On this page you can download two 3D sphere models which we have descriptively called ‘spherical rind 3D shapes’.
Both 3D models are very easy to model by combining Blender and TopMod software. In Blender software, we modeled a plain sphere to which we applied the Simple Deform modifier (Twist, z axis). The 3D sphere model thus obtained was imported into TopMod software where we selected and deleted certain series of faces. This process could have been done in Blender software as well, but at that time, it was TopMod software that we were delighted with, so we modeled such 3D models mainly in it. The 3D model obtained in the way described was then exported (.obj file format) to Rhino 3D software where we transformed the polygonal mesh into a NURBS 3D model using T-splines plug-in. It may seem that we used a lot of software programs, but the whole process took less than 5 minutes.
Topmod + Rhino 3D and T-splines plug-in (conversion to NURBS 3D surfaces)
Surface 3D model - .igs (Initial Graphics Exchange Specification)
Geometry: Mesh - Quads and triangles; Mesh topology supports multiple subdivisions; 3D model without texture and materials