I have a grid (a) and a simple quad (b), both of which live in the XY-plane. I’d like to efficiently interpolate and copy a’s Cd attribute to each point of b. This can be done in VEX, as shown in c. However, if the grid a has a very high resolution, or if b consists of more than just 2 triangles, things get slow.

Since this is essentially a rasterization problem, I wonder if I could somehow do this on the GPU to make it fast. Is this a feasible idea?

there's an opencl sop node in Houdini, but I have no experience with it.
here's a master class about opencl vs vex

https://vimeo.com/241568199 [vimeo.com]