I took below effect code from a tutorial that I was recommended, gmjosack on GitHub. First test worked, after installing some DirectX libraries and compiling for a different version of DirectX. now what goes wrong, do I need different syntax for this version? Using MonoGame 3.6 and VS2017. Any help appreciated, as well as links to good tutorials on shaders in 2D. Thanks.
float4 PixelShaderFunction(float2 coords: TEXCOORD0) : COLOR0
float4 color = tex2D(s0, coords);
PixelShader = compile ps_4_0_level_9_1 PixelShaderFunction();