I am in the process of writing a Lightmapper and I discovered this video about Quake's lightmapping process: https://www.youtube.com/watch?v=bxientPsqRg
The video discusses that the polygon is somehow "projected" onto the lightmap texture with an affine transform in such a way that the lightmap pixels ("luxels") are uniformly distributed (in the case of quake, 1 "luxel" per 16 texels).
If I have a regular 3D mesh, how do I project a polygon into such a texture? The video just says "computed with a few vectors" but does not explain what is actually done.
I think - what I want - is something like this:
Each polygon gets its own little rectangular texture.
Related question:
As I understood the video, the each polygon gets its own texture.
Does that mean the luxels in the red/green portions are calculated multiple times (once for the green polygon, once for the red polygon and once for each other polygon that covers this area)?
