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-- File: GeomAPI_Interpolate.cdl
-- Created: Thu Aug 18 15:50:24 1994
-- Author: Laurent PAINNOT
-- <lpa@metrox>
---Copyright: Matra Datavision 1994
class Interpolate from GeomAPI
---Purpose: This class is used to interpolate a BsplineCurve
-- passing through an array of points, with a C2
-- Continuity if tangency is not requested at the point.
-- If tangency is requested at the point the continuity will
-- be C1. If Perodicity is requested the curve will be closed
-- and the junction will be the first point given. The curve
-- will than be only C1
-- Describes functions for building a constrained 3D BSpline curve.
-- The curve is defined by a table of points
-- through which it passes, and if required:
-- - by a parallel table of reals which gives the
-- value of the parameter of each point through
-- which the resulting BSpline curve passes, and
-- - by vectors tangential to these points.
-- An Interpolate object provides a framework for:
-- - defining the constraints of the BSpline curve,
-- - implementing the interpolation algorithm, and
-- - consulting the results.
--
uses
Vec from gp,
Array1OfPnt from TColgp,
HArray1OfPnt from TColgp,
Array1OfVec from TColgp,
HArray1OfBoolean from TColStd,
HArray1OfReal from TColStd,
HArray1OfVec from TColgp,
BSplineCurve from Geom
raises
NotDone from StdFail,
ConstructionError from Standard
is
Create(Points : HArray1OfPnt from TColgp ;
PeriodicFlag : Boolean from Standard ;
Tolerance : Real)
---Purpose: Initializes an algorithm for constructing a
-- constrained BSpline curve passing through the points of the table Points.
-- Tangential vectors can then be assigned, using the function Load.
-- If PeriodicFlag is true, the constrained BSpline
-- curve will be periodic and closed. In this case,
-- the junction point is the first point of the table Points.
-- The tolerance value Tolerance is used to check that:
-- - points are not too close to each other, or
-- - tangential vectors (defined using the
-- function Load) are not too small.
-- The resulting BSpline curve will be "C2"
-- continuous, except where a tangency
-- constraint is defined on a point through which
-- the curve passes (by using the Load function).
-- In this case, it will be only "C1" continuous.
-- Once all the constraints are defined, use the
-- function Perform to compute the curve.
-- Warning
-- - There must be at least 2 points in the table Points.
-- - If PeriodicFlag is false, there must be as
-- many parameters in the array Parameters as
-- there are points in the array Points.
-- - If PeriodicFlag is true, there must be one
-- more parameter in the table Parameters: this
-- is used to give the parameter on the
-- resulting BSpline curve of the junction point
-- of the curve (which is also the first point of the table Points).
-- Exceptions
-- - Standard_ConstructionError if the
-- distance between two consecutive points in
-- the table Points is less than or equal to Tolerance.
-- - Standard_OutOfRange if:
-- - there are less than two points in the table Points, or
-- - conditions relating to the respective
-- number of elements in the parallel tables
-- Points and Parameters are not respected.
returns Interpolate from GeomAPI
raises ConstructionError from Standard ;
Create(Points : HArray1OfPnt from TColgp ;
Parameters : HArray1OfReal from TColStd;
PeriodicFlag : Boolean from Standard;
Tolerance : Real)
---Purpose: Initializes an algorithm for constructing a
-- constrained BSpline curve passing through the points of the table
-- Points, where the parameters of each of its
-- points are given by the parallel table Parameters.
-- Tangential vectors can then be assigned, using the function Load.
-- If PeriodicFlag is true, the constrained BSpline
-- curve will be periodic and closed. In this case,
-- the junction point is the first point of the table Points.
-- The tolerance value Tolerance is used to check that:
-- - points are not too close to each other, or
-- - tangential vectors (defined using the
-- function Load) are not too small.
-- The resulting BSpline curve will be "C2"
-- continuous, except where a tangency
-- constraint is defined on a point through which
-- the curve passes (by using the Load function).
-- In this case, it will be only "C1" continuous.
-- Once all the constraints are defined, use the
-- function Perform to compute the curve.
-- Warning
-- - There must be at least 2 points in the table Points.
-- - If PeriodicFlag is false, there must be as
-- many parameters in the array Parameters as
-- there are points in the array Points.
-- - If PeriodicFlag is true, there must be one
-- more parameter in the table Parameters: this
-- is used to give the parameter on the
-- resulting BSpline curve of the junction point
-- of the curve (which is also the first point of the table Points).
-- Exceptions
-- - Standard_ConstructionError if the
-- distance between two consecutive points in
-- the table Points is less than or equal to Tolerance.
-- - Standard_OutOfRange if:
-- - there are less than two points in the table Points, or
-- - conditions relating to the respective
-- number of elements in the parallel tables
-- Points and Parameters are not respected.
returns Interpolate from GeomAPI
raises ConstructionError from Standard ;
Load(me : in out;
InitialTangent : Vec from gp;
FinalTangent : Vec from gp;
Scale : Boolean from Standard = Standard_True)
---Purpose: Assigns this constrained BSpline curve to be
-- tangential to vectors InitialTangent and FinalTangent
-- at its first and last points respectively (i.e.
-- the first and last points of the table of
-- points through which the curve passes, as
-- defined at the time of initialization).
is static ;
Load(me : in out;
Tangents : Array1OfVec from TColgp ;
TangentFlags : HArray1OfBoolean from TColStd;
Scale : Boolean from Standard = Standard_True)
is static;
---Purpose: Assigns this constrained BSpline curve to be
-- tangential to vectors defined in the table Tangents,
-- which is parallel to the table of points
-- through which the curve passes, as
-- defined at the time of initialization. Vectors
-- in the table Tangents are defined only if
-- the flag given in the parallel table
-- TangentFlags is true: only these vectors
-- are set as tangency constraints.
ClearTangents(me : in out) ;
---Purpose: Clears all tangency constraints on this
-- constrained BSpline curve (as initialized by the function Load).
Perform(me : in out) ;
---Purpose: Computes the constrained BSpline curve.
-- Use the function IsDone to verify that the
-- computation is successful, and then the function Curve to obtain the result.
Curve(me)
returns BSplineCurve from Geom
---Purpose: Returns the computed BSpline curve.
-- Raises StdFail_NotDone if the interpolation fails.
---C++: return const &
---C++: alias "Standard_EXPORT operator Handle(Geom_BSplineCurve)() const;"
raises
NotDone from StdFail
is static;
IsDone(me)
returns Boolean from Standard
is static;
--- Purpose: Returns true if the constrained BSpline curve is successfully constructed.
-- Note: in this case, the result is given by the function Curve.
PerformNonPeriodic(me : in out)
---Purpose: Interpolates in a non periodic fashion
is private ;
PerformPeriodic(me : in out)
---Purpose: Interpolates in a C1 periodic fashion
is private ;
fields
myTolerance : Real from Standard ;
-- the 3D tolerance to check for degenerate points
myPoints : HArray1OfPnt from TColgp ;
-- the points to interpolates
myIsDone : Boolean from Standard ;
-- the algorithm did complete OK if Standard_True
myCurve : BSplineCurve from Geom ;
-- the interpolated curve
myTangents : HArray1OfVec from TColgp ;
-- the tangents only defined at slot i if
-- myTangenFlags->Value(i) is Standard_True
myTangentFlags : HArray1OfBoolean from TColStd ;
-- the flags defining the tangents
myParameters : HArray1OfReal from TColStd ;
-- the parameters used for the cubic interpolation
myPeriodic : Boolean from Standard ;
-- if Standard_True the curve will be periodic
myTangentRequest : Boolean from Standard ;
-- Tangents are given if True False otherwise
end Interpolate;
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