first post, difficult question (for me). I got a copy of Andy's great shader book, which works fine for me (examples...). I would like to write a shader, which takes the world position of each vertex and saves that one as a color (edges and polys get interpolated colors). Until here this is actually nothing else than a world space shader (which I could get working). BUT the color of each vertex should only be taken at the first frame of an animation, so the vertex world colors would move with the mesh - not change (like baking the vertex position as colors into a map). Is it possible to look back in time with a state stuct?
I have seen this working in RenderMan and thought this could be an interesting thing to implement.
Thanks for helping