[photon137]

Voxels would be too heavy. I have worked with volume rendering before and it's way too expensive to do it at this scale (although their scene with the light passing through the volumetric smoke column kind-of defied this).

Some real-time version of PRT? "RTRT"?

[dualogy]

Turns out it IS voxels! https://twitter.com/Icare3D/status/211404654062481408

(Of course the (fairly lo-res compared to your screen) voxelized geometry representation is not rendered directly to screen ala Atomontage or Gigavoxels -- the the GI is based on RT scene voxelization and approximate cone-tracing.)

Well that's awesome because at least there's (A) a paper for this (grokking it is another matter) and (B) seems like it runs really smoothly on next-gen GPUs!

[photon137]

lo-res being the key :) I can see how the voxel representation would be computed and made resident in GPU memory. What's amazing to me, that such a highly branched computation algorithm is now possible in real-time on a GPU! (we had branching available since SM 3.0 - but was "not recommended")