text: class Link {
      constructor(bodyA, bodyB) {
          var lastlink = bodyA.body.bodies.length - 2;
          this.link = Constraint.create({
              bodyA: bodyA.body.bodies[lastlink],
              pointA: { x: 0, y: 0 },
              bodyB: bodyB.body,
              pointB: { x: 0, y: 0 },
              length: 10,
              stiffness: 0.8
          });
  
          World.add(world, this.link);
      }
      dettach() {
          World.remove(world, this.link);
      }
  }