out vec4 sk_FragColor; uniform vec4 colorGreen; uniform vec4 colorRed; uniform mat3 testMatrix3x3; uniform mat4 testMatrix4x4; bool test3x3_b() { mat3 matrix = testMatrix3x3; vec3 expected = vec3(1.0, 2.0, 3.0); for (int index = 0;index < 3; ++index) { if (matrix[index] != expected) { return false; } expected += 3.0; } return true; } bool test4x4_b() { mat4 matrix = testMatrix4x4; vec4 expected = vec4(1.0, 2.0, 3.0, 4.0); for (int index = 0;index < 4; ++index) { if (matrix[index] != expected) { return false; } expected += 4.0; } return true; } vec4 main() { return test3x3_b() && test4x4_b() ? colorGreen : colorRed; }