Apply a subdivision scheme to an existing mesh.

Input parameters:

1. Ms → Mesh to subdivide.
2. St → Number of subdivision steps. Each additional step approximately quadruples the number of facets in a mesh.
3. Cr → Retain the unwelded creases in the input mesh.
   •  True → Retain
   • False → Ignore
4. Co → Specify the angle, above which convex corners of the input mesh boundary will be retained.

Output parameters:

1. Ms → Subdivided mesh.