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// File: Extrema_FuncExtPS.cxx
// Created: Tue Jul 18 08:11:24 1995
// Author: Modelistation
// <model@metrox>
// Modified by skv - Thu Sep 30 15:21:07 2004 OCC593
#include <Extrema_FuncExtPS.ixx>
#include <gp_Vec.hxx>
#include <gp_Pnt.hxx>
#include <Standard_TypeMismatch.hxx>
#include <Precision.hxx>
#include <GeomAbs_IsoType.hxx>
/*-----------------------------------------------------------------------------
Fonctions permettant de rechercher une distance extremale entre un point P
et une surface S (en partant d'un point approche S(u0,v0)).
Cette classe herite de math_FunctionSetWithDerivatives et est utilisee par
l'algorithme math_FunctionSetRoot.
Si on note Dus et Dvs, les derivees en u et v, les 2 fonctions a annuler sont:
{ F1(u,v) = (S(u,v)-P).Dus(u,v) }
{ F2(u,v) = (S(u,v)-P).Dvs(u,v) }
Si on note Duus, Dvvs et Duvs, les derivees secondes de S, les derivees de F1
et F2 sont egales a:
{ Duf1(u,v) = Dus(u,v).Dus(u,v) + (S(u,v)-P).Duus(u,v)
= ||Dus(u,v)|| ** 2 + (S(u,v)-P).Duus(u,v)
{ Dvf1(u,v) = Dvs(u,v).Dus(u,v) + (S(u,v)-P).Duvs(u,v)
{ Duf2(u,v) = Dus(u,v).Dvs(u,v) + (S(u,v)-P).Duvs(u,v) = dF1v(u,v)
{ Dvf2(u,v) = Dvs(u,v).Dvs(u,v) + (S(u,v)-P).Dvvs(u,v)
= ||Dvs(u,v)|| ** 2 + (S(u,v)-P).Dvvs(u,v)
----------------------------------------------------------------------------*/
// modified by NIZHNY-EAP Wed Nov 21 17:33:05 2001
// -- Dus and Dvs normalized, Df modified accordingly (BUC61043)
//=============================================================================
//------------------------------------------------------------------------------
// This method checks if isocurve is punctual (for details see Geom_OffsetSurface
// and Geom_OsculatingSurface
//-------------------------------------------------------------------------------
static Standard_Boolean IsoIsDeg (const Adaptor3d_Surface& S,
const Standard_Real Param,
const GeomAbs_IsoType IT,
const Standard_Real TolMin,
const Standard_Real TolMax)
{
Standard_Real U1=0.,U2=0.,V1=0.,V2=0.,T;
Standard_Boolean Along = Standard_True;
U1 = S.FirstUParameter();
U2 = S.LastUParameter();
V1 = S.FirstVParameter();
V2 = S.LastVParameter();
gp_Vec D1U,D1V;
gp_Pnt P;
Standard_Real Step,D1NormMax;
if (IT == GeomAbs_IsoV)
{
Step = (U2 - U1)/10;
D1NormMax=0.;
for (T=U1;T<=U2;T=T+Step)
{
S.D1(T,Param,P,D1U,D1V);
D1NormMax=Max(D1NormMax,D1U.Magnitude());
}
if (D1NormMax >TolMax || D1NormMax < TolMin )
Along = Standard_False;
}
else
{
Step = (V2 - V1)/10;
D1NormMax=0.;
for (T=V1;T<=V2;T=T+Step)
{
S.D1(Param,T,P,D1U,D1V);
D1NormMax=Max(D1NormMax,D1V.Magnitude());
}
if (D1NormMax >TolMax || D1NormMax < TolMin )
Along = Standard_False;
}
return Along;
}
Extrema_FuncExtPS::Extrema_FuncExtPS ()
{
myPinit = Standard_False;
mySinit = Standard_False;
myUIsoIsDeg = Standard_False;
myVIsoIsDeg = Standard_False;
}
//=============================================================================
Extrema_FuncExtPS::Extrema_FuncExtPS (const gp_Pnt& P,
const Adaptor3d_Surface& S)
{
myP = P;
myS = (Adaptor3d_SurfacePtr)&S;
myUIsoIsDeg = Standard_False;
myVIsoIsDeg = Standard_False;
GeomAbs_SurfaceType aSType = S.GetType();
if(aSType == GeomAbs_BezierSurface ||
aSType == GeomAbs_BSplineSurface) {
Standard_Real u1, u2, v1, v2;
Standard_Real tol = Precision::Confusion();
u1 = S.FirstUParameter();
u2 = S.LastUParameter();
v1 = S.FirstVParameter();
v2 = S.LastVParameter();
myUIsoIsDeg = IsoIsDeg(S, u1, GeomAbs_IsoU, 0., tol) ||
IsoIsDeg(S, u2, GeomAbs_IsoU, 0., tol);
myVIsoIsDeg = IsoIsDeg(S, v1, GeomAbs_IsoV, 0., tol) ||
IsoIsDeg(S, v2, GeomAbs_IsoV, 0., tol);
}
myPinit = Standard_True;
mySinit = Standard_True;
}
//=============================================================================
void Extrema_FuncExtPS::Initialize(const Adaptor3d_Surface& S)
{
myS = (Adaptor3d_SurfacePtr)&S;
myUIsoIsDeg = Standard_False;
myVIsoIsDeg = Standard_False;
GeomAbs_SurfaceType aSType = S.GetType();
if(aSType == GeomAbs_BezierSurface ||
aSType == GeomAbs_BSplineSurface) {
Standard_Real u1, u2, v1, v2;
Standard_Real tol = Precision::Confusion();
u1 = S.FirstUParameter();
u2 = S.LastUParameter();
v1 = S.FirstVParameter();
v2 = S.LastVParameter();
myUIsoIsDeg = IsoIsDeg(S, u1, GeomAbs_IsoU, 0., tol) ||
IsoIsDeg(S, u2, GeomAbs_IsoU, 0., tol);
myVIsoIsDeg = IsoIsDeg(S, v1, GeomAbs_IsoV, 0., tol) ||
IsoIsDeg(S, v2, GeomAbs_IsoV, 0., tol);
}
mySinit = Standard_True;
myPoint.Clear();
mySqDist.Clear();
}
//=============================================================================
void Extrema_FuncExtPS::SetPoint(const gp_Pnt& P)
{
myP = P;
myPinit = Standard_True;
myPoint.Clear();
mySqDist.Clear();
}
//=============================================================================
//=============================================================================
Standard_Integer Extrema_FuncExtPS::NbVariables () const { return 2;}
//=============================================================================
Standard_Integer Extrema_FuncExtPS::NbEquations () const { return 2;}
//=============================================================================
Standard_Boolean Extrema_FuncExtPS::Value (const math_Vector& UV,
math_Vector& F)
{
if (!myPinit || !mySinit) Standard_TypeMismatch::Raise();
myU = UV(1);
myV = UV(2);
gp_Vec Dus, Dvs;
myS->D1(myU,myV,myPs,Dus,Dvs);
gp_Vec PPs (myP,myPs);
// EAP
if(myVIsoIsDeg)
{
Standard_Real DusMod = Dus.Magnitude();
if (DusMod>gp::Resolution() && DusMod<1.)
Dus.Multiply(1/DusMod);
}
if (myUIsoIsDeg) {
Standard_Real DvsMod = Dvs.Magnitude();
if (DvsMod>gp::Resolution() && DvsMod<1.)
Dvs.Multiply(1/DvsMod);
}
F(1) = PPs.Dot(Dus);
F(2) = PPs.Dot(Dvs);
return Standard_True;
}
//=============================================================================
Standard_Boolean Extrema_FuncExtPS::Derivatives (const math_Vector& UV,
math_Matrix& Df)
{
math_Vector F(1,2);
return Values(UV,F,Df);
}
//=============================================================================
Standard_Boolean Extrema_FuncExtPS::Values (const math_Vector& UV,
math_Vector& F,
math_Matrix& Df)
{
if (!myPinit || !mySinit) Standard_TypeMismatch::Raise();
myU = UV(1);
myV = UV(2);
gp_Vec Dus, Dvs, Duus, Dvvs, Duvs;
myS->D2(myU,myV,myPs,Dus,Dvs,Duus,Dvvs,Duvs);
gp_Vec PPs (myP,myPs);
// EAP
// Df(1,1) = Dus.SquareMagnitude() + PPs.Dot(Duus);
// Df(1,2) = Dvs.Dot(Dus) + PPs.Dot(Duvs);
// Df(2,1) = Df(1,2);
// Df(2,2) = Dvs.SquareMagnitude() + PPs.Dot(Dvvs);
// 25/03/02 akm : (OCC231) Further normalization of derivatives for surfaces
// with singularities will hence be performed only when modulus
// becomes less than 1.0. Thus the continuity will be kept,
// and normalization will be switched off 'far' from singularities.
// 1. V iso
Standard_Real DusMod2 = Dus.SquareMagnitude();
if (myVIsoIsDeg)
{
Standard_Real DusMod = Sqrt(DusMod2);
if (DusMod2>gp::Resolution() && DusMod2<1.)
{
Dus.Multiply(1/DusMod);
Df(1,1) = DusMod2 + PPs.Dot( (Duus*DusMod - Dus*(Dus.Dot(Duus)/DusMod)) / DusMod2 );
Df(1,2) = Dvs.Dot(Dus) + PPs.Dot( (Duvs*DusMod-Dus*(Dus.Dot(Duvs)/DusMod)) / DusMod2 );
}
else {
Df(1,1) = DusMod2 + PPs.Dot(Duus);
Df(1,2) = Dvs.Dot(Dus) + PPs.Dot(Duvs);
}
}
else {
Df(1,1) = DusMod2 + PPs.Dot(Duus);
Df(1,2) = Dvs.Dot(Dus) + PPs.Dot(Duvs);
}
// 2. U iso
Standard_Real DvsMod2 = Dvs.SquareMagnitude();
if (myUIsoIsDeg)
{
Standard_Real DvsMod = Sqrt(DvsMod2);
if (DvsMod2>gp::Resolution() && DvsMod2<1.)
{
Dvs.Multiply(1/DvsMod);
Df(2,1) = Dvs.Dot(Dus) + PPs.Dot( (Duvs*DvsMod-Dvs*(Dvs.Dot(Duvs)/DvsMod)) / DvsMod2 );
Df(2,2) = DvsMod2 + PPs.Dot( (Duus*DvsMod - Dus*(Dus.Dot(Duus)/DvsMod)) / DvsMod2 );
}
else {
Df(2,1) = Dvs.Dot(Dus) + PPs.Dot(Duvs);
Df(2,2) = DvsMod2 + PPs.Dot(Dvvs);
}
}
else {
Df(2,1) = Dvs.Dot(Dus) + PPs.Dot(Duvs);
Df(2,2) = DvsMod2 + PPs.Dot(Dvvs);
}
F(1) = PPs.Dot(Dus);
F(2) = PPs.Dot(Dvs);
return Standard_True;
}
//=============================================================================
Standard_Integer Extrema_FuncExtPS::GetStateNumber ()
{
if (!myPinit || !mySinit) Standard_TypeMismatch::Raise();
mySqDist.Append(myPs.SquareDistance(myP));
myPoint.Append(Extrema_POnSurf(myU,myV,myPs));
return 0;
}
//=============================================================================
Standard_Integer Extrema_FuncExtPS::NbExt () const
{
return mySqDist.Length();
}
//=============================================================================
Standard_Real Extrema_FuncExtPS::SquareDistance (const Standard_Integer N) const
{
if (!myPinit || !mySinit) Standard_TypeMismatch::Raise();
return mySqDist.Value(N);
}
//=============================================================================
Extrema_POnSurf Extrema_FuncExtPS::Point (const Standard_Integer N) const
{
if (!myPinit || !mySinit) Standard_TypeMismatch::Raise();
return myPoint.Value(N);
}
//=============================================================================
// Modified by skv - Thu Sep 30 15:21:07 2004 OCC593 Begin
Standard_Boolean Extrema_FuncExtPS::HasDegIso() const
{
return myUIsoIsDeg || myVIsoIsDeg;
}
// Modified by skv - Thu Sep 30 15:21:07 2004 OCC593 End
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