Addressed review comments

assets/voxygen/shaders/include/srgb.glsl

@@ -621,17 +621,23 @@ vec3 compute_attenuation_point(vec3 wpos, vec3 ray_dir, vec3 mu, float surface_a
 vec3 greedy_extract_col_light_glow(sampler2D t_col_light, vec2 f_uv_pos, out float f_light, out float f_glow) {
     uvec4 f_col_light = uvec4(texelFetch(t_col_light, ivec2(f_uv_pos), 0) * 255);
     vec3 f_col = vec3(
-        float(((f_col_light.r >> 4u) & 0xEu) | (((f_col_light.b >> 4u) & 0xFu) << 4u)),
+        float(((f_col_light.r << 1u) & 0xFu) | (((f_col_light.b >> 4u) & 0xFu) << 4u)),
         float(f_col_light.a),
-        float(((f_col_light.g >> 4u) & 0xEu) | (((f_col_light.b >> 0u) & 0xFu) << 4u))
+        float(((f_col_light.g << 1u) & 0xFu) | (((f_col_light.b >> 0u) & 0xFu) << 4u))
     ) / 255.0;
-    vec2 light_00 = vec2(uvec2(f_col_light.rg) & uvec2(0x1Fu));
-    vec2 light_10 = vec2(uvec2(texelFetch(t_col_light, ivec2(f_uv_pos) + ivec2(1, 0), 0).rg * 255.0) & uvec2(0x1Fu));
-    vec2 light_01 = vec2(uvec2(texelFetch(t_col_light, ivec2(f_uv_pos) + ivec2(0, 1), 0).rg * 255.0) & uvec2(0x1Fu));
-    vec2 light_11 = vec2(uvec2(texelFetch(t_col_light, ivec2(f_uv_pos) + ivec2(1, 1), 0).rg * 255.0) & uvec2(0x1Fu));
+
+    // TODO: Figure out how to use `texture` and modulation to avoid needing to do manual filtering
+    vec2 light_00 = vec2(uvec2(f_col_light.rg) >> 3u);
+    vec2 light_10 = vec2(uvec2(texelFetch(t_col_light, ivec2(f_uv_pos) + ivec2(1, 0), 0).rg * 255.0) >> 3u);
+    vec2 light_01 = vec2(uvec2(texelFetch(t_col_light, ivec2(f_uv_pos) + ivec2(0, 1), 0).rg * 255.0) >> 3u);
+    vec2 light_11 = vec2(uvec2(texelFetch(t_col_light, ivec2(f_uv_pos) + ivec2(1, 1), 0).rg * 255.0) >> 3u);
     vec2 light_0 = mix(light_00, light_01, fract(f_uv_pos.y));
     vec2 light_1 = mix(light_10, light_11, fract(f_uv_pos.y));
     vec2 light = mix(light_0, light_1, fract(f_uv_pos.x));
+    // TODO: Use `texture` instead
+    //vec2 light = texture(t_col_light, f_uv_pos).xy / 31;
+
+
     f_light = light.x / 31.0;
     f_glow = light.y / 31.0;
     return srgb_to_linear(f_col);

voxygen/src/render/pipelines/figure.rs

@@ -67,7 +67,7 @@ impl Locals {
 
         Self {
             model_mat: model_mat.into_col_arrays(),
-            highlight_col: [col.r, col.g, col.b, glow],
+            highlight_col: [col.r, col.g, col.b, 1.0],
             model_pos: pos.into_array(),
             atlas_offs: Vec4::from(atlas_offs).into_array(),
             model_light: [light, glow, 1.0, 1.0],

voxygen/src/render/pipelines/terrain.rs

@@ -115,15 +115,18 @@ impl Vertex {
         //
         // However, we now have a problem. In the shader code with use hardware filtering to
         // get at the `light` and `glow` attributes (but not colour, that remains constant
-        // across a block). How to we resolve this if we're twiddling bits? The answer is to
+        // across a block). How do we resolve this if we're twiddling bits? The answer is to
         // very carefully manipulate the bit pattern such that the fields we want to filter
-        // (`light` and `glow`) always sit as the lower bits of the fields. Then, we can do
+        // (`light` and `glow`) always sit as the higher bits of the fields. Then, we can do
         // some modulation magic to extract them from the filtering unharmed and use
         // unfiltered texture access (i.e: `texelFetch`) to access the colours, plus a little
         // bit-fiddling.
+        //
+        // TODO: This isn't currently working (no idea why). See `srgb.glsl` for current impl
+        // that intead does manual bit-twiddling and filtering.
         [
-            ((col.r & 0b1110) << 4) | light.min(31),
-            ((col.b & 0b1110) << 4) | glow.min(31),
+            (light.min(31) << 3) | ((col.r & 0b1110) >> 1),
+            (glow.min(31) << 3) | ((col.r & 0b1110) >> 1),
             (col.r & 0b11110000) | (col.b >> 4),
             col.g, // Green is lucky, it remains unscathed
         ]