src/OCC2VTK/OCC2VTK_Tools.cxx

   1 // Copyright (C) 2007-2014  CEA/DEN, EDF R&D, OPEN CASCADE
   2 //
   3 // This library is free software; you can redistribute it and/or
   4 // modify it under the terms of the GNU Lesser General Public
   5 // License as published by the Free Software Foundation; either
   6 // version 2.1 of the License, or (at your option) any later version.
   7 //
   8 // This library is distributed in the hope that it will be useful,
   9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 // Lesser General Public License for more details.
  12 //
  13 // You should have received a copy of the GNU Lesser General Public
  14 // License along with this library; if not, write to the Free Software
  15 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  16 //
  17 // See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
  18 //
  19
  20 #include "OCC2VTK_Tools.h"
  21
  22 #include "GEOM_VertexSource.h"
  23 #include "GEOM_EdgeSource.h"
  24 #include "GEOM_WireframeFace.h"
  25 #include "GEOM_ShadingFace.h"
  26
  27 #include <Bnd_Box.hxx>
  28 #include <BRep_Tool.hxx>
  29 #include <BRepTools.hxx>
  30
  31 #include <BRepBndLib.hxx>
  32 #include <BRepMesh_IncrementalMesh.hxx>
  33 #include <Poly_Triangulation.hxx>
  34 #include <TopExp_Explorer.hxx>
  35 #include <TopoDS.hxx>
  36 #include <TopTools_ListOfShape.hxx>
  37
  38 #define MAX2(X, Y)    (Abs(X) > Abs(Y) ? Abs(X) : Abs(Y))
  39 #define MAX3(X, Y, Z) (MAX2(MAX2(X,Y), Z))
  40
  41
  42 #define DEFAULT_DEFLECTION 0.001
  43
  44 namespace GEOM
  45 {
  46   void MeshShape(const TopoDS_Shape theShape,
  47                  float& theDeflection,
  48                  bool theForced ) {
  49
  50     Standard_Real aDeflection = theDeflection <= 0 ? DEFAULT_DEFLECTION : theDeflection;
  51
  52     //If deflection <= 0, than return default deflection
  53     if(theDeflection <= 0)
  54       theDeflection = aDeflection;
  55
  56     // Is shape triangulated?
  57     Standard_Boolean alreadymeshed = Standard_True;
  58     TopExp_Explorer ex;
  59     TopLoc_Location aLoc;
  60     for (ex.Init(theShape, TopAbs_FACE); ex.More(); ex.Next()) {
  61       const TopoDS_Face& aFace = TopoDS::Face(ex.Current());
  62       Handle(Poly_Triangulation) aPoly = BRep_Tool::Triangulation(aFace,aLoc);
  63       if(aPoly.IsNull()) {
  64         alreadymeshed = Standard_False;
  65         break;
  66       }
  67     }
  68
  69     if(!alreadymeshed || theForced) {
  70       Bnd_Box B;
  71       BRepBndLib::Add(theShape, B);
  72       if ( B.IsVoid() )
  73         return; // NPAL15983 (Bug when displaying empty groups)
  74       Standard_Real aXmin, aYmin, aZmin, aXmax, aYmax, aZmax;
  75       B.Get(aXmin, aYmin, aZmin, aXmax, aYmax, aZmax);
  76
  77       // This magic line comes from Prs3d_ShadedShape.gxx in OCCT
  78       aDeflection = MAX3(aXmax-aXmin, aYmax-aYmin, aZmax-aZmin) * aDeflection * 4;
  79
  80       //Clean triangulation before compute incremental mesh
  81       BRepTools::Clean(theShape);
  82
  83       //Compute triangulation
  84       BRepMesh_IncrementalMesh MESH(theShape,aDeflection);
  85     }
  86   }
  87
  88   void SetShape(const TopoDS_Shape& theShape,
  89                 const TopTools_IndexedDataMapOfShapeListOfShape& theEdgeMap,
  90                 bool theIsVector,
  91                 GEOM_VertexSource* theStandaloneVertexSource,
  92                 GEOM_EdgeSource* theIsolatedEdgeSource,
  93                 GEOM_EdgeSource* theOneFaceEdgeSource,
  94                 GEOM_EdgeSource* theSharedEdgeSource,
  95                 GEOM_WireframeFace* theWireframeFaceSource,
  96                 GEOM_ShadingFace* theShadingFaceSource)
  97   {
  98     if (theShape.ShapeType() == TopAbs_COMPOUND) {
  99       TopoDS_Iterator anItr(theShape);
 100       for (; anItr.More(); anItr.Next()) {
 101         SetShape(anItr.Value(),theEdgeMap,theIsVector,
 102                  theStandaloneVertexSource,
 103                  theIsolatedEdgeSource,
 104                  theOneFaceEdgeSource,
 105                  theSharedEdgeSource,
 106                  theWireframeFaceSource,
 107                  theShadingFaceSource);
 108       }
 109     }
 110
 111     switch (theShape.ShapeType()) {
 112       case TopAbs_WIRE: {
 113         TopExp_Explorer anEdgeExp(theShape,TopAbs_EDGE);
 114         for (; anEdgeExp.More(); anEdgeExp.Next()){
 115           const TopoDS_Edge& anEdge = TopoDS::Edge(anEdgeExp.Current());
 116           if (!BRep_Tool::Degenerated(anEdge))
 117             theIsolatedEdgeSource->AddEdge(anEdge,theIsVector);
 118         }
 119         break;
 120       }
 121       case TopAbs_EDGE: {
 122         const TopoDS_Edge& anEdge = TopoDS::Edge(theShape);
 123         if (!BRep_Tool::Degenerated(anEdge))
 124           theIsolatedEdgeSource->AddEdge(anEdge,theIsVector);
 125         break;
 126       }
 127       case TopAbs_VERTEX: {
 128         if ( theStandaloneVertexSource ) {
 129           const TopoDS_Vertex& aVertex = TopoDS::Vertex(theShape);
 130           theStandaloneVertexSource->AddVertex(aVertex);
 131         }
 132         break;
 133       }
 134       default: {
 135         TopExp_Explorer aFaceExp (theShape,TopAbs_FACE);
 136         for(; aFaceExp.More(); aFaceExp.Next()) {
 137           const TopoDS_Face& aFace = TopoDS::Face(aFaceExp.Current());
 138           theWireframeFaceSource->AddFace(aFace);
 139           theShadingFaceSource->AddFace(aFace);
 140           TopExp_Explorer anEdgeExp(aFaceExp.Current(), TopAbs_EDGE);
 141           for(; anEdgeExp.More(); anEdgeExp.Next()) {
 142             const TopoDS_Edge& anEdge = TopoDS::Edge(anEdgeExp.Current());
 143             if(!BRep_Tool::Degenerated(anEdge)){
 144               // compute the number of faces
 145               int aNbOfFaces = theEdgeMap.FindFromKey(anEdge).Extent();
 146               switch(aNbOfFaces){
 147               case 0:  // isolated edge
 148                 theIsolatedEdgeSource->AddEdge(anEdge,theIsVector);
 149                 break;
 150               case 1:  // edge in only one face
 151                 theOneFaceEdgeSource->AddEdge(anEdge,theIsVector);
 152                 break;
 153               default: // edge shared by at least two faces
 154                 theSharedEdgeSource->AddEdge(anEdge,theIsVector);
 155               }
 156             }
 157           }
 158         }
 159       }
 160     }
 161   }
 162 }