Shading problem with vertices weld

Hi all,

I encountered a problem with vertices weld. In GH i build a wall with clean mesh geometry. It’s build using cuts at the window sides and deleting the window openings. This way it’s optimized for export to Unreal.
Thing is that all the vertices are unwelded. When doing a weld vertices operation I get shading problems which also exports to Blender/3DsMax trough FBX and is visible in my V-Ray renders. When I export the unwelded version to 3DsMax trough FBX its possible to weld the vertices there. 3DsMax doesn’t give these shading problems. Is this a bug in Rhino 6, or am I doing something wrong?

Greetings, Jakob.

Hi @pixual, you would ideally pass a face normal angle tolerance for determining which edges to weld. So the edges between flat areas would be welded and the 90 degree edges around the window holes left unwelded. In RhinoCommon calling Mesh.Weld(double angleToleranceRadians) with a tolerance around 0.17 (it’s about 10 degrees) would do that.