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-- File: GeomLib.cdl
-- Created: Wed Jul 7 12:38:18 1993
-- Author: Jean Claude VAUTHIER
---Copyright: Matra Datavision 1993
-- jct : modified 15-Apr-97 : added method ExtendSurfByLength
package GeomLib
---Purpose: Geom Library. This package provides an
-- implementation of functions for basic computation
-- on geometric entity from packages Geom and Geom2d.
uses
TCollection,
TColStd,
TColgp,
TColGeom,
TColGeom2d,
Adaptor3d,
AdvApprox,
Geom,
Geom2d,
GeomAbs,
math,
gp,
StdFail
is
enumeration InterpolationErrors is
---Purpose: in case the interpolation errors out, this
-- tells what happened
NoError,
NotEnoughtPoints,
DegreeSmallerThan3,
InversionProblem
end InterpolationErrors;
-- -- --------------- --
-- C L A S S E S --
-- --------------- --
class Array1OfMat instantiates
Array1 from TCollection (Mat from gp);
class MakeCurvefromApprox;
---Purpose: This class is used to create the curves ( 2d or
-- 3d) rational or not created by the class
-- ApproxAFunction from AdvApprox.
class Interpolate ;
---Purpose: this class compute the poles of a curve given some
-- parameters, points to interpolate and boundary conditions
-- in 3d
class DenominatorMultiplier ;
---Purpose: this defines an evaluator for a function of 2 variables
-- that will be used by CancelDenominatorDerivative in one
-- direction.
class CheckBSplineCurve ;
---Purpose: Checks for the end tangents : wether or not those
-- are reversed regarding the third or n-3rd control
--
--
class Check2dBSplineCurve ;
---Purpose: Checks for the end tangents : wether or not those
-- are reversed
class IsPlanarSurface;
class Tool;
---Purpose: provides various methods with Geom2d and Geom curves
--- and surfaces.
private class PolyFunc;
private class LogSample;
pointer DenominatorMultiplierPtr to DenominatorMultiplier from GeomLib ;
-------------------------
-- M E T H O D E S --
-- ----------------- --
To3d (Position : in Ax2 from gp;
Curve2d : in Curve from Geom2d)
returns Curve from Geom;
---Purpose: Computes the curve 3d from package Geom
-- corresponding to curve 2d from package Geom2d, on
-- the plan defined with the local coordinate system
-- Position.
GTransform( Curve : in Curve from Geom2d;
GTrsf : in GTrsf2d from gp)
returns Curve from Geom2d;
---Purpose: Computes the curve 3d from package Geom
-- corresponding to the curve 3d from package Geom,
-- transformed with the transformation <GTrsf>
-- WARNING : this method may return a null Handle if
-- it's impossible to compute the transformation of
-- a curve. It's not implemented when :
-- 1) the curve is an infinite parabola or hyperbola
-- 2) the curve is an offsetcurve
SameRange(Tolerance : in Real from Standard ;
Curve2dPtr : in Curve from Geom2d ;
First : in Real from Standard ;
Last : in Real from Standard ;
RequestedFirst : in Real from Standard ;
RequestedLast : in Real from Standard ;
NewCurve2dPtr : out Curve from Geom2d) ;
---Purpose: Make the curve Curve2dPtr have the imposed
-- range First to List the most economic way,
-- that is if it can change the range without
-- changing the nature of the curve it will try
-- to do that. Otherwise it will produce a Bspline
-- curve that has the required range
BuildCurve3d(Tolerance : in Real from Standard ;
CurvePtr : in out CurveOnSurface from Adaptor3d ;
FirstParameter : in Real from Standard ;
LastParameter : in Real from Standard ;
NewCurvePtr : out Curve from Geom ;
MaxDeviation : out Real from Standard ;
AverageDeviation : out Real from Standard ;
Continuity : Shape from GeomAbs = GeomAbs_C1;
MaxDegree : Integer = 14;
MaxSegment : Integer = 30);
AdjustExtremity(Curve : in out BoundedCurve from Geom;
P1, P2 : Pnt from gp;
T1, T2 : Vec from gp);
ExtendCurveToPoint(Curve : in out BoundedCurve from Geom;
Point : Pnt from gp;
Cont : Integer from Standard;
After : Boolean from Standard);
---Purpose: Extends the bounded curve Curve to the point Point.
-- The extension is built:
-- - at the end of the curve if After equals true, or
-- - at the beginning of the curve if After equals false.
-- The extension is performed according to a degree of
-- continuity equal to Cont, which in its turn must be equal to 1, 2 or 3.
-- This function converts the bounded curve Curve into a BSpline curve.
-- Warning
-- - Nothing is done, and Curve is not modified if Cont is
-- not equal to 1, 2 or 3.
-- - It is recommended that the extension should not be
-- too large with respect to the size of the bounded
-- curve Curve: Point must not be located too far from
-- one of the extremities of Curve.
ExtendSurfByLength(Surf : in out BoundedSurface from Geom;
Length : Real from Standard;
Cont : Integer from Standard;
InU : Boolean from Standard;
After : Boolean from Standard);
---Purpose:
-- Extends the bounded surface Surf along one of its
-- boundaries. The chord length of the extension is equal to Length.
-- The direction of the extension is given as:
-- - the u parametric direction of Surf, if InU equals true, or
-- - the v parametric direction of Surf, if InU equals false.
-- In this parametric direction, the extension is built on the side of:
-- - the last parameter of Surf, if After equals true, or
-- - the first parameter of Surf, if After equals false.
-- The extension is performed according to a degree of
-- continuity equal to Cont, which in its turn must be equal to 1, 2 or 3.
-- This function converts the bounded surface Surf into a BSpline surface.
-- Warning
-- - Nothing is done, and Surf is not modified if Cont is
-- not equal to 1, 2 or 3.
-- - It is recommended that Length, the size of the
-- extension should not be too large with respect to the
-- size of the bounded surface Surf.
-- - Surf must not be a periodic BSpline surface in the
-- parametric direction corresponding to the direction of extension.
AxeOfInertia(Points : Array1OfPnt from TColgp;
Axe : out Ax2 from gp;
IsSingular : out Boolean;
Tol : Real = 1.0e-7);
---Purpose: Compute axes of inertia, of some points -- -- --
-- <Axe>.Location() is the BaryCentre -- -- -- -- --
-- <Axe>.XDirection is the axe of upper inertia -- -- --
-- -- <Axe>.Direction is the Normal to the average plane
-- -- -- -- IsSingular is True if points are on line --
-- Tol is used to determine singular cases.
Inertia(Points : Array1OfPnt from TColgp;
Bary : out Pnt from gp;
XDir,YDir : out Dir from gp;
Xgap,YGap,ZGap : out Real);
---Level: Advanced
---Purpose: Compute principale axes of inertia, and dispertion
-- value of some points.
RemovePointsFromArray(NumPoints : Integer from Standard ;
InParameters : Array1OfReal from TColStd ;
OutParameters : in out HArray1OfReal from TColStd) ;
---Purpose: Warning! This assume that the InParameter is an increasing sequence
-- of real number and it will not check for that : Unpredictable
-- result can happen if this is not satisfied. It is the caller
-- responsability to check for that property.
--
-- This method makes uniform NumPoints segments S1,...SNumPoints out
-- of the segment defined by the first parameter and the
-- last parameter ofthe InParameter ; keeps only one
-- point of the InParameters set of parameter in each of
-- the uniform segments taking care of the first and the
-- last parameters. For the ith segment the element of
-- the InParameter is the one that is the first to exceed
-- the midpoint of the segment and to fall before the
-- midpoint of the next segment
-- There will be at the end at most NumPoints + 1 if
-- NumPoints > 2 in the OutParameters Array
DensifyArray1OfReal(MinNumPoints : Integer from Standard ;
InParameters : Array1OfReal from TColStd ;
OutParameters : in out HArray1OfReal from TColStd) ;
---Purpose: this makes sure that there is at least MinNumPoints
-- in OutParameters taking into account the parameters in
-- the InParameters array provided those are in order,
-- that is the sequence of real in the InParameter is strictly
-- non decreasing
--
FuseIntervals(Interval1, Interval2 : Array1OfReal from TColStd;
Fusion : out SequenceOfReal from TColStd;
Confusion : Real = 1.0e-9);
EvalMaxParametricDistance(Curve : Curve from Adaptor3d ;
AReferenceCurve : Curve from Adaptor3d ;
Tolerance : Real from Standard ;
Parameters : Array1OfReal from TColStd ;
MaxDistance : out Real from Standard) ;
---Purpose: this will compute the maximum distance at the
-- parameters given in the Parameters array by
-- evaluating each parameter the two curves and taking
-- the maximum of the evaluated distance
EvalMaxDistanceAlongParameter(Curve : Curve from Adaptor3d ;
AReferenceCurve : Curve from Adaptor3d ;
Tolerance : Real from Standard ;
Parameters : Array1OfReal from TColStd ;
MaxDistance : out Real from Standard) ;
---Purpose: this will compute the maximum distancef at the parameters
-- given in the Parameters array by projecting from the Curve
-- to the reference curve and taking the minimum distance
-- Than the maximum will be taken on those minimas.
CancelDenominatorDerivative(BSurf : in out BSplineSurface from Geom ;
UDirection : in Boolean from Standard ;
VDirection : in Boolean from Standard) ;
---Purpose: Cancel,on the boudaries,the denominator first derivative
-- in the directions wished by the user and set its value to 1.
-- TensorialProduct(S : in out BSplineSurface from Geom;
-- Poles : Array1OfMat from GeomLib;
-- TPoles : Array1OfPnt from TColgp;
-- Knots : Array1OfReal from TColStd;
-- Mults : Array1OfInteger from TColStd);
-- Purpose: Compute the Tensorial product beetween an
-- BSplineSurface <S>(U,V) and an Transformation Law M(v)
-- given by NUBS form (<Poles>, <Knots>, <Mults>). The result
-- Surface is R(U,V) = M(V)*S(U,V)+T(V).
NormEstim(S : Surface from Geom;
UV : Pnt2d from gp;
Tol : Real from Standard;
N : in out Dir from gp)
returns Integer from Standard;
-- Purpose: Computes normal of surface S in UV point UV
-- for regular point N = DU^DV
-- if |DU| < Tol or |DV| < Tol special treatment is used:
-- N is computed on base of normal of corresponding isoline
-- of S
-- returns 0 for regular point,
-- 1 for quasysingular (ex.: sphere pole)
-- 2 for conical singular point
-- 3 if computation impossible (for ex. DU||DV - tangent isolines)
end GeomLib;
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