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Mostly duplicated comments were removed and missing ones were moved into dedicated class CDL files. Some more duplicated comments were removed from CDL files. Correction of merge
196 lines
8.2 KiB
Plaintext
196 lines
8.2 KiB
Plaintext
-- Created on: 1991-09-09
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-- Created by: Michel Chauvat
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-- Copyright (c) 1991-1999 Matra Datavision
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-- Copyright (c) 1999-2014 OPEN CASCADE SAS
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--
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-- This file is part of Open CASCADE Technology software library.
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--
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-- This library is free software; you can redistribute it and/or modify it under
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-- the terms of the GNU Lesser General Public License version 2.1 as published
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-- by the Free Software Foundation, with special exception defined in the file
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-- OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
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-- distribution for complete text of the license and disclaimer of any warranty.
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--
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-- Alternatively, this file may be used under the terms of Open CASCADE
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-- commercial license or contractual agreement.
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-- JCV Decembre 1991
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package CSLib
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---Purpose: This package implements functions for basis geometric
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-- computation on curves and surfaces.
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-- The tolerance criterions used in this package are
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-- Resolution from package gp and RealEpsilon from class
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-- Real of package Standard.
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uses gp,
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TColgp,
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TColStd,
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math
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is
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enumeration DerivativeStatus is
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Done, D1uIsNull, D1vIsNull, D1IsNull, D1uD1vRatioIsNull,
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D1vD1uRatioIsNull, D1uIsParallelD1v;
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--- Purpose :
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--
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-- D1uIsNull : ||D1U|| <= Resolution
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--
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-- D1vIsNull : ||D1V|| <= Resolution
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--
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-- D1IsNull : the first derivatives in the U and V parametric
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-- directions have null length :
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-- ||D1U|| <= Resolution and ||D1V|| <= Resolution
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--
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-- D1uD1vRatioIsNull : the first derivative in the U direction has
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-- null length by comparison with the derivative
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-- in the V direction
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-- ||D1U|| / ||D1V|| <= RealEpsilon
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--
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-- D1vD1uRatioIsNull : the first derivative in the V direction has
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-- null length by comparison with the derivative
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-- in the U direction
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-- ||D1V|| / ||D1U|| <= RealEpsilon
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--
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-- D1uIsParallelD1v : the angle between the derivatives in the U and
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-- V direction is null (tolerance criterion given
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-- as input data)
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enumeration NormalStatus is
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Singular,Defined,InfinityOfSolutions, D1NuIsNull, D1NvIsNull, D1NIsNull,
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D1NuNvRatioIsNull, D1NvNuRatioIsNull, D1NuIsParallelD1Nv;
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--- Purpose :
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--
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-- if N is the normal
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--
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-- InfinityOfSolutions : ||DN/du||>Resolution, ||DN/dv||>Resolution
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--
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-- D1NuIsNull : ||DN/du|| <= Resolution
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--
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-- D1NvIsNull : ||DN/dv|| <= Resolution
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--
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-- D1NIsNull : ||DN/du||<=Resolution, ||DN/dv||<=Resolution
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--
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-- D1NuNvRatioIsNull : ||D1Nu|| / ||D1Nv|| <= RealEpsilon
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--
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-- D1NvNuRatioIsNull : ||D1Nu|| / ||D1Nv|| <= RealEpsilon
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--
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-- D1NuIsParallelD1Nv : The angle between D1Nu and D1Nv is Null.
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class Class2d;
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private class NormalPolyDef;
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--- Purpose :
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-- The following functions computes the normal to a surface
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-- inherits FunctionWithDerivative from math
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--
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Normal (D1U, D1V: Vec from gp; SinTol: Real;
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Status: out DerivativeStatus;
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Normal: out Dir from gp);
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--- Purpose :
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-- Computes the normal direction of a surface as the cross product
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-- between D1U and D1V.
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-- If D1U has null length or D1V has null length or D1U and D1V are
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-- parallel the normal is undefined.
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-- To check that D1U and D1V are colinear the sinus of the angle
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-- between D1U and D1V is computed and compared with SinTol.
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-- The normal is computed if Status == Done else the Status gives the
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-- reason why the computation has failed.
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Normal (D1U, D1V, D2U, D2V, D2UV: Vec from gp; SinTol: Real;
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Done : out Boolean; Status : out NormalStatus;
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Normal: out Dir from gp);
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--- Purpose :
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-- If there is a singularity on the surface the previous method
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-- cannot compute the local normal.
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-- This method computes an approched normal direction of a surface.
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-- It does a limited development and needs the second derivatives
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-- on the surface as input data.
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-- It computes the normal as follow :
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-- N(u, v) = D1U ^ D1V
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-- N(u0+du,v0+dv) = N0 + DN/du(u0,v0) * du + DN/dv(u0,v0) * dv + Eps
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-- with Eps->0 so we can have the equivalence N ~ dN/du + dN/dv.
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-- DNu = ||DN/du|| and DNv = ||DN/dv||
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--
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-- . if DNu IsNull (DNu <= Resolution from gp) the answer Done = True
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-- the normal direction is given by DN/dv
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-- . if DNv IsNull (DNv <= Resolution from gp) the answer Done = True
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-- the normal direction is given by DN/du
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-- . if the two directions DN/du and DN/dv are parallel Done = True
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-- the normal direction is given either by DN/du or DN/dv.
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-- To check that the two directions are colinear the sinus of the
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-- angle between these directions is computed and compared with
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-- SinTol.
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-- . if DNu/DNv or DNv/DNu is lower or equal than Real Epsilon
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-- Done = False, the normal is undefined
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-- . if DNu IsNull and DNv is Null Done = False, there is an
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-- indetermination and we should do a limited developpement at
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-- order 2 (it means that we cannot omit Eps).
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-- . if DNu Is not Null and DNv Is not Null Done = False, there are
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-- an infinity of normals at the considered point on the surface.
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Normal (D1U, D1V: Vec from gp; MagTol: Real;
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Status: out NormalStatus;
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Normal: out Dir from gp);
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--- Purpose :
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-- Computes the normal direction of a surface as the cross product
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-- between D1U and D1V.
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--
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Normal (MaxOrder : Integer ; DerNUV : Array2OfVec from TColgp; MagTol: Real;
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U , V , Umin , Umax , Vmin , Vmax : Real; Status: out NormalStatus;
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Normal : out Dir from gp; OrderU , OrderV : out Integer);
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--- Purpose : find the first order k0 of deriviative of NUV
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-- where: foreach order < k0 all the derivatives of NUV are
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-- null all the derivatives of NUV corresponding to the order
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-- k0 are collinear and have the same sens.
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-- In this case, normal at U,V is unique.
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DNNUV ( Nu , Nv : Integer; DerSurf : Array2OfVec from TColgp )
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returns Vec from gp;
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---Purpose : -- Computes the derivative of order Nu in the --
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-- direction U and Nv in the direction V of the not --
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-- normalized normal vector at the point P(U,V) The
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-- array DerSurf contain the derivative (i,j) of the surface
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-- for i=0,Nu+1 ; j=0,Nv+1
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DNNUV (Nu,Nv : Integer ; DerSurf1 : Array2OfVec from TColgp;
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DerSurf2 : Array2OfVec from TColgp )
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returns Vec from gp;
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---Purpose : Computes the derivatives of order Nu in the direction Nu
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-- and Nv in the direction Nv of the not normalized vector
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-- N(u,v) = dS1/du * dS2/dv (cases where we use an osculating surface)
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-- DerSurf1 are the derivatives of S1
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DNNormal( Nu , Nv : Integer; DerNUV : Array2OfVec from TColgp ;
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Iduref : Integer = 0; Idvref : Integer = 0 )
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returns Vec from gp;
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---Purpose : -- Computes the derivative of order Nu in the --
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-- direction U and Nv in the direction V of the
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-- normalized normal vector at the point P(U,V) array
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-- DerNUV contain the derivative (i+Iduref,j+Idvref)
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-- of D1U ^ D1V for i=0,Nu ; j=0,Nv Iduref and Idvref
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-- correspond to a derivative of D1U ^ D1V which can
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-- be used to compute the normalized normal vector.
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-- In the regular cases , Iduref=Idvref=0.
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end CSLib;
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