Here is an animation of membrane bunching I have been working on with help from Arthur. The membrane is suspended from 4 outer hanging points and 1 central. Triangulating springs are added to the mesh to force it to retain its shape and bunch like a real fabric. In order to achieve the complex folding that occurs in fabrics, the vertical unary force is not applied universally to all points, but is rather applied to only the paths within the fabric along which the majority of the load passes. This was calculated through earlier research. When the fabric first drops at the beginning of the video these force paths are visible.