From 7a05f4d33b611ba1e9b6c68e0d0bd67d6ea011ee Mon Sep 17 00:00:00 2001 From: skal Date: Tue, 10 Feb 2026 21:11:05 +0100 Subject: refactor: Optimize CNN grayscale computation Compute gray once per fragment using dot() instead of per-layer. Pass gray as f32 parameter to conv functions instead of vec4 original. Co-Authored-By: Claude Sonnet 4.5 --- doc/CNN_RGBD_GRAYSCALE_SUMMARY.md | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'doc/CNN_RGBD_GRAYSCALE_SUMMARY.md') diff --git a/doc/CNN_RGBD_GRAYSCALE_SUMMARY.md b/doc/CNN_RGBD_GRAYSCALE_SUMMARY.md index 4c13693..3439f2c 100644 --- a/doc/CNN_RGBD_GRAYSCALE_SUMMARY.md +++ b/doc/CNN_RGBD_GRAYSCALE_SUMMARY.md @@ -20,7 +20,7 @@ Implemented CNN architecture upgrade: RGBD input → grayscale output with 7-cha - **RGBD:** `(rgbd - 0.5) * 2` - **UV coords:** `(uv - 0.5) * 2` -- **Grayscale:** `(0.2126*R + 0.7152*G + 0.0722*B - 0.5) * 2` +- **Grayscale:** `dot(original.rgb, vec3(0.2126, 0.7152, 0.0722))` (computed once, passed as parameter) **Rationale:** Zero-centered inputs for tanh activation, better gradient flow. @@ -48,13 +48,14 @@ Implemented CNN architecture upgrade: RGBD input → grayscale output with 7-cha **Shaders (`/Users/skal/demo/workspaces/main/shaders/cnn/cnn_conv3x3.wgsl`):** 1. Added `cnn_conv3x3_7to4()`: - - 7-channel input: [RGBD, uv_x, uv_y, gray] + - 7-channel input: [RGBD, uv_x, uv_y, gray] (gray passed as parameter) - 4-channel output: RGBD - Weights: `array, 36>` 2. Added `cnn_conv3x3_7to1()`: - - 7-channel input: [RGBD, uv_x, uv_y, gray] + - 7-channel input: [RGBD, uv_x, uv_y, gray] (gray passed as parameter) - 1-channel output: grayscale - Weights: `array, 9>` +3. Optimized: gray computed once in caller using `dot()`, not per-function **Documentation (`/Users/skal/demo/doc/CNN_EFFECT.md`):** 1. Updated architecture section with RGBD→grayscale pipeline @@ -71,7 +72,8 @@ CNNLayerParams and bind groups remain unchanged. 2. Each layer: - Samples previous layer output (RGBD in [0,1]) - Normalizes RGBD to [-1,1] - - Computes UV coords and grayscale, normalizes to [-1,1] + - Computes gray once using `dot()` (fs_main level) + - Normalizes UV coords to [-1,1] (inside conv functions) - Concatenates 7-channel input - Applies convolution with layer-specific weights - Outputs RGBD (inner) or grayscale (final) in [-1,1] -- cgit v1.2.3