occt/src/AppParCurves/AppParCurves_Variational_9.gxx

// Created on: 1999-02-19
// Created by: Sergey KHROMOV
// Copyright (c) 1999-1999 Matra Datavision
// Copyright (c) 1999-2012 OPEN CASCADE SAS
//
// The content of this file is subject to the Open CASCADE Technology Public
// License Version 6.5 (the "License"). You may not use the content of this file
// except in compliance with the License. Please obtain a copy of the License
// at http://www.opencascade.org and read it completely before using this file.
//
// The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
// main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
//
// The Original Code and all software distributed under the License is
// distributed on an "AS IS" basis, without warranty of any kind, and the
// Initial Developer hereby disclaims all such warranties, including without
// limitation, any warranties of merchantability, fitness for a particular
// purpose or non-infringement. Please see the License for the specific terms
// and conditions governing the rights and limitations under the License.


static Standard_Boolean NotParallel(gp_Vec& T, gp_Vec& V)
{
  V = T;
  V.SetX(V.X() + 1.);
  if (V.CrossMagnitude(T) > 1.e-12)
    return Standard_True;
  V.SetY(V.Y() + 1.);
  if (V.CrossMagnitude(T) > 1.e-12)
    return Standard_True;
  V.SetZ(V.Z() + 1.);
  if (V.CrossMagnitude(T) > 1.e-12)
    return Standard_True;
  return Standard_False;
}

 Standard_Boolean AppParCurves_Variational::InitTthetaF(const Standard_Integer ndimen,
							const AppParCurves_Constraint typcon,
							const Standard_Integer begin,
							const Standard_Integer jndex)
{
  if ((ndimen < 2)||(ndimen >3))
    return Standard_False;
  gp_Vec T, V;
  gp_Vec theta1, theta2;
  gp_Vec F;
  Standard_Real XX, XY, YY, XZ, YZ, ZZ;

  if ((typcon == AppParCurves_TangencyPoint)||(typcon == AppParCurves_CurvaturePoint))
    {
      T.SetX(myTabConstraints->Value(jndex));
      T.SetY(myTabConstraints->Value(jndex + 1));
      if (ndimen == 3)
	T.SetZ(myTabConstraints->Value(jndex + 2));
      else
	T.SetZ(0.);
      if (ndimen == 2)
	{
	  V.SetX(0.);
	  V.SetY(0.);
	  V.SetZ(1.);
	}
      if (ndimen == 3)
	if (!NotParallel(T, V))
	  return Standard_False;
      theta1 = V ^ T;
      theta1.Normalize();
      myTtheta->SetValue(begin, theta1.X());
      myTtheta->SetValue(begin + 1, theta1.Y());
      if (ndimen == 3)
	{
	  theta2 = T ^ theta1;
	  theta2.Normalize();
	  myTtheta->SetValue(begin + 2, theta1.Z());
	  myTtheta->SetValue(begin + 3, theta2.X());
	  myTtheta->SetValue(begin + 4, theta2.Y());
	  myTtheta->SetValue(begin + 5, theta2.Z());
	}
      
      // Calculation of myTfthet
      if (typcon == AppParCurves_CurvaturePoint)
	{
	  XX = Pow(T.X(), 2);
	  XY = T.X() * T.Y();
	  YY = Pow(T.Y(), 2);
	  if (ndimen == 2) 
	    {
	      F.SetX(YY * theta1.X() - XY * theta1.Y());
	      F.SetY(XX * theta1.Y() - XY * theta1.X());
	      myTfthet->SetValue(begin, F.X());
	      myTfthet->SetValue(begin + 1, F.Y());
	    }
	  if (ndimen == 3)
	    {
	      XZ = T.X() * T.Z();
	      YZ = T.Y() * T.Z();
	      ZZ = Pow(T.Z(), 2);
	      
	      F.SetX((ZZ + YY) * theta1.X() - XY * theta1.Y() - XZ * theta1.Z());
	      F.SetY((XX + ZZ) * theta1.Y() - XY * theta1.X() - YZ * theta1.Z());
	      F.SetZ((XX + YY) * theta1.Z() - XZ * theta1.X() - YZ * theta1.Y());
	      myTfthet->SetValue(begin, F.X());
	      myTfthet->SetValue(begin + 1, F.Y());
	      myTfthet->SetValue(begin + 2, F.Z());
	      F.SetX((ZZ + YY) * theta2.X() - XY * theta2.Y() - XZ * theta2.Z());
	      F.SetY((XX + ZZ) * theta2.Y() - XY * theta2.X() - YZ * theta2.Z());
	      F.SetZ((XX + YY) * theta2.Z() - XZ * theta2.X() - YZ * theta2.Y());
	      myTfthet->SetValue(begin + 3, F.X());
	      myTfthet->SetValue(begin + 4, F.Y());
	      myTfthet->SetValue(begin + 5, F.Z());
	    }
	}
    }
  return Standard_True;
}