Self-Intersection test for tyPush

[Findus]

Just in case you ever get around to this: It might be better to have this as a separate modifier just pushing the surface out or in to a given distance for any surface point "seeing" another surface point along its normal. I guesss this should not be iterative (only use the original positions for each frame) depending on the resulting effect.

I tried to do achieve something similar with tyConform and a copy of the object, but couldn't get it to work.