docs: Mark Task #53 (Particles Shader Polish) as complete

1 files changed, 6 insertions, 1 deletions

diff --git a/TODO.md b/TODO.md
index dfa2b20..3c382d6 100644
--- a/TODO.md
+++ b/TODO.md
@@ -287,7 +287,12 @@ This file tracks prioritized tasks with detailed attack plans.
 ## Future Goals & Ideas (Untriaged)
 
 - [ ] **Task #52: Procedural SDF Font**: Minimal bezier/spline set for [A-Z, 0-9] and SDF rendering.
-- [ ] **Task #53: Particles Shader Polish**: Improve visual quality of particles.
+- [x] **Task #53: Particles Shader Polish**: Improve visual quality of particles. (Completed February 6, 2026)
+  - Implemented transparent circular particles with smooth distance-based falloff
+  - Added UV coordinates and lifetime-based alpha fading (particle.pos.w: 1.0 → 0.0)
+  - Enabled alpha blending for particle shaders (auto-detected via shader name)
+  - Increased particle usage: Added 5 ParticleSprayEffect instances throughout demo (6b, 12b, 17b, 24b, 56b)
+  - Result: Particles now render as fading transparent circles instead of opaque squares
 - [ ] **Task #55: SDF Random Planes Intersection**: Implement `sdPolyhedron` (crystal/gem shapes) via plane intersection.
 - [ ] **Task #54: Tracy Integration**: Integrate Tracy debugger for performance profiling.
 - [ ] **Task #58: Advanced Shader Factorization**: Further factorize WGSL code into smaller, reusable snippets.