struct VertexOutput {
    @builtin(position) clip_position: vec4<f32>,
    @location(0) color: vec4<f32>
};

@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<f32>(x, y, 0.0, 1.0);
    out.color = vec4<f32>(0.3,x,y,1.0);
    return out;
}

@fragment
fn fs_main(@location(0) col: vec4<f32>) -> @location(0) vec4<f32> {
    return col;
}