tripzilch

const CAPACITY = 8;

class QuadTree {
  constructor(x, y, w, h) {
    // the rect (x,y,w,h) defines the product of two half-open intervals: [x, x+w) × [y, y+h)
    this.x = x; this.xe = x + w;  
    this.y = y; this.ye = y + h;
    this.w = w;
    this.h = h;
    this.pts = [];