DrawableCircle - taken from https://github.com/AlphaGit/random-javascript/blob/90e6540100631e1a3ae590c3bde4a21b74f7abd9/arkanoid-canvas/arkanoid.js

DrawableCircle.js

//DrawableCircle: DrawableEntityBase
DrawableCircle.prototype = Object.create(DrawableEntityBase.prototype);
DrawableCircle.prototype.constructor = DrawableEntityBase;
function DrawableCircle(drawingContext, color, radius, centerX, centerY) {
    DrawableEntityBase.call(this, drawingContext, color);
    var self = this;
    self.radius = radius;
    self.centerX = centerX;
    self.centerY = centerY;
    
    self.draw = function() {
        self.ctx.fillStyle = color;
        self.ctx.ellipse(self.centerX, self.centerY, self.radius, self.radius, 0, 0, 0, false);
    };
    
    return {
    	draw: self.draw
    };
}