#include #include using namespace metal; struct Inputs { float a; }; struct Outputs { float4 sk_FragColor [[color(0)]]; }; fragment Outputs fragmentMain(Inputs _in [[stage_in]], bool _frontFacing [[front_facing]], float4 _fragCoord [[position]]) { Outputs _out; (void)_out; _out.sk_FragColor.x = float(isnan(_in.a) ? 1 : 0); return _out; }