Open CASCADE Technology, a hollowed solid is called a *Thick* *Solid* and is internally computed as follows:
-
- * Remove one or more faces from the initial solid to obtain the first wall W1 of the hollowed solid.
- * Create a parallel wall W2 from W1 at a distance D. If D is positive, W2 will be outside the initial solid, otherwise it will be inside.
- * Compute a solid from the two walls W1 and W2.
-
-@image html /overview/tutorial/images/tutorial_image010.png
-@image latex /overview/tutorial/images/tutorial_image010.png
-
-To compute a thick solid, you create an instance of the *BRepOffsetAPI_MakeThickSolid* class by giving the following information:
-
- * The shape, which must be hollowed.
- * The tolerance used for the computation (tolerance criterion for coincidence in generated shapes).
- * The thickness between the two walls W1 and W2 (distance D).
- * The face(s) to be removed from the original solid to compute the first wall W1.
-
-The challenging part in this procedure is to find the face to remove from your shape - the top face of the neck, which:
-
- * has a plane (planar surface) as underlying geometry;
- * is the highest face (in Z coordinates) of the bottle.
-
-To find the face with such characteristics, you will once again use an explorer to iterate on all the bottle's faces to find the appropriate one.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- for(TopExp_Explorer aFaceExplorer(myBody, TopAbs_FACE) ; aFaceExplorer.More() ; aFaceExplorer.Next()){
- TopoDS_Face aFace = TopoDS::Face(aFaceExplorer.Current());
- }
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-For each detected face, you need to access the geometric properties of the shape: use the *BRep_Tool* class for that. The most commonly used methods of this class are:
-
- * *Surface* to access the surface of a face;
- * *Curve* to access the 3D curve of an edge;
- * *Point* to access the 3D point of a vertex.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
-Handle(Geom_Surface) aSurface = BRep_Tool::Surface(aFace);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-As you can see, the *BRep_Tool::Surface* method returns an instance of the *Geom_Surface* class manipulated by handle. However, the *Geom_Surface* class does not provide information about the real type of the object *aSurface*, which could be an instance of *Geom_Plane*, *Geom_CylindricalSurface*, etc.
-All objects manipulated by handle, like *Geom_Surface*, inherit from the *Standard_Transient* class which provides two very useful methods concerning types:
-
- * *DynamicType* to know the real type of the object
- * *IsKind* to know if the object inherits from one particular type
-
-DynamicType returns the real type of the object, but you need to compare it with the existing known types to determine whether *aSurface* is a plane, a cylindrical surface or some other type.
-To compare a given type with the type you seek, use the *STANDARD_TYPE* macro, which returns the type of a class:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- if(aSurface->DynamicType() == STANDARD_TYPE(Geom_Plane)){
- //
- }
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-If this comparison is true, you know that the *aSurface* real type is *Geom_Plane*. You can then convert it from *Geom_Surface* to *Geom_Plane* by using the *DownCast()* method provided by each class inheriting *Standard_Transient*. As its name implies, this static method is used to downcast objects to a given type with the following syntax:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- Handle(Geom_Plane) aPlane = Handle(Geom_Plane)::DownCast(aSurface);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Remember that the goal of all these conversions is to find the highest face of the bottle lying on a plane. Suppose that you have these two global variables:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Face faceToRemove;
- Standard_Real zMax = -1;
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-You can easily find the plane whose origin is the biggest in Z knowing that the location of the plane is given with the *Geom_Plane::Location* method. For example:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Pnt aPnt = aPlane->Location();
- Standard_Real aZ = aPnt.Z();
- if(aZ > zMax){
- zMax = aZ;
- faceToRemove = aFace;
- }
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-You have now found the top face of the neck. Your final step before creating the hollowed solid is to put this face in a list. Since more than one face can be removed from the initial solid, the *BRepOffsetAPI_MakeThickSolid* constructor takes a list of faces as arguments.
-Open CASCADE Technology provides many collections for different kinds of objects: see *TColGeom* package for collections of objects from *Geom* package, *TColgp* package for collections of objects from gp package, etc.
-The collection for shapes can be found in the *TopTools* package. As *BRepOffsetAPI_MakeThickSolid* requires a list, use the *TopTools_ListOfShape* class.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopTools_ListOfShape facesToRemove;
- facesToRemove.Append(faceToRemove);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-All the necessary data are now available so you can create your hollowed solid by calling the *BRepOffsetAPI_MakeThickSolid* constructor:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- MyBody = BRepOffsetAPI_MakeThickSolid(myBody, facesToRemove, -myThickness / 50, 1.e-3);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@section sec4 Building the Threading
-
-
-@subsection OCCT_TUTORIAL_SUB4_1 Creating Surfaces
-
-
-Up to now, you have learned how to create edges out of 3D curves.
-You will now learn how to create an edge out of a 2D curve and a surface.
-To learn this aspect of Open CASCADE Technology, you will build helicoidal profiles out of 2D curves on cylindrical surfaces. The theory is more complex than in previous steps, but applying it is very simple.
-As a first step, you compute these cylindrical surfaces. You are already familiar with curves of the *Geom* package. Now you can create a cylindrical surface (*Geom_CylindricalSurface*) using:
-
- * a coordinate system;
- * a radius.
-
-Using the same coordinate system *neckAx2* used to position the neck, you create two cylindrical surfaces *Geom_CylindricalSurface* with the following radii:
-
-@image html /overview/tutorial/images/tutorial_image011.png
-@image latex /overview/tutorial/images/tutorial_image011.png
-
-Notice that one of the cylindrical surfaces is smaller than the neck. There is a good reason for this: after the thread creation, you will fuse it with the neck. So, we must make sure that the two shapes remain in contact.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- Handle(Geom_CylindricalSurface) aCyl1 = new Geom_CylindricalSurface(neckAx2, myNeckRadius * 0.99);
-
- Handle(Geom_CylindricalSurface) aCyl2 = new Geom_CylindricalSurface(neckAx2, myNeckRadius * 1.05);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB4_2 Defining 2D Curves
-
-
-To create the neck of the bottle, you made a solid cylinder based on a cylindrical surface. You will create the profile of threading by creating 2D curves on such a surface.
-All geometries defined in the *Geom* package are parameterized. This means that each curve or surface from Geom is computed with a parametric equation.
-A *Geom_CylindricalSurface* surface is defined with the following parametric equation:
-
-P(U, V) = O + R * (cos(U) * xDir + sin(U) * yDir) + V * zDir, where :
-
- * P is the point defined by parameters (U, V).
- * O, *Dir, yDir and zDir are respectively the origin, the X direction, Y direction and Z direction of the cylindrical surface local coordinate system.
- * R is the radius of the cylindrical surface.
- * U range is [0, 2PI] and V is infinite.
-
-@image html /overview/tutorial/images/tutorial_image012.png
-@image latex /overview/tutorial/images/tutorial_image012.png
-
-The advantage of having such parameterized geometries is that you can compute, for any (U, V) parameters of the surface:
-
- * the 3D point;
- * the derivative vectors of order 1, 2 to N at this point.
-
-There is another advantage of these parametric equations: you can consider a surface as a 2D parametric space defined with a (U, V) coordinate system. For example, consider the parametric ranges of the neck's surface:
-
-@image html /overview/tutorial/images/tutorial_image013.png
-@image latex /overview/tutorial/images/tutorial_image013.png
-
-Suppose that you create a 2D line on this parametric (U, V) space and compute its 3D parametric curve. Depending on the line definition, results are as follows:
-
-| Case | Parametric Equation | Parametric Curve |
-| :------------ | :----------------------------------------------------------- | :---------------------------------------------------------------------------- |
-| U = 0 | P(V) = O + V * zDir | Line parallel to the Z direction |
-| V = 0 | P(U) = O + R * (cos(U) * xDir + sin(U) * yDir) | Circle parallel to the (O, X, Y) plane |
-| U != 0 V != 0 | P(U, V) = O + R * (cos(U) * xDir + sin(U) * yDir) + V * zDir | Helicoidal curve describing the evolution of height and angle on the cylinder |
-
-The helicoidal curve type is exactly what you need. On the neck's surface, the evolution laws of this curve will be:
-
- * In V parameter: between 0 and myHeighNeck for the height description
- * In U parameter: between 0 and 2PI for the angle description. But, since a cylindrical surface is U periodic, you can decide to extend this angle evolution to 4PI as shown in the following drawing:
-
-@image html /overview/tutorial/images/tutorial_image014.png
-@image latex /overview/tutorial/images/tutorial_image014.png
-
-In this (U, V) parametric space, you will create a local (X, Y) coordinate system to position the curves to be created. This coordinate system will be defined with:
-
- * A center located in the middle of the neck's cylinder parametric space at (2*PI, myNeckHeight / 2) in U, V coordinates.
- * A X direction defined with the (2*PI, myNeckHeight/4) vector in U, V coordinates, so that the curves occupy half of the neck's surfaces.
-
-@image html /overview/tutorial/images/tutorial_image015.png
-@image latex /overview/tutorial/images/tutorial_image015.png
-
-To use 2D primitive geometry types of Open CASCADE Technology for defining a point and a coordinate system, you will once again instantiate classes from gp:
-
- * To define a 2D point from its X and Y coordinates, use the *gp_Pnt2d* class.
- * To define a 2D direction (unit vector) from its X and Y coordinates, use the gp_Dir2d class. The coordinates will automatically be normalized.
- * To define a 2D right-handed coordinate system, use the *gp_Ax2d* class, which is computed from a point (origin of the coordinate system) and a direction - the X direction of the coordinate system. The Y direction will be automatically computed.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Pnt2d aPnt(2. * M_PI, myNeckHeight / 2.);
- gp_Dir2d aDir(2. * M_PI, myNeckHeight / 4.);
- gp_Ax2d anAx2d(aPnt, aDir);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-You will now define the curves. As previously mentioned, these thread profiles are computed on two cylindrical surfaces. In the following figure, curves on the left define the base (on *aCyl1* surface) and the curves on the right define the top of the thread's shape (on *aCyl2* surface).
-
-@image html /overview/tutorial/images/tutorial_image016.png
-@image latex /overview/tutorial/images/tutorial_image016.png
-
-You have already used the *Geom* package to define 3D geometric entities. For 2D, you will use the *Geom2d* package. As for *Geom*, all geometries are parameterized. For example, a *Geom2d_Ellipse* ellipse is defined from:
-
- * a coordinate system whose origin is the ellipse center;
- * a major radius on the major axis defined by the X direction of the coordinate system;
- * a minor radius on the minor axis defined by the Y direction of the coordinate system.
-
-Supposing that:
-
- * Both ellipses have the same major radius of 2*PI,
- * Minor radius of the first ellipse is myNeckHeight / 10,
- * And the minor radius value of the second ellipse is a fourth of the first one,
-
-Your ellipses are defined as follows:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- Standard_Real aMajor = 2. * M_PI;
- Standard_Real aMinor = myNeckHeight / 10;
- Handle(Geom2d_Ellipse) anEllipse1 = new Geom2d_Ellipse(anAx2d, aMajor, aMinor);
- Handle(Geom2d_Ellipse) anEllipse2 = new Geom2d_Ellipse(anAx2d, aMajor, aMinor / 4);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-To describe portions of curves for the arcs drawn above, you define *Geom2d_TrimmedCurve* trimmed curves out of the created ellipses and two parameters to limit them.
-As the parametric equation of an ellipse is P(U) = O + (MajorRadius * cos(U) * XDirection) + (MinorRadius * sin(U) * YDirection), the ellipses need to be limited between 0 and M_PI.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- Handle(Geom2d_TrimmedCurve) anArc1 = new Geom2d_TrimmedCurve(anEllipse1, 0, M_PI);
- Handle(Geom2d_TrimmedCurve) anArc2 = new Geom2d_TrimmedCurve(anEllipse2, 0, M_PI);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The last step consists in defining the segment, which is the same for the two profiles: a line limited by the first and the last point of one of the arcs.
-To access the point corresponding to the parameter of a curve or a surface, you use the Value or D0 method (meaning 0th derivative), D1 method is for first derivative, D2 for the second one.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- gp_Pnt2d anEllipsePnt1 = anEllipse1->Value(0);
- gp_Pnt2d anEllipsePnt2;
- anEllipse1->D0(M_PI, anEllipsePnt2);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-When creating the bottle's profile, you used classes from the *GC* package, providing algorithms to create elementary geometries.
-In 2D geometry, this kind of algorithms is found in the *GCE2d* package. Class names and behaviors are similar to those in *GC*. For example, to create a 2D segment out of two points:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- Handle(Geom2d_TrimmedCurve) aSegment = GCE2d_MakeSegment(anEllipsePnt1, anEllipsePnt2);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB4_3 Building Edges and Wires
-
-
-As you did when creating the base profile of the bottle, you can now:
-
- * compute the edges of the neck's threading.
- * compute two wires out of these edges.
-
-@image html /overview/tutorial/images/tutorial_image017.png
-@image latex /overview/tutorial/images/tutorial_image017.png
-
-Previously, you have built:
-
- * two cylindrical surfaces of the threading
- * three 2D curves defining the base geometry of the threading
-
-To compute the edges out of these curves, once again use the *BRepBuilderAPI_MakeEdge* class. One of its constructors allows you to build an edge out of a curve described in the 2D parametric space of a surface.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Edge anEdge1OnSurf1 = BRepBuilderAPI_MakeEdge(anArc1, aCyl1);
- TopoDS_Edge anEdge2OnSurf1 = BRepBuilderAPI_MakeEdge(aSegment, aCyl1);
- TopoDS_Edge anEdge1OnSurf2 = BRepBuilderAPI_MakeEdge(anArc2, aCyl2);
- TopoDS_Edge anEdge2OnSurf2 = BRepBuilderAPI_MakeEdge(aSegment, aCyl2);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Now, you can create the two profiles of the threading, lying on each surface.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Wire threadingWire1 = BRepBuilderAPI_MakeWire(anEdge1OnSurf1, anEdge2OnSurf1);
- TopoDS_Wire threadingWire2 = BRepBuilderAPI_MakeWire(anEdge1OnSurf2, anEdge2OnSurf2);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Remember that these wires were built out of a surface and 2D curves.
-One important data item is missing as far as these wires are concerned: there is no information on the 3D curves. Fortunately, you do not need to compute this yourself, which can be a difficult task since the mathematics can be quite complex.
-When a shape contains all the necessary information except 3D curves, Open CASCADE Technology provides a tool to build them automatically. In the BRepLib tool package, you can use the *BuildCurves3d* method to compute 3D curves for all the edges of a shape.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- BRepLib::BuildCurves3d(threadingWire1);
- BRepLib::BuildCurves3d(threadingWire2);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@subsection OCCT_TUTORIAL_SUB4_4 Creating Threading
-
-
-You have computed the wires of the threading. The threading will be a solid shape, so you must now compute the faces of the wires, the faces allowing you to join the wires, the shell out of these faces and then the solid itself. This can be a lengthy operation.
-There are always faster ways to build a solid when the base topology is defined. You would like to create a solid out of two wires. Open CASCADE Technology provides a quick way to do this by building a loft: a shell or a solid passing through a set of wires in a given sequence.
-The loft function is implemented in the *BRepOffsetAPI_ThruSections* class, which you use as follows:
-
-@image html /overview/tutorial/images/tutorial_image018.png
-@image latex /overview/tutorial/images/tutorial_image018.png
-
- * Initialize the algorithm by creating an instance of the class. The first parameter of this constructor must be specified if you want to create a solid. By default, *BRepOffsetAPI_ThruSections* builds a shell.
- * Add the successive wires using the AddWire method.
- * Use the *CheckCompatibility* method to activate (or deactivate) the option that checks whether the wires have the same number of edges. In this case, wires have two edges each, so you can deactivate this option.
- * Ask for the resulting loft shape with the Shape method.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- BRepOffsetAPI_ThruSections aTool(Standard_True);
- aTool.AddWire(threadingWire1); aTool.AddWire(threadingWire2);
- aTool.CheckCompatibility(Standard_False);
- TopoDS_Shape myThreading = aTool.Shape();
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-@section sec5 Building the Resulting Compound
-
-
-You are almost done building the bottle. Use the *TopoDS_Compound* and *BRep_Builder* classes to build single shape from *myBody* and *myThreading*:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Compound aRes;
- BRep_Builder aBuilder;
- aBuilder.MakeCompound (aRes);
- aBuilder.Add (aRes, myBody);
- aBuilder.Add (aRes, myThreading);
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Congratulations! Your bottle is complete. Here is the result snapshot of the Tutorial application:
-
-@image html /overview/tutorial/images/tutorial_image019.png
-@image latex /overview/tutorial/images/tutorial_image019.png
-
-We hope that this tutorial has provided you with a feel for the industrial strength power of Open CASCADE Technology.
-If you want to know more and develop major projects using Open CASCADE Technology, we invite you to study our training, support, and consulting services on our site at http://www.opencascade.org/support. Our professional services can maximize the power of your Open CASCADE Technology applications.
-
-
-@section sec6 Appendix
-
-
-Complete definition of MakeBottle function (defined in the file src/MakeBottle.cxx of the Tutorial):
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~{.cpp}
- TopoDS_Shape MakeBottle(const Standard_Real myWidth, const Standard_Real myHeight,
- const Standard_Real myThickness)
- {
- // Profile : Define Support Points
- gp_Pnt aPnt1(-myWidth / 2., 0, 0);
- gp_Pnt aPnt2(-myWidth / 2., -myThickness / 4., 0);
- gp_Pnt aPnt3(0, -myThickness / 2., 0);
- gp_Pnt aPnt4(myWidth / 2., -myThickness / 4., 0);
- gp_Pnt aPnt5(myWidth / 2., 0, 0);
-
- // Profile : Define the Geometry
- Handle(Geom_TrimmedCurve) anArcOfCircle = GC_MakeArcOfCircle(aPnt2,aPnt3,aPnt4);
- Handle(Geom_TrimmedCurve) aSegment1 = GC_MakeSegment(aPnt1, aPnt2);
- Handle(Geom_TrimmedCurve) aSegment2 = GC_MakeSegment(aPnt4, aPnt5);
-
- // Profile : Define the Topology
- TopoDS_Edge anEdge1 = BRepBuilderAPI_MakeEdge(aSegment1);
- TopoDS_Edge anEdge2 = BRepBuilderAPI_MakeEdge(anArcOfCircle);
- TopoDS_Edge anEdge3 = BRepBuilderAPI_MakeEdge(aSegment2);
- TopoDS_Wire aWire = BRepBuilderAPI_MakeWire(anEdge1, anEdge2, anEdge3);
-
- // Complete Profile
- gp_Ax1 xAxis = gp::OX();
- gp_Trsf aTrsf;
-
- aTrsf.SetMirror(xAxis);
- BRepBuilderAPI_Transform aBRepTrsf(aWire, aTrsf);
- TopoDS_Shape aMirroredShape = aBRepTrsf.Shape();
- TopoDS_Wire aMirroredWire = TopoDS::Wire(aMirroredShape);
-
- BRepBuilderAPI_MakeWire mkWire;
- mkWire.Add(aWire);
- mkWire.Add(aMirroredWire);
- TopoDS_Wire myWireProfile = mkWire.Wire();
-
- // Body : Prism the Profile
- TopoDS_Face myFaceProfile = BRepBuilderAPI_MakeFace(myWireProfile);
- gp_Vec aPrismVec(0, 0, myHeight);
- TopoDS_Shape myBody = BRepPrimAPI_MakePrism(myFaceProfile, aPrismVec);
-
- // Body : Apply Fillets
- BRepFilletAPI_MakeFillet mkFillet(myBody);
- TopExp_Explorer anEdgeExplorer(myBody, TopAbs_EDGE);
- while(anEdgeExplorer.More()){
- TopoDS_Edge anEdge = TopoDS::Edge(anEdgeExplorer.Current());
- //Add edge to fillet algorithm
- mkFillet.Add(myThickness / 12., anEdge);
- anEdgeExplorer.Next();
- }
-
- myBody = mkFillet.Shape();
-
- // Body : Add the Neck
- gp_Pnt neckLocation(0, 0, myHeight);
- gp_Dir neckAxis = gp::DZ();
- gp_Ax2 neckAx2(neckLocation, neckAxis);
-
- Standard_Real myNeckRadius = myThickness / 4.;
- Standard_Real myNeckHeight = myHeight / 10.;
-
- BRepPrimAPI_MakeCylinder MKCylinder(neckAx2, myNeckRadius, myNeckHeight);
- TopoDS_Shape myNeck = MKCylinder.Shape();
-
- myBody = BRepAlgoAPI_Fuse(myBody, myNeck);
-
- // Body : Create a Hollowed Solid
- TopoDS_Face faceToRemove;
- Standard_Real zMax = -1;
-
- for(TopExp_Explorer aFaceExplorer(myBody, TopAbs_FACE); aFaceExplorer.More(); aFaceExplorer.Next()){
- TopoDS_Face aFace = TopoDS::Face(aFaceExplorer.Current());
- // Check if <aFace> is the top face of the bottle's neck
- Handle(Geom_Surface) aSurface = BRep_Tool::Surface(aFace);
- if(aSurface->DynamicType() == STANDARD_TYPE(Geom_Plane)){
- Handle(Geom_Plane) aPlane = Handle(Geom_Plane)::DownCast(aSurface);
- gp_Pnt aPnt = aPlane->Location();
- Standard_Real aZ = aPnt.Z();
- if(aZ > zMax){
- zMax = aZ;
- faceToRemove = aFace;
- }
- }
- }
-
- TopTools_ListOfShape facesToRemove;
- facesToRemove.Append(faceToRemove);
- myBody = BRepOffsetAPI_MakeThickSolid(myBody, facesToRemove, -myThickness / 50, 1.e-3);
- // Threading : Create Surfaces
- Handle(Geom_CylindricalSurface) aCyl1 = new Geom_CylindricalSurface(neckAx2, myNeckRadius * 0.99);
- Handle(Geom_CylindricalSurface) aCyl2 = new Geom_CylindricalSurface(neckAx2, myNeckRadius * 1.05);
-
- // Threading : Define 2D Curves
- gp_Pnt2d aPnt(2. * M_PI, myNeckHeight / 2.);
- gp_Dir2d aDir(2. * M_PI, myNeckHeight / 4.);
- gp_Ax2d anAx2d(aPnt, aDir);
-
- Standard_Real aMajor = 2. * M_PI;
- Standard_Real aMinor = myNeckHeight / 10;
-
- Handle(Geom2d_Ellipse) anEllipse1 = new Geom2d_Ellipse(anAx2d, aMajor, aMinor);
- Handle(Geom2d_Ellipse) anEllipse2 = new Geom2d_Ellipse(anAx2d, aMajor, aMinor / 4);
- Handle(Geom2d_TrimmedCurve) anArc1 = new Geom2d_TrimmedCurve(anEllipse1, 0, M_PI);
- Handle(Geom2d_TrimmedCurve) anArc2 = new Geom2d_TrimmedCurve(anEllipse2, 0, M_PI);
- gp_Pnt2d anEllipsePnt1 = anEllipse1->Value(0);
- gp_Pnt2d anEllipsePnt2 = anEllipse1->Value(M_PI);
-
- Handle(Geom2d_TrimmedCurve) aSegment = GCE2d_MakeSegment(anEllipsePnt1, anEllipsePnt2);
- // Threading : Build Edges and Wires
- TopoDS_Edge anEdge1OnSurf1 = BRepBuilderAPI_MakeEdge(anArc1, aCyl1);
- TopoDS_Edge anEdge2OnSurf1 = BRepBuilderAPI_MakeEdge(aSegment, aCyl1);
- TopoDS_Edge anEdge1OnSurf2 = BRepBuilderAPI_MakeEdge(anArc2, aCyl2);
- TopoDS_Edge anEdge2OnSurf2 = BRepBuilderAPI_MakeEdge(aSegment, aCyl2);
- TopoDS_Wire threadingWire1 = BRepBuilderAPI_MakeWire(anEdge1OnSurf1, anEdge2OnSurf1);
- TopoDS_Wire threadingWire2 = BRepBuilderAPI_MakeWire(anEdge1OnSurf2, anEdge2OnSurf2);
- BRepLib::BuildCurves3d(threadingWire1);
- BRepLib::BuildCurves3d(threadingWire2);
-
- // Create Threading
- BRepOffsetAPI_ThruSections aTool(Standard_True);
- aTool.AddWire(threadingWire1);
- aTool.AddWire(threadingWire2);
- aTool.CheckCompatibility(Standard_False);
-
- TopoDS_Shape myThreading = aTool.Shape();
-
- // Building the Resulting Compound
- TopoDS_Compound aRes;
- BRep_Builder aBuilder;
- aBuilder.MakeCompound (aRes);
- aBuilder.Add (aRes, myBody);
- aBuilder.Add (aRes, myThreading);
-
- return aRes;
- }
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
projects / occt.git / commitdiff
