38 static int value(
const PointType& a,
const PointType& b,
const PointType& c)
44 B2Vector3D c2b(b.X() - c.X(), b.Y() - c.Y(), 0.0);
45 B2Vector3D b2a(a.X() - b.X(), a.Y() - b.Y(), 0.0);
47 double angle = atan2(b2a[0], b2a[1]) - atan2(c2b[0], c2b[1]);
49 double sigmaan = (sigma_a.
Mag() + sigma_b.
Mag() + sigma_c.
Mag()) / (3.*(c2b.
Mag() + b2a.
Mag()));
50 if (angle < (-sigmaan)) {
return -1; }
51 else if (angle > sigmaan) {
return 1; }