do (win = window, doc = window.document, exports = window) -> $ = (selector) -> doc.querySelector selector $$ = (selector) -> doc.querySelectorAll selector class Ball vx: 0 vy: 0 x : 0 y : 0 r : 4 angle: Math.PI * 360 color: '#c00' constructor: -> draw: (context) -> context.save() context.fillStyle = @color context.beginPath() context.arc @x, @y, @r, 0, @angle, true context.fill() context.closePat