code: function(x, y) {
          var radius = this.radius,
              deltaX = this.x - x,
              deltaY = this.y - y;
  
          return deltaX * deltaX + deltaY * deltaY < radius * radius;
      }
docs: @
  #.containsPoint
  @comp Crafty.circle
  @kind Method
  
  @sign public Boolean .containsPoint(Number x, Number y)
  @param x - X position of the point
  @param y - Y position of the point
  
  Method is used to determine if a given point is contained by the circle.
  
  @example
  ~~~
  var circle = new Crafty.circle(0, 0, 10);
  circle.containsPoint(0, 0); //TRUE
  circle.containsPoint(50, 50); //FALSE
  ~~~