Not every polygonal object is suitable for dynamics. Neither for Bullet, nor for the Cloth-Room.

Rule number one: Polygons must not penetrate each other.

It is not always easy to see whether a polygonal object fulfills this condition. Objects that are to be calculated physically correct (and are not rigid bodies) should be specially made for this purpose (saying this, hair is 99% out of the game).

Not only should the main requirement be met (no penetration), but the object should also consist of polygons that are as evenly sized and equally distributed as possible. But please only as many as absolutely necessary!

Sure: With a lot of patience and time, a lot of knowledge and a lot of testing you can achieve that you can use objects that are not actually useful for dynamics. Now and then, at least, and mostly not reproducible. And: The experiences made and results worked out usually cannot simply be projected onto the next object.

The best results (when using Poser) I have achieved so far with the Cloth-Room. If you follow the rules there, it works quickly and without complaint.

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