I've been watching the series start to finish and have gotten to the lighting portion of the series. I've been finding this part the most difficult part to follow, however, and can't seem to intuit how the multigrid lighting technique actually works.
I feel like for someone with prior knowledge of light equations / transports it might be intuitive, but I feel totally lost!
I understand the performance motivation behind the multigrid approach, i.e. sampling from lower res textures the further away you get from each pixel so that distant contributions (which are by definition more "averagable") are less expensive. But I don't really understand how the light transfer function works, what each texture is for, etc.
I would really appreciate a broad outline of the technique, because I'm finding it difficult to track anything at all in each episode!