Hello,
I encountered an issue where surface meshing fails (returns `1`) when the given solid geometry contains bezier curves with congruent control points. The output mesh is not watertight at the area where the congruent control points are located. A complete example for reproduction is attached. However, this erroneous behavior can also be encountered with many different geometries containing congruent bezier control points.
Here is the code (OCCT 7.9, Netgen 6.2.2604):
const char* infile = “C:\\temp\\seg.brep”;
TopoDS_Shape shape;
BRepTools::Read(shape, infile, BRep_Builder());
auto occgeom = std::make_shared < netgen::OCCGeometry > (shape);netgen::MeshingParameters mp;
mp.perfstepsend = netgen::MESHCONST_MESHSURFACE;
mp.minh = 1;
mp.maxh = 20;auto mesh = std::make_shared < netgen::Mesh > ();
mesh->SetGeometry(occgeom);
auto result = occgeom->GenerateMesh(mesh, mp);
Here is a schematic view of the given rotational symmetric geometry. The outer contour is a bezier curve of degree 4 with 5 control points where the first 3 control points are congruent:
Geometry failing to mesh:
seg.brep (116.2 KB)
For comparison the following geometry has no congruent control points and meshing runs successfully:
seg_okay.brep (77.7 KB)
It would be great, if this issue can be fixed.
Best regards,
Matthias