Addresses interpolation artifacts during cascade merging. The four bilinearly sampled upper-cascade probes have spatial offsets, causing discontinuities at probe boundaries. The fix casts 4× rays — one reprojected to each upper-cascade bilinear probe — before merging, making merged rays continuous.
Tradeoff: 4× ray cost. For a cheaper alternative, see the nearest-fix.
| Without fix | With bilinear fix |
|---|---|
Images from Yaazarai’s GMShaders repo.
- Formal treatment: Osborne & Sannikov 2024, Appendix A
- Shadertoy: Radiance Cascades V2 by MytinoDev
- Implementation: Yaazarai’s repo (bilinear-fix branch)
- Interactive toggle: radiance-cascades.com
Related: nearest-fix · parallax-fix (different artifact)