xref: /aosp_15_r20/external/skia/resources/sksl/intrinsics/Fwidth.sksl (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1*c8dee2aaSAndroid Build Coastguard Workeruniform half4 testInputs;  // equals (-1.25, 0, 0.75, 2.25)
2*c8dee2aaSAndroid Build Coastguard Workeruniform half4 colorGreen, colorRed;
3*c8dee2aaSAndroid Build Coastguard Worker
4*c8dee2aaSAndroid Build Coastguard Workerhalf4 main(float2 coords) {
5*c8dee2aaSAndroid Build Coastguard Worker    half4 expected = half4(0);  // derivative of a constant is zero
6*c8dee2aaSAndroid Build Coastguard Worker    return (dFdx(testInputs.x)      == expected.x     &&
7*c8dee2aaSAndroid Build Coastguard Worker            dFdx(testInputs.xy)     == expected.xy    &&
8*c8dee2aaSAndroid Build Coastguard Worker            dFdx(testInputs.xyz)    == expected.xyz   &&
9*c8dee2aaSAndroid Build Coastguard Worker            dFdx(testInputs.xyzw)   == expected.xyzw  &&
10*c8dee2aaSAndroid Build Coastguard Worker            sign(fwidth(coords.xx)) == half2(1, 1)        &&
11*c8dee2aaSAndroid Build Coastguard Worker            sign(fwidth(coords.x1)) == half2(1, 0)        &&
12*c8dee2aaSAndroid Build Coastguard Worker            sign(fwidth(coords.yy)) == half2(1, 1)        &&
13*c8dee2aaSAndroid Build Coastguard Worker            sign(fwidth(coords.0y)) == half2(0, 1)        &&
14*c8dee2aaSAndroid Build Coastguard Worker            sign(fwidth(coords.xy)) == half2(1, 1)) ? colorGreen : colorRed;
15*c8dee2aaSAndroid Build Coastguard Worker}
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