var x=Math.min(this.start.x, this.control.x, this.end.x); var y=Math.min(this.start.y, this.control.y, this.end.y); var w=Math.max(this.start.x, this.control.x, this.end.x)-x; var h=Math.max(this.start.y, this.control.y, this.end.y)-y; return { x:x, y:y, width:w, height:h };