Rotated Point Displacement Vector

[anonymous_user_71b31e23]

I have a mesh which is bouncing and rotating down on a slope. I try to calculate the displacement vector of the last impact point. I saved the last impact point and the object transform when the last impact happend. Obviously I know the transfrom when I want to calculate the displacement vector. How can I calculate the displacement vector from these data?(Do I need anything else?)

PS: I attached an “awesome programmer art” to visualize the problem

[LogierJan]

You can calculate the vector between point A (impact point) and point B (current point) by substracting point A from B.

[anonymous_user_71b31e23]

I dont know the point B though, just point A, the original mesh transform, and the current mesh transform (which is not equal with the point B).

[anonymous_user_71b31e23]

I solved the problem, in case you wondering this is the math.