docs: Record Task 21.2 completion and update session priorities

1 files changed, 2 insertions, 2 deletions

diff --git a/TODO.md b/TODO.md
index a6f3d37..7e59cee 100644
--- a/TODO.md
+++ b/TODO.md
@@ -18,8 +18,7 @@ This file tracks prioritized tasks with detailed attack plans.
 
 ## Priority 3: Shader Optimization (Task #21)
 **Goal:** Improve GPU performance and reduce shader source bloat.
-- [ ] **Attack Plan - Normal Factorization:** Create a standard WGSL helper for normal calculation to avoid duplicate code in every effect.
-- [ ] **Attack Plan - Ray Bounds:** Derive `t_min` and `t_max` for ray-marching from the proxy hull entry/exit points to minimize iterations.
+- [ ] **Attack Plan - WGSL Library (21.1):** Create a standard set of WGSL includes/helpers for normals, bump mapping, and lighting.
 - [ ] **Attack Plan - SDF Macros:** Use `#define` macros in WGSL to simplify sampling and bump mapping logic.
 
 ## Future Goals
@@ -28,6 +27,7 @@ This file tracks prioritized tasks with detailed attack plans.
 - [ ] **Task #22: Windows Native Platform**: Replace GLFW with direct Win32 API calls for the final 64k push.
 
 ## Recently Completed
+- [x] **Tight Ray Bounds (Task 21.2)**: Derived t_min and t_max from proxy hull hits via local-space ray-box intersection.
 - [x] **High-DPI Fix**: Resolved viewport "squishing" via dynamic resolution uniforms and explicit viewports.
 - [x] **Unified 3D Shadows**: Implemented robust SDF shadows across all objects using `inv_model` transforms.
 - [x] **Tight Proxy Hulls**: Optimized Torus proxy geometry and debug wireframes.