# Chapter 19. Deferred Shading in Tabula Rasa — Rusty Koonce

- Source: https://developer.nvidia.com/gpugems/gpugems3/part-iii-rendering/chapter-19-deferred-shading-tabula-rasa
- Volume: GPU Gems 3
- Note: add-only excerpt for wiki ingest; images omitted; prose and key listings kept.

## Summary of full chapter read

Production deferred engine for MMO Tabula Rasa; companion to Shishkovtsov STALKER chapter. Forward kept for translucency + low-end fallback.

### Features enabled by deferred
Bidirectional directional lights (front+back color); globe maps (cube/2D colorize light); box lights (localized directional with falloff); exclusive dynamic shadow maps with pools; static/dynamic caster flags.

### Depth/normal buffer uses
Water depth-aware shoreline/refraction; resolution-independent edge detect (relative depth gradients + normal angle) for fake AA blend.

### Caveats & opts
SM3: 4 MRTs, hide layout behind accessors. View-space normals in 2 channels. Bandwidth dominates — resolution is #1 cost knob. Separate diffuse/specular accumulation RTs. Tight light volumes; stencil sky; dynamic branch on distance. Alpha: force hair/flora to alpha-test into deferred; scale flora for fake fade. Quantize light matrices for stable shadows. Global SM used large ortho 2K (PSM/TSM quality varied with sun angle).