Please help me, I use
for (double u = NSF->Domain(0).Min(); u <= NSF->Domain(0).Max(); u+=uadd)
for (double v = NSF->Domain(1).Min(); v <= NSF->Domain(1).Max(); v+=vadd, )
ON_3dPoint point = srf.PointAt(u,v);
how to check if u/v is within the trimmed area?