Merge pull request #1885 from bungoboingo/gradient-packing-optimization

Small gradient optimization

2 files changed, 102 insertions, 110 deletions

diff --git a/wgpu/src/shader/quad.wgsl b/wgpu/src/shader/quad.wgsl
index 3232bdbe..fb402158 100644
--- a/wgpu/src/shader/quad.wgsl
+++ b/wgpu/src/shader/quad.wgsl
@@ -38,6 +38,13 @@ fn select_border_radius(radi: vec4<f32>, position: vec2<f32>, center: vec2<f32>)
     return rx;
 }
 
+fn unpack_u32(color: vec2<u32>) -> vec4<f32> {
+    let rg: vec2<f32> = unpack2x16float(color.x);
+    let ba: vec2<f32> = unpack2x16float(color.y);
+
+    return vec4<f32>(rg.y, rg.x, ba.y, ba.x);
+}
+
 struct SolidVertexInput {
     @location(0) v_pos: vec2<f32>,
     @location(1) color: vec4<f32>,
@@ -140,40 +147,30 @@ fn solid_fs_main(
 
 struct GradientVertexInput {
     @location(0) v_pos: vec2<f32>,
-    @location(1) color_1: vec4<f32>,
-    @location(2) color_2: vec4<f32>,
-    @location(3) color_3: vec4<f32>,
-    @location(4) color_4: vec4<f32>,
-    @location(5) color_5: vec4<f32>,
-    @location(6) color_6: vec4<f32>,
-    @location(7) color_7: vec4<f32>,
-    @location(8) color_8: vec4<f32>,
-    @location(9) offsets_1: vec4<f32>,
-    @location(10) offsets_2: vec4<f32>,
-    @location(11) direction: vec4<f32>,
-    @location(12) position_and_scale: vec4<f32>,
-    @location(13) border_color: vec4<f32>,
-    @location(14) border_radius: vec4<f32>,
-    @location(15) border_width: f32
+    @location(1) colors_1: vec4<u32>,
+    @location(2) colors_2: vec4<u32>,
+    @location(3) colors_3: vec4<u32>,
+    @location(4) colors_4: vec4<u32>,
+    @location(5) offsets: vec4<u32>,
+    @location(6) direction: vec4<f32>,
+    @location(7) position_and_scale: vec4<f32>,
+    @location(8) border_color: vec4<f32>,
+    @location(9) border_radius: vec4<f32>,
+    @location(10) border_width: f32,
 }
 
 struct GradientVertexOutput {
     @builtin(position) position: vec4<f32>,
-    @location(1) color_1: vec4<f32>,
-    @location(2) color_2: vec4<f32>,
-    @location(3) color_3: vec4<f32>,
-    @location(4) color_4: vec4<f32>,
-    @location(5) color_5: vec4<f32>,
-    @location(6) color_6: vec4<f32>,
-    @location(7) color_7: vec4<f32>,
-    @location(8) color_8: vec4<f32>,
-    @location(9) offsets_1: vec4<f32>,
-    @location(10) offsets_2: vec4<f32>,
-    @location(11) direction: vec4<f32>,
-    @location(12) position_and_scale: vec4<f32>,
-    @location(13) border_color: vec4<f32>,
-    @location(14) border_radius: vec4<f32>,
-    @location(15) border_width: f32
+    @location(1) colors_1: vec4<u32>,
+    @location(2) colors_2: vec4<u32>,
+    @location(3) colors_3: vec4<u32>,
+    @location(4) colors_4: vec4<u32>,
+    @location(5) offsets: vec4<u32>,
+    @location(6) direction: vec4<f32>,
+    @location(7) position_and_scale: vec4<f32>,
+    @location(8) border_color: vec4<f32>,
+    @location(9) border_radius: vec4<f32>,
+    @location(10) border_width: f32,
 }
 
 @vertex
@@ -199,16 +196,11 @@ fn gradient_vs_main(input: GradientVertexInput) -> GradientVertexOutput {
     );
 
     out.position = globals.transform * transform * vec4<f32>(input.v_pos, 0.0, 1.0);
-    out.color_1 = input.color_1;
-    out.color_2 = input.color_2;
-    out.color_3 = input.color_3;
-    out.color_4 = input.color_4;
-    out.color_5 = input.color_5;
-    out.color_6 = input.color_6;
-    out.color_7 = input.color_7;
-    out.color_8 = input.color_8;
-    out.offsets_1 = input.offsets_1;
-    out.offsets_2 = input.offsets_2;
+    out.colors_1 = input.colors_1;
+    out.colors_2 = input.colors_2;
+    out.colors_3 = input.colors_3;
+    out.colors_4 = input.colors_4;
+    out.offsets = input.offsets;
     out.direction = input.direction * globals.scale;
     out.position_and_scale = vec4<f32>(pos, scale);
     out.border_color = input.border_color;
@@ -274,25 +266,28 @@ fn gradient(
 @fragment
 fn gradient_fs_main(input: GradientVertexOutput) -> @location(0) vec4<f32> {
     let colors = array<vec4<f32>, 8>(
-        input.color_1,
-        input.color_2,
-        input.color_3,
-        input.color_4,
-        input.color_5,
-        input.color_6,
-        input.color_7,
-        input.color_8,
+        unpack_u32(input.colors_1.xy),
+        unpack_u32(input.colors_1.zw),
+        unpack_u32(input.colors_2.xy),
+        unpack_u32(input.colors_2.zw),
+        unpack_u32(input.colors_3.xy),
+        unpack_u32(input.colors_3.zw),
+        unpack_u32(input.colors_4.xy),
+        unpack_u32(input.colors_4.zw),
     );
 
+    let offsets_1: vec4<f32> = unpack_u32(input.offsets.xy);
+    let offsets_2: vec4<f32> = unpack_u32(input.offsets.zw);
+
     var offsets = array<f32, 8>(
-        input.offsets_1.x,
-        input.offsets_1.y,
-        input.offsets_1.z,
-        input.offsets_1.w,
-        input.offsets_2.x,
-        input.offsets_2.y,
-        input.offsets_2.z,
-        input.offsets_2.w,
+        offsets_1.x,
+        offsets_1.y,
+        offsets_1.z,
+        offsets_1.w,
+        offsets_2.x,
+        offsets_2.y,
+        offsets_2.z,
+        offsets_2.w,
     );
 
     //TODO could just pass this in to the shader but is probably more performant to just check it here
diff --git a/wgpu/src/shader/triangle.wgsl b/wgpu/src/shader/triangle.wgsl
index 625fa46e..9f512d14 100644
--- a/wgpu/src/shader/triangle.wgsl
+++ b/wgpu/src/shader/triangle.wgsl
@@ -4,6 +4,13 @@ struct Globals {
 
 @group(0) @binding(0) var<uniform> globals: Globals;
 
+fn unpack_u32(color: vec2<u32>) -> vec4<f32> {
+    let rg: vec2<f32> = unpack2x16float(color.x);
+    let ba: vec2<f32> = unpack2x16float(color.y);
+
+    return vec4<f32>(rg.y, rg.x, ba.y, ba.x);
+}
+
 struct SolidVertexInput {
     @location(0) position: vec2<f32>,
     @location(1) color: vec4<f32>,
@@ -29,52 +36,39 @@ fn solid_fs_main(input: SolidVertexOutput) -> @location(0) vec4<f32> {
     return input.color;
 }
 
+struct GradientVertexInput {
+    @location(0) v_pos: vec2<f32>,
+    @location(1) colors_1: vec4<u32>,
+    @location(2) colors_2: vec4<u32>,
+    @location(3) colors_3: vec4<u32>,
+    @location(4) colors_4: vec4<u32>,
+    @location(5) offsets: vec4<u32>,
+    @location(6) direction: vec4<f32>,
+}
+
 struct GradientVertexOutput {
     @builtin(position) position: vec4<f32>,
     @location(0) raw_position: vec2<f32>,
-    @location(1) color_1: vec4<f32>,
-    @location(2) color_2: vec4<f32>,
-    @location(3) color_3: vec4<f32>,
-    @location(4) color_4: vec4<f32>,
-    @location(5) color_5: vec4<f32>,
-    @location(6) color_6: vec4<f32>,
-    @location(7) color_7: vec4<f32>,
-    @location(8) color_8: vec4<f32>,
-    @location(9) offsets_1: vec4<f32>,
-    @location(10) offsets_2: vec4<f32>,
-    @location(11) direction: vec4<f32>,
+    @location(1) colors_1: vec4<u32>,
+    @location(2) colors_2: vec4<u32>,
+    @location(3) colors_3: vec4<u32>,
+    @location(4) colors_4: vec4<u32>,
+    @location(5) offsets: vec4<u32>,
+    @location(6) direction: vec4<f32>,
 }
 
 @vertex
-fn gradient_vs_main(
-    @location(0) input: vec2<f32>,
-    @location(1) color_1: vec4<f32>,
-    @location(2) color_2: vec4<f32>,
-    @location(3) color_3: vec4<f32>,
-    @location(4) color_4: vec4<f32>,
-    @location(5) color_5: vec4<f32>,
-    @location(6) color_6: vec4<f32>,
-    @location(7) color_7: vec4<f32>,
-    @location(8) color_8: vec4<f32>,
-    @location(9) offsets_1: vec4<f32>,
-    @location(10) offsets_2: vec4<f32>,
-    @location(11) direction: vec4<f32>,
-) -> GradientVertexOutput {
+fn gradient_vs_main(input: GradientVertexInput) -> GradientVertexOutput {
     var output: GradientVertexOutput;
 
-    output.position = globals.transform * vec4<f32>(input.xy, 0.0, 1.0);
-    output.raw_position = input;
-    output.color_1 = color_1;
-    output.color_2 = color_2;
-    output.color_3 = color_3;
-    output.color_4 = color_4;
-    output.color_5 = color_5;
-    output.color_6 = color_6;
-    output.color_7 = color_7;
-    output.color_8 = color_8;
-    output.offsets_1 = offsets_1;
-    output.offsets_2 = offsets_2;
-    output.direction = direction;
+    output.position = globals.transform * vec4<f32>(input.v_pos, 0.0, 1.0);
+    output.raw_position = input.v_pos;
+    output.colors_1 = input.colors_1;
+    output.colors_2 = input.colors_2;
+    output.colors_3 = input.colors_3;
+    output.colors_4 = input.colors_4;
+    output.offsets = input.offsets;
+    output.direction = input.direction;
 
     return output;
 }
@@ -135,25 +129,28 @@ fn gradient(
 @fragment
 fn gradient_fs_main(input: GradientVertexOutput) -> @location(0) vec4<f32> {
     let colors = array<vec4<f32>, 8>(
-        input.color_1,
-        input.color_2,
-        input.color_3,
-        input.color_4,
-        input.color_5,
-        input.color_6,
-        input.color_7,
-        input.color_8,
+        unpack_u32(input.colors_1.xy),
+        unpack_u32(input.colors_1.zw),
+        unpack_u32(input.colors_2.xy),
+        unpack_u32(input.colors_2.zw),
+        unpack_u32(input.colors_3.xy),
+        unpack_u32(input.colors_3.zw),
+        unpack_u32(input.colors_4.xy),
+        unpack_u32(input.colors_4.zw),
     );
 
+    let offsets_1: vec4<f32> = unpack_u32(input.offsets.xy);
+    let offsets_2: vec4<f32> = unpack_u32(input.offsets.zw);
+
     var offsets = array<f32, 8>(
-        input.offsets_1.x,
-        input.offsets_1.y,
-        input.offsets_1.z,
-        input.offsets_1.w,
-        input.offsets_2.x,
-        input.offsets_2.y,
-        input.offsets_2.z,
-        input.offsets_2.w,
+        offsets_1.x,
+        offsets_1.y,
+        offsets_1.z,
+        offsets_1.w,
+        offsets_2.x,
+        offsets_2.y,
+        offsets_2.z,
+        offsets_2.w,
     );
 
     var last_index = 7;