1 2uniform vec2 u_skRTFlip; 3out vec4 sk_FragColor; 4void main() { 5 bool sk_Clockwise = gl_FrontFacing; 6 if (u_skRTFlip.y < 0.0) { 7 sk_Clockwise = !sk_Clockwise; 8 } 9 sk_FragColor = vec4(float(sk_Clockwise ? 1 : -1)); 10} 11