text: class Cannonball {
      constructor(x,y){
       var options={
       restitution:0.8,
       friction:1.0,
       density:1.0,
       isStatic:false
       }
       this.r=40;
       this.body=Bodies.circle(x,y,this.r,options)
       this.image=loadImage("./assets/cannonball.png")
  
       World.add(world,this.body)
      }
      display(){
          var pos=this.body.position;
          var angle=this.body.angle;
          push()
          translate(pos.x,pos.y)
          rotate(angle)
          imageMode(CENTER)
          image(this.image,0,0,this.r,this.r)
          pop()
      }
  
       shoot (){
           var velocity=p5.Vector.fromAngle(cannon.angle)
           velocity.mult(20)
           Matter.Body.setStatic(this.body,false)
           Matter.Body.setVelocity(this.body,{x:velocity.x,y:velocity.y})
       }
      
  }