isEar function

dynamic isEar(
  1. dynamic ear
)

Implementation

isEar(ear) {
  var a = ear.prev, b = ear, c = ear.next;

  if (area(a, b, c) >= 0) return false; // reflex, can't be an ear

  // now make sure we don't have other points inside the potential ear
  var p = ear.next.next;

  while (p != ear.prev) {
    if (pointInTriangle(a.x, a.y, b.x, b.y, c.x, c.y, p.x, p.y) && area(p.prev, p, p.next) >= 0) return false;
    p = p.next;
  }

  return true;
}