PackedVaryings vert(Attributes input) { Varyings output = (Varyings)0; output = BuildVaryings(input); PackedVaryings packedOutput = PackVaryings(output); return packedOutput; } half4 frag(PackedVaryings packedInput) : SV_TARGET { Varyings unpacked = UnpackVaryings(packedInput); SurfaceDescriptionInputs surfaceDescriptionInputs = BuildSurfaceDescriptionInputs(unpacked); SurfaceDescription surfaceDescription = SurfaceDescriptionFunction(surfaceDescriptionInputs); return surfaceDescription.Out; }