1 // Created on: 1994-08-18
2 // Created by: Laurent PAINNOT
3 // Copyright (c) 1994-1999 Matra Datavision
4 // Copyright (c) 1999-2014 OPEN CASCADE SAS
6 // This file is part of Open CASCADE Technology software library.
8 // This library is free software; you can redistribute it and/or modify it under
9 // the terms of the GNU Lesser General Public License version 2.1 as published
10 // by the Free Software Foundation, with special exception defined in the file
11 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
12 // distribution for complete text of the license and disclaimer of any warranty.
14 // Alternatively, this file may be used under the terms of Open CASCADE
15 // commercial license or contractual agreement.
17 #ifndef _GeomAPI_Interpolate_HeaderFile
18 #define _GeomAPI_Interpolate_HeaderFile
20 #include <Standard.hxx>
21 #include <Standard_DefineAlloc.hxx>
22 #include <Standard_Handle.hxx>
24 #include <Standard_Real.hxx>
25 #include <TColgp_HArray1OfPnt.hxx>
26 #include <Standard_Boolean.hxx>
27 #include <TColgp_HArray1OfVec.hxx>
28 #include <TColStd_HArray1OfBoolean.hxx>
29 #include <TColStd_HArray1OfReal.hxx>
30 #include <TColgp_Array1OfVec.hxx>
31 #include <Geom_BSplineCurve.hxx>
36 //! This class is used to interpolate a BsplineCurve
37 //! passing through an array of points, with a C2
38 //! Continuity if tangency is not requested at the point.
39 //! If tangency is requested at the point the continuity will
40 //! be C1. If Perodicity is requested the curve will be closed
41 //! and the junction will be the first point given. The curve
42 //! will than be only C1
43 //! Describes functions for building a constrained 3D BSpline curve.
44 //! The curve is defined by a table of points
45 //! through which it passes, and if required:
46 //! - by a parallel table of reals which gives the
47 //! value of the parameter of each point through
48 //! which the resulting BSpline curve passes, and
49 //! - by vectors tangential to these points.
50 //! An Interpolate object provides a framework for:
51 //! - defining the constraints of the BSpline curve,
52 //! - implementing the interpolation algorithm, and
53 //! - consulting the results.
54 class GeomAPI_Interpolate
61 //! Initializes an algorithm for constructing a
62 //! constrained BSpline curve passing through the points of the table Points.
63 //! Tangential vectors can then be assigned, using the function Load.
64 //! If PeriodicFlag is true, the constrained BSpline
65 //! curve will be periodic and closed. In this case,
66 //! the junction point is the first point of the table Points.
67 //! The tolerance value Tolerance is used to check that:
68 //! - points are not too close to each other, or
69 //! - tangential vectors (defined using the
70 //! function Load) are not too small.
71 //! The resulting BSpline curve will be "C2"
72 //! continuous, except where a tangency
73 //! constraint is defined on a point through which
74 //! the curve passes (by using the Load function).
75 //! In this case, it will be only "C1" continuous.
76 //! Once all the constraints are defined, use the
77 //! function Perform to compute the curve.
79 //! - There must be at least 2 points in the table Points.
80 //! - If PeriodicFlag is false, there must be as
81 //! many parameters in the array Parameters as
82 //! there are points in the array Points.
83 //! - If PeriodicFlag is true, there must be one
84 //! more parameter in the table Parameters: this
85 //! is used to give the parameter on the
86 //! resulting BSpline curve of the junction point
87 //! of the curve (which is also the first point of the table Points).
89 //! - Standard_ConstructionError if the
90 //! distance between two consecutive points in
91 //! the table Points is less than or equal to Tolerance.
92 //! - Standard_OutOfRange if:
93 //! - there are less than two points in the table Points, or
94 //! - conditions relating to the respective
95 //! number of elements in the parallel tables
96 //! Points and Parameters are not respected.
97 Standard_EXPORT GeomAPI_Interpolate(const Handle(TColgp_HArray1OfPnt)& Points, const Standard_Boolean PeriodicFlag, const Standard_Real Tolerance);
99 //! Initializes an algorithm for constructing a
100 //! constrained BSpline curve passing through the points of the table
101 //! Points, where the parameters of each of its
102 //! points are given by the parallel table Parameters.
103 //! Tangential vectors can then be assigned, using the function Load.
104 //! If PeriodicFlag is true, the constrained BSpline
105 //! curve will be periodic and closed. In this case,
106 //! the junction point is the first point of the table Points.
107 //! The tolerance value Tolerance is used to check that:
108 //! - points are not too close to each other, or
109 //! - tangential vectors (defined using the
110 //! function Load) are not too small.
111 //! The resulting BSpline curve will be "C2"
112 //! continuous, except where a tangency
113 //! constraint is defined on a point through which
114 //! the curve passes (by using the Load function).
115 //! In this case, it will be only "C1" continuous.
116 //! Once all the constraints are defined, use the
117 //! function Perform to compute the curve.
119 //! - There must be at least 2 points in the table Points.
120 //! - If PeriodicFlag is false, there must be as
121 //! many parameters in the array Parameters as
122 //! there are points in the array Points.
123 //! - If PeriodicFlag is true, there must be one
124 //! more parameter in the table Parameters: this
125 //! is used to give the parameter on the
126 //! resulting BSpline curve of the junction point
127 //! of the curve (which is also the first point of the table Points).
129 //! - Standard_ConstructionError if the
130 //! distance between two consecutive points in
131 //! the table Points is less than or equal to Tolerance.
132 //! - Standard_OutOfRange if:
133 //! - there are less than two points in the table Points, or
134 //! - conditions relating to the respective
135 //! number of elements in the parallel tables
136 //! Points and Parameters are not respected.
137 Standard_EXPORT GeomAPI_Interpolate(const Handle(TColgp_HArray1OfPnt)& Points, const Handle(TColStd_HArray1OfReal)& Parameters, const Standard_Boolean PeriodicFlag, const Standard_Real Tolerance);
139 //! Assigns this constrained BSpline curve to be
140 //! tangential to vectors InitialTangent and FinalTangent
141 //! at its first and last points respectively (i.e.
142 //! the first and last points of the table of
143 //! points through which the curve passes, as
144 //! defined at the time of initialization).
145 Standard_EXPORT void Load (const gp_Vec& InitialTangent, const gp_Vec& FinalTangent, const Standard_Boolean Scale = Standard_True);
147 //! Assigns this constrained BSpline curve to be
148 //! tangential to vectors defined in the table Tangents,
149 //! which is parallel to the table of points
150 //! through which the curve passes, as
151 //! defined at the time of initialization. Vectors
152 //! in the table Tangents are defined only if
153 //! the flag given in the parallel table
154 //! TangentFlags is true: only these vectors
155 //! are set as tangency constraints.
156 Standard_EXPORT void Load (const TColgp_Array1OfVec& Tangents, const Handle(TColStd_HArray1OfBoolean)& TangentFlags, const Standard_Boolean Scale = Standard_True);
158 //! Clears all tangency constraints on this
159 //! constrained BSpline curve (as initialized by the function Load).
160 Standard_EXPORT void ClearTangents();
162 //! Computes the constrained BSpline curve.
163 //! Use the function IsDone to verify that the
164 //! computation is successful, and then the function Curve to obtain the result.
165 Standard_EXPORT void Perform();
167 //! Returns the computed BSpline curve.
168 //! Raises StdFail_NotDone if the interpolation fails.
169 Standard_EXPORT const Handle(Geom_BSplineCurve)& Curve() const;
170 Standard_EXPORT operator Handle(Geom_BSplineCurve)() const;
172 //! Returns true if the constrained BSpline curve is successfully constructed.
173 //! Note: in this case, the result is given by the function Curve.
174 Standard_EXPORT Standard_Boolean IsDone() const;
188 //! Interpolates in a non periodic fashion
189 Standard_EXPORT void PerformNonPeriodic();
191 //! Interpolates in a C1 periodic fashion
192 Standard_EXPORT void PerformPeriodic();
195 Standard_Real myTolerance;
196 Handle(TColgp_HArray1OfPnt) myPoints;
197 Standard_Boolean myIsDone;
198 Handle(Geom_BSplineCurve) myCurve;
199 Handle(TColgp_HArray1OfVec) myTangents;
200 Handle(TColStd_HArray1OfBoolean) myTangentFlags;
201 Handle(TColStd_HArray1OfReal) myParameters;
202 Standard_Boolean myPeriodic;
203 Standard_Boolean myTangentRequest;
214 #endif // _GeomAPI_Interpolate_HeaderFile