uniform half4 testInputs;  // -1.25, 0, 0.75, 2.25
uniform half4 colorGreen, colorRed;

half4 main(float2 coords) {
    const float4 expectedA = half4(-1.0, 0.0, 1.0, 2.0);

    const float4 constVal = half4(-6.75, -0.475, 3.5, 2.5);
    const float4 expectedB = half4(-7.0, -0.0, 4.0, 2.0);
    return (roundEven(testInputs.x)    == expectedA.x     &&
            roundEven(testInputs.xy)   == expectedA.xy    &&
            roundEven(testInputs.xyz)  == expectedA.xyz   &&
            roundEven(testInputs.xyzw) == expectedA.xyzw  &&
            roundEven(constVal.x)      == expectedB.x     &&
            roundEven(constVal.xy)     == expectedB.xy    &&
            roundEven(constVal.xyz)    == expectedB.xyz   &&
            roundEven(constVal.xyzw)   == expectedB.xyzw) ? colorGreen : colorRed;
}