rotating_cube: use VSOut, and store to yiq

3 files changed, 11 insertions, 6 deletions

diff --git a/src/effects/ntsc.wgsl b/src/effects/ntsc.wgsl
index e0182f3..3ee02bc 100644
--- a/src/effects/ntsc.wgsl
+++ b/src/effects/ntsc.wgsl
@@ -140,7 +140,7 @@ fn randomized_f32(p: vec2f, t: f32) -> f32 {
     var col = yiqa_to_rgba(signal);
     // Slight NTSC warm tint (boost red/green, attenuate blue)
     col *= vec4f(1.04, 1.01, .94, 1.);
-//    col = Dither(col, uv, XSIZE, YSIZE);
+//    col = dither_c64(col, uv, XSIZE, YSIZE);
 
     let border_col = get_border_c64(uv, uniforms.beat_time, YSIZE);
 
diff --git a/src/effects/rotating_cube.wgsl b/src/effects/rotating_cube.wgsl
index 0c75a13..abd584c 100644
--- a/src/effects/rotating_cube.wgsl
+++ b/src/effects/rotating_cube.wgsl
@@ -1,4 +1,8 @@
 // Rotating cube shader v2 (simplified, no masking)
+// output to YIQ color space
+
+#include "math/color"
+#include "math/color_c64"
 
 struct Uniforms {
     view_proj: mat4x4f,
@@ -76,8 +80,9 @@ fn get_cube_normal(vid: u32) -> vec3f {
     return VSOut(clip_pos, world_pos.xyz, world_normal);
 }
 
-@fragment fn fs_main(@location(0) world_pos: vec3f, @location(1) normal: vec3f) -> @location(0) vec4f {
-    let N = normalize(normal);
+@fragment fn fs_main(in: VSOut) -> @location(0) vec4f {
+    let screen_uv = in.pos.xy / uniforms.resolution;
+    let N = in.normal;  // not re-normalized: cube faces are flat, no drift
     let light_dir = normalize(vec3f(1.0, 1.0, 1.0));
     let diffuse = max(dot(N, light_dir), 0.0);
 
@@ -85,5 +90,5 @@ fn get_cube_normal(vid: u32) -> vec3f {
     let lighting = ambient + diffuse * 0.7;
 
     let color = object.color.rgb * lighting;
-    return vec4f(color, 1.0);
+    return rgba_to_luma_chroma_phase(vec4f(color, 1.0), screen_uv.y, 264.);
 }
diff --git a/src/shaders/math/color_c64.wgsl b/src/shaders/math/color_c64.wgsl
index e1b142e..60fde28 100644
--- a/src/shaders/math/color_c64.wgsl
+++ b/src/shaders/math/color_c64.wgsl
@@ -1,5 +1,5 @@
 // C64 palette, ordered-dither quantization, and border color animation.
-// Provides Dither() and get_border_c64() for NTSC and retro post-process effects.
+// Provides dither_c64() and get_border_c64() for NTSC and retro post-process effects.
 #include "math/noise"
 
 const NUM_COLORS : u32 = 16;
@@ -45,7 +45,7 @@ fn colorDistance(color: vec4f, c1: vec4f, c2: vec4f, frac: f32) -> f32 {
 
 // Quantize col to the nearest C64 color pair using 8x8 Bayer dithering.
 // xsize/ysize: virtual pixel grid dimensions (e.g. 54.*8., 33.*8.).
-fn Dither(col: vec4f, uv: vec2f, xsize: f32, ysize: f32) -> vec4f {
+fn dither_c64(col: vec4f, uv: vec2f, xsize: f32, ysize: f32) -> vec4f {
   let ix = u32(floor(uv.x * xsize / 2.)) % 8;
   let iy = u32(floor(uv.y * ysize / 2.)) % 8;
   let thresh = f32(BAYER_8X8[ix + 8 * iy]) / 64.;