chore: cleanup examples

README.md

@@ -589,14 +589,12 @@ const geometry = new Geometry({
 })
 const computeMaterial = new Material({
   compute: /* glsl */ `#version 300 es
-    out vec2 position;
     out vec2 uv;
-
-    const vec2 vertex[3] = vec2[](vec2(-1), vec2(3, -1), vec2(-1, 3));
+    out vec2 position;
 
     void main() {
-      position = vertex[gl_VertexID];
-      uv = abs(position) - 1.0;
+      uv = vec2(gl_VertexID << 1 & 2, gl_VertexID & 2);
+      position = uv * 2.0 - 1.0;
     }
   `,
 })
@@ -623,12 +621,10 @@ const computeMaterial = new Material({
     @group(0) @binding(1)
     var<storage, read_write> uv: array<vec2<f32>>;
 
-    const vertex = array<vec2<f32>, 3>(vec2(-1), vec2(3, -1), vec2(-1, 3));
-
     @compute @workgroup_size(64)
     fn main(@builtin(local_invocation_index) i: u32) {
-      position[i] = vertex[i];
-      uv[i] = abs(vertex[i]) - 1.0;
+      uv[i] = vec2<f32>(vec2((i << 1) & 2, i & 2));
+      position[i] = uv[i] * 2 - 1;
     }
   `,
 })

examples/webgl-compute.ts

@@ -11,14 +11,12 @@ const geometry = new Geometry({
 
 const computeMaterial = new Material({
   compute: /* glsl */ `#version 300 es
-    out vec2 position;
     out vec2 uv;
-
-    const vec2 vertex[3] = vec2[](vec2(-1), vec2(3, -1), vec2(-1, 3));
+    out vec2 position;
 
     void main() {
-      position = vertex[gl_VertexID];
-      uv = abs(position) - 1.0;
+      uv = vec2(gl_VertexID << 1 & 2, gl_VertexID & 2);
+      position = uv * 2.0 - 1.0;
     }
   `,
 })

examples/webgl-fullscreen.ts

@@ -11,12 +11,10 @@ const material = new Material({
   },
   vertex: /* glsl */ `#version 300 es
     out vec2 vUv;
-
-    const vec2 triangle[3] = vec2[](vec2(-1), vec2(3, -1), vec2(-1, 3));
   
     void main() {
-      gl_Position = vec4(triangle[gl_VertexID], 0, 1);
-      vUv = abs(gl_Position.xy) - 1.0;
+      vUv = vec2(gl_VertexID << 1 & 2, gl_VertexID & 2);
+      gl_Position = vec4(vUv * 2.0 - 1.0, 0, 1);
     }
   `,
   fragment: /* glsl */ `#version 300 es

examples/webgpu-compute.ts

@@ -17,12 +17,10 @@ const computeMaterial = new Material({
     @group(0) @binding(1)
     var<storage, read_write> uv: array<vec2<f32>>;
 
-    const vertex = array<vec2<f32>, 3>(vec2(-1), vec2(3, -1), vec2(-1, 3));
-
     @compute @workgroup_size(64)
     fn main(@builtin(local_invocation_index) i: u32) {
-      position[i] = vertex[i];
-      uv[i] = abs(vertex[i]) - 1.0;
+      uv[i] = vec2<f32>(vec2((i << 1) & 2, i & 2));
+      position[i] = uv[i] * 2 - 1;
     }
   `,
 })

examples/webgpu-fullscreen.ts

@@ -21,13 +21,11 @@ const material = new Material({
       @location(1) uv: vec2<f32>,
     };
 
-    const triangle = array<vec2<f32>, 3>(vec2(-1), vec2(3, -1), vec2(-1, 3));
-
     @vertex
     fn main(@builtin(vertex_index) i: u32) -> VertexOut {
       var out: VertexOut;
-      out.position = vec4(triangle[i], 0, 1);
-      out.uv = abs(out.position.xy) - 1.0;
+      out.uv = vec2<f32>(vec2((i << 1) & 2, i & 2));
+      out.position = vec4(out.uv * 2 - 1, 0, 1);
       out.color = vec4(0.5 + 0.3 * cos(vec3(out.uv, 0.0) + uniforms.time), 0.0);
       return out;
     }