let pos : array<vec2<f32>, 3> = array<vec2<f32>, 3>(vec2<f32>(0.0, 0.5), vec2<f32>(-0.5, -0.5), vec2<f32>(0.5, -0.5));

@vertex
fn vtx_main(@builtin(vertex_index) VertexIndex : u32) -> @builtin(position) vec4<f32> {
  return vec4<f32>(pos[VertexIndex], 0.0, 1.0);
}

@fragment
fn frag_main() -> @location(0) vec4<f32> {
  return vec4<f32>(1.0, 0.0, 0.0, 1.0);
}