change dither_c64() signature to take 'dimension' directly

2 files changed, 7 insertions, 6 deletions

diff --git a/src/effects/rotating_cube.wgsl b/src/effects/rotating_cube.wgsl
index abd584c..fcb4774 100644
--- a/src/effects/rotating_cube.wgsl
+++ b/src/effects/rotating_cube.wgsl
@@ -89,6 +89,7 @@ fn get_cube_normal(vid: u32) -> vec3f {
     let ambient = 0.3;
     let lighting = ambient + diffuse * 0.7;
 
-    let color = object.color.rgb * lighting;
-    return rgba_to_luma_chroma_phase(vec4f(color, 1.0), screen_uv.y, 264.);
+    var color = object.color * lighting;
+    color = dither_c64(color, screen_uv, uniforms.resolution / 2.);
+    return rgba_to_luma_chroma_phase(color, screen_uv.y, 264.);
 }
diff --git a/src/shaders/math/color_c64.wgsl b/src/shaders/math/color_c64.wgsl
index 60fde28..2a86919 100644
--- a/src/shaders/math/color_c64.wgsl
+++ b/src/shaders/math/color_c64.wgsl
@@ -44,10 +44,10 @@ 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_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;
+// dimension: virtual pixel grid dimensions (e.g. {54.*8., 33.*8.}).
+fn dither_c64(col: vec4f, uv: vec2f, dimension: vec2f) -> vec4f {
+  let ix = u32(floor(uv.x * dimension.x)) % 8;
+  let iy = u32(floor(uv.y * dimension.y)) % 8;
   let thresh = f32(BAYER_8X8[ix + 8 * iy]) / 64.;
 
   var color = min(col, vec4f(1.));