BC6 Texture Compression

[RobertBeckebans]

This is for the baked light data. The RBDoom 1.3 release shipped with 6 GB of .exr files but unfortunately I overlooked the size of the generated .bimage files that followed after playing the maps. So the data increased up to 15 GB which is really a lot.

R11G11B10 has 4 bytes per pixel but BC6 has only 1 byte per pixel.

The goal is to get a fast BC6 encoder running and to write a command that caches all env/maps/* .exr files to generated .bimage files and only ship those with the RBDoom 1.6 release.