struct VertexOut {
    @builtin(position) position : vec4f,
    @location(0) color : vec4f
};

@vertex
fn vertex_main(@location(0) position: vec4f,
               @location(1) color: vec4f) -> VertexOut {
    var output : VertexOut;
    output.position = position;
    output.color = color;
    return output;
}
