car brightness broken after collision export

[mrwonko]

Taking a vanilla cdb file and re-exporting it breaks car brightness for some reason.

Possible culprits:

• there's a hidden invariant that requires surfaces (or some other data) to be ordered a specific way, which I violate
• there's a lookup table in another file that needs to be kept in sync with the surfaces (and their ordering)
• the scale factors for the coordinate system must be kept in sync with something (shadowmap extents? some .bed file?)

[mrwonko]

f270524 added shadowmap import. I tried manually aligning it, which was nontrivial. So I assume there must be a mapping defined somewhere, i.e. where does the shadowmap start and end? It doesn't look like the collision file contains this info, so I find it unlikely that the issue is related to the shadowmap, but I'll need to perform more experiments to narrow it down.