OBJ

MESHFREE supports Wavefront .OBJ surface meshes consisting of semi-planar polygonal facets. The boundary elements of the mesh are triangles or convex polygons with up to six vertices. Arbitrary shaped NURBS-surfaces are not supported and are silently ignored while reading the OBJ file. MESHFREE internally converts the polygonal facets into triangles by the simple ear clipping algorithm. Beware that concave polygons may result in triangles with a reverted normal vector pointing in a reverse direction. There is no check for concave polygons implemented. OBJ files may also contain vertex normal vectors and vertex textures per vertex for a smooth shading with graphic visualizers (see http://paulbourke.net/dataformats/obj]. This additional information is ignored. The facet normal is the normal of the triangle in clockwise orientation (Right Hand Rule) MESHFREE derives the alias name of the surface entity in AliasForGeometryItems from the given group in the .obj file. Group names for faces and surfaces can be added in .obj file in the following way. If no group is given the alias name is taken from the file name.