Since merging averages the four nearest upper-cascade probes’ rays, you can average them before storing — casting 4 rays, storing one averaged result. 75% memory reduction, texture lookups during merging drop from 16 to 4.
Combined with direction-first-probes, enables an RC implementation in under 100 lines of shader code.
- Described in: GM Shaders Part 2
- Origin: Graphics Programming Discord
Related: direction-first-probes