add uv to vertex format and remove it from instance

src/shaders/basic.wgsl

@@ -3,11 +3,10 @@ struct VertexShaderInput {
     @builtin(vertex_index) vertex_index: u32,
 
     @location(0) pos: vec3<f32>,
+    @location(1) uv:  vec2<f32>,
 
     // Per Instance
-    @location(1) pos_size: vec4<f32>,
-    @location(2) uv0uv1:   vec4<f32>,
-    @location(3) uv2uv3:   vec4<f32>,
+    @location(2) pos_size: vec4<f32>,
 };
 
 struct VertexShaderOutput {
@@ -26,14 +25,7 @@ struct FragmentShaderOutput {
     var output: VertexShaderOutput;
 
     output.pos = vec4<f32>(input.pos_size.xy + input.pos.xy, 0, 1) * view_projection_matrix;
-
-    switch (input.vertex_index) {
-        case 0: { output.uv = input.uv0uv1.xy; }
-        case 1: { output.uv = input.uv2uv3.zw; }
-        case 2: { output.uv = input.uv2uv3.xy; }
-        case 3: { output.uv = input.uv0uv1.zw; }
-        default: {}
-    }
+    output.uv  = input.uv;
 
     return output;
 }