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; } @fragment fn fragment_main(fragData: VertexOut) -> @location(0) vec4f { return fragData.color; }