// https://github.com/CodingTrain/QuadTree

// https://thecodingtrain.com/CodingChallenges/098.1-quadtree.html

// https://thecodingtrain.com/CodingChallenges/098.2-quadtree.html

// https://thecodingtrain.com/CodingChallenges/098.3-quadtree.html

​

let particles = [];

​

function setup() {

  createCanvas(600, 400);

  for (let i = 0; i < 1000; i++) {

    particles[i] = new Particle(random(width), random(height));

  }

}

​

function draw() {

  background(0);

  let r = new Rectangle(0, 0, width, height);

  let quadtree = new QuadTree(r, 4);

  for (let p of particles) {

    p.move();

    p.setHighlight(false);

    const point = new Point(p.x, p.y, p);

    quadtree.insert(point);

  }

  for (let p of particles) {

    let c = new Circle(p.x, p.y, p.r * 2);

    let points = quadtree.query(c);

    for (let point of points) {

      let other = point.userData;

      if (p !== other && p.intersects(other)) {

        p.setHighlight(true);

      }

    }

  }

  for (let p of particles) {

    p.render();

  }

​

​

​

}