Node constructor

Node(num i, num x, num y)

Implementation

Node(this.i, this.x, this.y) {
  // previous and next vertex nodes in a polygon ring
  prev = null;
  next = null;

  // z-order curve value
  z = null;

  // previous and next nodes in z-order
  prevZ = null;
  nextZ = null;

  // indicates whether this is a steiner point
  steiner = false;
}