Great, thanks for the info! I suspected it was done by hand.

I'm trying to build a similar model but I haven't found many leads on generating the spiral arms correctly outside of downloading a bunch of Gaia data and mass processing it somehow. Any suggestions? :)

File sizes take a slight hit. This model is 12.7mb as a zstd-compressed array, 16.2mb as a SVO DAG in the previous implementation and 23.4mb as a 64-tree. Leaf data deduplicates easily and is about 2mb here. The rest is for the node storage which is harder to compress.

And that's good though for materials and small scenes. I could use uint textures for larger scenes.

I'd have to use a full screen triangle instead of the compute shader, but I'm already doing one of those because your can't write directly to the framebuffer in a compute shader. The lack of (unlimited size) storage buffers would be more of an issue, but webgl2 gives you 64k for uniform buffers

Oh, vec3<bool> & vec3<bool> works. Maybe it's a naga issue then?

In my case, I mostly want read-write storage buffers so I can have an accumulation buffer for raytracing. At the moment I'd have to have two buffers and do a texture sample from one and a write into the other.