Part of DXPlay.fs showing the bit you code to make shapes :)

Shader.fs

let computeShader =
        let code = @"
            RWTexture2D<float4> Output;

            [numthreads(32, 32, 1)]
            void main( uint3 threadID : SV_DispatchThreadID )
            {
                for (int i = 1.0f; i <= 1280.0f; i+=320.0f){
                    Output[threadID.xy] = float4(threadID.xy / i, 0, 1);
                }
            }
        "