CNN v2: Add TODO for flexible feature layout in binary format v3

Document future enhancement for arbitrary feature vector layouts.

Proposed feature descriptor in binary format v3:
- Specify feature types, sources, and ordering
- Enable runtime experimentation without shader recompilation
- Examples: [R,G,B,dx,dy,uv_x,bias] or [mip1.r,mip2.g,laplacian,uv_x,sin20_x,bias]

Added TODOs in:
- CNN_V2_BINARY_FORMAT.md: Detailed proposal with struct layout
- CNN_V2.md: Future extensions section
- train_cnn_v2.py: compute_static_features() docstring
- cnn_v2_static.wgsl: Shader header comment
- cnn_v2_effect.cc: Version check comment

Current limitation: Hardcoded [p0,p1,p2,p3,uv_x,uv_y,sin10_x,bias] layout.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/workspaces/main/shaders/cnn_v2/cnn_v2_static.wgsl b/workspaces/main/shaders/cnn_v2/cnn_v2_static.wgsl
index f71fad2..29acddd 100644
--- a/workspaces/main/shaders/cnn_v2/cnn_v2_static.wgsl
+++ b/workspaces/main/shaders/cnn_v2/cnn_v2_static.wgsl
@@ -2,6 +2,10 @@
 // Generates 8D parametric features: [p0, p1, p2, p3, uv.x, uv.y, sin10_x, bias]
 // p0-p3: Parametric features from specified mip level (0=mip0, 1=mip1, 2=mip2, 3=mip3)
 // Note: Input image RGBD (mip0) fed separately to Layer 0
+//
+// TODO: Binary format should support arbitrary layout and ordering for feature vector (7D).
+//       Current layout is hardcoded. Future versions should allow runtime-specified
+//       feature combinations (e.g., [R, G, B, dx, dy, uv_x, bias] or custom encodings).
 
 struct StaticFeatureParams {
   mip_level: u32,