Let's say there's 2 rendering image A and B from same scene and same camera, how can I do this by compositor or script?
- compare image A and B
- turn the same part into an alpha and export to image C
I mark the boundary with a line for easy understanding, the real image don't have the boundary line. Image C's boundary is same to the image B' (crop B's blank area)
It might be too complicated to understand, let me know if you had any question.