RDW

I just looked into this again, and I noticed two things: 1. This issue was originally supposed to be about the bounding box, not the scene graph/quad tree. Whoops? 2....

As far as I can tell, all the modern GND files use version 1.7. The files from Arcturus/the iRO alpha use a different version, but since they don't have any...

Update: It seems I didn't have the latest files from kRO. After updating, I've just encountered this error:  I'm willing to bet the original comment was referring to 1.8...

It looks like they changed the RSM(2) model actor definition; there's a lot more data in there now. Luckily I was able to find the known properties present in previous...

Presumed structure so far (still need to check out some other 2.6 maps):  Update: I forgot about the node name and block type. It seems like the only change...

Looks like the maps available [here](https://storage.googleapis.com/google-code-archive-downloads/v2/code.google.com/aerie-pinkpanther/alphamaps.rar) are already converted to GND version 1.7. While that's not sufficient by itself, it could help with verifying the results of my own research...

As expected, the alpha maps don't have any lightmap data (only shadows). This is easily seen after loading the converted maps, as the entirety of the lightmap cache features 100%...

Also, some maps aren't working at all: ``prt_dugn01.rsw`` crashes the decoder; apparently the last scene object (expected to be a light source) references a ``.spr`` file? That's really weird.

The SPR object being present makes me think of Arcturus, so that might be another venue of research. Perhaps they just lifted the format from there, possibly with minor modifications?...

Just randomly found this while checking some lightmap-related stuff. I'd guess that the 68 "???" bytes outlined in the OP are 64 alpha values (one byte each, 8x8 lightmap slices...