text: class Ground {
    constructor(x,y,width,height){
       var  options={
        isStatic:true
      }  
      this.width=width;
      this.height=height;
      this.body=Bodies.rectangle(x,y,width,height,options);
      World.add(world,this.body);
    }
    display(){
      var pos=this.body.position;
      rectMode(CENTER);
      fill("brown");
      rect(pos.x,pos.y,this.width,this.height);
    }
  };