in sim/simulator.ts [30:38]
constructor() {
super();
this.bus = new EventBus(runtime);
this.element = <SVGSVGElement><any>document.getElementById('svgcanvas');
this.spriteElement = <SVGCircleElement>this.element.getElementById('svgsprite');
this.hareElement = <SVGCircleElement>this.element.getElementById('svgsprite2');
this.sprite = new Sprite()
this.hare = new Sprite();
}