third_party/skia_next/third_party/skia/tests/sksl/workarounds/NegatedAtan.glsl

#version 400
out vec4 sk_FragColor;
uniform float unknownInput;
void main() {
    vec2 x = vec2(unknownInput);
    sk_FragColor.x = atan(x.x, -1.0 * x.y);
}