Triangle mesh winding of facets from the Inventor API

[jeremy.herbert]

Hi, 

Just a quick one which I can't seem to find the answer for (perhaps I am using the wrong keywords?). When you generate facets of a SurfaceBody using the Inventor API, are the triangles in the mesh guaranteed to have a particular winding? ie will they always be listed in a specific rotation with respect to the triangle normal?

Also, are the vertex normals generated always guaranteed to be outward facing by default? I understand this is the convention for meshes in general, but I'm not sure if Inventor does it.

Thanks!

[ekinsb]

Inventor follows the standard conventions.

[jeremy.herbert]

so does that mean normals always outward, vertex winding counterclockwise?

[ekinsb · Accepted solution]

Yes, normals will always point out when the mesh was generated from a solid.  If the mesh was generated from a surface, there isn't an "out" direction but it will be arbitrary and all of triangles in the mesh will be consistent.  The vertex winding is also consistent and is counterclockwise.

[jeremy.herbert]

Perfect. Thank you!