Hi Clesage,

what im looking for is more of a guideline on how to achieve the end results, (calculate first the contact points…then the offset of such point so that the surface stay on top…etc) .

Yesterday i figured how to keep the poly on top of the base surface calculating an offset for my geometry, it was a simple distances comparison, taking advantage of the point on poly constraint i projected

a locator from the edge of my poly to the surface, then i calculated the radius and distance between these 3 points , and as the contact point goes to 0 i could extrapolate an offset.

Now i have 1 point only that keeps my surface on top of the other… the tricky part now is that i need to find a way to rotate such surface… and then i would need to also find a way to interpolate between all these points as my geometry rolls on the surface…all these things i haven’t quite figure out how to do it yet.

once i can do it on a round surface (convex ) , then ill also have to figure how to do it on a concave one (then i have no clue on how to interpolate my position/rotation based on two points contact…)

I am wondering if i would need some sort of weight blender type of thing, based on the distances of all these points…mh, if is not clear maybe ill try doing some sketches.

Again, if you have any hints would be appreciated .

thanks

-a