From 288f62bfb691a91e01b9ddbce9dbdc560ee9036a Mon Sep 17 00:00:00 2001
From: Héctor Ramón Jiménez <hector@hecrj.dev>
Date: Sun, 7 Apr 2024 18:45:30 +0200
Subject: Share `msaa::Blit` texture between multiple windows

---
 wgpu/src/shader/blit.wgsl | 20 +++++++-------------
 1 file changed, 7 insertions(+), 13 deletions(-)

(limited to 'wgpu/src/shader/blit.wgsl')

diff --git a/wgpu/src/shader/blit.wgsl b/wgpu/src/shader/blit.wgsl
index c2ea223f..d7633808 100644
--- a/wgpu/src/shader/blit.wgsl
+++ b/wgpu/src/shader/blit.wgsl
@@ -1,22 +1,14 @@
-var<private> positions: array<vec2<f32>, 6> = array<vec2<f32>, 6>(
-    vec2<f32>(-1.0, 1.0),
-    vec2<f32>(-1.0, -1.0),
-    vec2<f32>(1.0, -1.0),
-    vec2<f32>(-1.0, 1.0),
-    vec2<f32>(1.0, 1.0),
-    vec2<f32>(1.0, -1.0)
-);
-
 var<private> uvs: array<vec2<f32>, 6> = array<vec2<f32>, 6>(
     vec2<f32>(0.0, 0.0),
-    vec2<f32>(0.0, 1.0),
+    vec2<f32>(1.0, 0.0),
     vec2<f32>(1.0, 1.0),
     vec2<f32>(0.0, 0.0),
-    vec2<f32>(1.0, 0.0),
+    vec2<f32>(0.0, 1.0),
     vec2<f32>(1.0, 1.0)
 );
 
 @group(0) @binding(0) var u_sampler: sampler;
+@group(0) @binding(1) var<uniform> u_ratio: vec2<f32>;
 @group(1) @binding(0) var u_texture: texture_2d<f32>;
 
 struct VertexInput {
@@ -30,9 +22,11 @@ struct VertexOutput {
 
 @vertex
 fn vs_main(input: VertexInput) -> VertexOutput {
+    let uv = uvs[input.vertex_index];
+
     var out: VertexOutput;
-    out.uv = uvs[input.vertex_index];
-    out.position = vec4<f32>(positions[input.vertex_index], 0.0, 1.0);
+    out.uv = uv * u_ratio;
+    out.position = vec4<f32>(uv * vec2(2.0, -2.0) + vec2(-1.0, 1.0), 0.0, 1.0);
 
     return out;
 }
-- 
cgit