struct VertexOutput { [[builtin(position)]] clip_position: vec4; }; [[stage(vertex)]] fn vs_main( [[builtin(vertex_index)]] in_vertex_index: u32, ) -> VertexOutput { var out: VertexOutput; let x = f32(1 - i32(in_vertex_index)) * 0.5; let y = f32(i32(in_vertex_index & 1u) * 2 - 1) * 0.5; out.clip_position = vec4(x, y, 0.0, 1.0); return out; } [[stage(fragment)]] fn fs_main(in: VertexOutput) -> [[location(0)]] vec4 { return vec4(0.3, 0.2, 0.1, 1.0); }