Utility function to generate OCC shape triangulation -> always use same parameters

libsrc/occ/occ_utils.cpp

@@ -1,6 +1,8 @@
 #include <Bnd_Box.hxx>
 #include <BRepBndLib.hxx>
 #include <BRep_TVertex.hxx>
+#include <BRepMesh_IncrementalMesh.hxx>
+#include <BRepTools.hxx>
 
 #include "occ_utils.hpp"
 
@@ -55,4 +57,24 @@ namespace netgen
 #endif
         return {occ2ng(bb.CornerMin()), occ2ng(bb.CornerMax())};
     }
+
+    Standard_Integer BuildTriangulation( const TopoDS_Shape & shape )
+    {
+       BRepTools::Clean (shape);
+       double deflection = 0.01;
+
+       // https://dev.opencascade.org/doc/overview/html/occt_user_guides__mesh.html
+       // from Standard_Boolean meshing_imeshtools_parameters()
+       IMeshTools_Parameters aMeshParams;
+       aMeshParams.Deflection               = 0.01;
+       aMeshParams.Angle                    = 0.5;
+       aMeshParams.Relative                 = Standard_False;
+       aMeshParams.InParallel               = Standard_True;
+       aMeshParams.MinSize                  = Precision::Confusion();
+       aMeshParams.InternalVerticesMode     = Standard_True;
+       aMeshParams.ControlSurfaceDeflection = Standard_True;
+
+       BRepMesh_IncrementalMesh aMesher (shape, aMeshParams);
+       return  aMesher.GetStatusFlags();
+    }
 }

libsrc/occ/occ_utils.hpp

@@ -76,6 +76,8 @@ namespace netgen
       bool opposite_direction;
     };
 
+    Standard_Integer BuildTriangulation( const TopoDS_Shape & shape );
+
 
     class MyExplorer
     {

libsrc/occ/occgenmesh.cpp

@@ -11,7 +11,6 @@
 #include <BRepGProp.hxx>
 #include <BRepLProp_CLProps.hxx>
 #include <BRepLProp_SLProps.hxx>
-#include <BRepMesh_IncrementalMesh.hxx>
 #include <BRepTools.hxx>
 #include <GProp_GProps.hxx>
 #include <Quantity_Color.hxx>
@@ -654,6 +653,7 @@ namespace netgen
 
         int nfaces = geom.fmap.Extent();
 
+        BuildTriangulation(geom.shape);
         for (int i = 1; i <= nfaces && !multithread.terminate; i++)
           {
             multithread.percent = 100 * (i-1)/double(nfaces);
@@ -663,29 +663,6 @@ namespace netgen
             Handle(Geom_Surface) surf = BRep_Tool::Surface (face);
             Handle(Poly_Triangulation) triangulation = BRep_Tool::Triangulation (face, loc);
 
-            if (triangulation.IsNull())
-              {
-                BRepTools::Clean (geom.shape);
-                // BRepMesh_IncrementalMesh (geom.shape, 0.01, true);
-
-                // https://dev.opencascade.org/doc/overview/html/occt_user_guides__mesh.html
-                IMeshTools_Parameters aMeshParams;
-                aMeshParams.Deflection               = 0.01;
-                aMeshParams.Angle                    = 0.5;
-                aMeshParams.Relative                 = Standard_False;
-                aMeshParams.InParallel               = Standard_True;
-                aMeshParams.MinSize                  = Precision::Confusion();
-                aMeshParams.InternalVerticesMode     = Standard_True;
-                aMeshParams.ControlSurfaceDeflection = Standard_True;
-                
-                BRepMesh_IncrementalMesh aMesher (geom.shape, aMeshParams);
-                const Standard_Integer aStatus = aMesher.GetStatusFlags();
-                if (aStatus != 0)
-                  cout << "BRepMesh_IncrementalMesh.status = " << aStatus << endl;
-                
-                triangulation = BRep_Tool::Triangulation (face, loc);                
-              }
-            
             if(triangulation.IsNull())
               {
                 if (geom.shape.Infinite())

libsrc/occ/occgeom.cpp

@@ -23,7 +23,6 @@
 #include <BRepExtrema_DistShapeShape.hxx>
 #include <BRepGProp.hxx>
 #include <BRepLib.hxx>
-#include <BRepMesh_IncrementalMesh.hxx>
 #include <BRepOffsetAPI_Sewing.hxx>
 #include <BRepTools.hxx>
 #include <IGESCAFControl_Reader.hxx>
@@ -1387,12 +1386,9 @@ namespace netgen
 
    void OCCGeometry :: BuildVisualizationMesh (double deflection)
    {
-      cout << "Preparing visualization (deflection = " << deflection << ") ... " << flush;
+      // cout << IM(5) << "Preparing visualization (deflection = " << deflection << ") ... " << flush;
-
+      BuildTriangulation(shape);
-      BRepTools::Clean (shape);
+      // cout << IM(5) << "done" << endl;
-      // BRepMesh_IncrementalMesh::
-      BRepMesh_IncrementalMesh (shape, deflection, true);
-      cout << "done" << endl;
    }
 
 

libsrc/occ/python_occ_shapes.cpp

@@ -9,6 +9,7 @@
 #include <meshing.hpp>
 
 #include "occgeom.hpp"
+#include "occ_utils.hpp"
 
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
@@ -32,7 +33,6 @@
 #include <BRepGProp.hxx>
 #include <BRepLProp_SLProps.hxx>
 #include <BRepLib.hxx>
-#include <BRepMesh_IncrementalMesh.hxx>
 #include <BRepOffsetAPI_MakeOffset.hxx>
 #include <BRepOffsetAPI_MakePipe.hxx>
 #include <BRepOffsetAPI_MakePipeShell.hxx>
@@ -45,7 +45,6 @@
 #include <BRepPrimAPI_MakePrism.hxx>
 #include <BRepPrimAPI_MakeRevol.hxx>
 #include <BRepPrimAPI_MakeSphere.hxx>
-#include <BRepTools.hxx>
 #include <GCE2d_MakeArcOfCircle.hxx>
 #include <GCE2d_MakeCircle.hxx>
 #include <GCE2d_MakeSegment.hxx>
@@ -1150,9 +1149,7 @@ DLL_HEADER void ExportNgOCCShapes(py::module &m)
     
     .def("MakeTriangulation", [](const TopoDS_Shape & shape)
          {
-           BRepTools::Clean (shape);
+           BuildTriangulation(shape);
-           double deflection = 0.01;
-           BRepMesh_IncrementalMesh (shape, deflection, true);
          })
 
 
@@ -1181,12 +1178,6 @@ DLL_HEADER void ExportNgOCCShapes(py::module &m)
                throw NgException ("Triangulation: shape is not a face");
              }
 
-           /*
-           BRepTools::Clean (shape);
-           double deflection = 0.01;
-           BRepMesh_IncrementalMesh (shape, deflection, true);
-           */
-
            Handle(Geom_Surface) surf = BRep_Tool::Surface (face);
 
            TopLoc_Location loc;
@@ -1194,9 +1185,7 @@ DLL_HEADER void ExportNgOCCShapes(py::module &m)
            
            if (triangulation.IsNull())
              {
-               BRepTools::Clean (shape);
+               BuildTriangulation(shape);
-               double deflection = 0.01;
-               BRepMesh_IncrementalMesh (shape, deflection, true);
                triangulation = BRep_Tool::Triangulation (face, loc);               
              }
            // throw Exception("Don't have a triangulation, call 'MakeTriangulation' first");
@@ -1217,30 +1206,9 @@ DLL_HEADER void ExportNgOCCShapes(py::module &m)
          })
     .def("_webgui_data", [](const TopoDS_Shape & shape)
          {
-           BRepTools::Clean (shape);
+           auto status = BuildTriangulation(shape);
-           double deflection = 0.01;
-
-           // BRepMesh_IncrementalMesh mesher(shape, deflection,Standard_True, 0.01, true);
-           // mesher.Perform();
-
-
-           // https://dev.opencascade.org/doc/overview/html/occt_user_guides__mesh.html
-           // from Standard_Boolean meshing_imeshtools_parameters()
-           IMeshTools_Parameters aMeshParams;
-           aMeshParams.Deflection               = 0.01;
-           aMeshParams.Angle                    = 0.5;
-           aMeshParams.Relative                 = Standard_False;
-           aMeshParams.InParallel               = Standard_True;
-           aMeshParams.MinSize                  = Precision::Confusion();
-           aMeshParams.InternalVerticesMode     = Standard_True;
-           aMeshParams.ControlSurfaceDeflection = Standard_True;
-           
-           BRepMesh_IncrementalMesh aMesher (shape, aMeshParams);
-           const Standard_Integer aStatus = aMesher.GetStatusFlags();
            // cout << "status = " << aStatus << endl;
            
-           // triangulation = BRep_Tool::Triangulation (face, loc);
-
            std::vector<double> p[3];
            std::vector<double> n[3];
            py::list names, colors, solid_names;