oCanvas对象化 Canvas
oCanvas 可以帮助你很容易的在 HTML5 的 Canvas 标签上创建对象，并且创建这些对象的动画。支持包括 IE9 以及更新版本和其他包括 FF、Chrome、Safari 和 Opera 浏览器。
该库包含 9 部分：
oCanvas Object: which represents the HTML5 Canvas element itself, where everything will be built.
Core: is the main instance which defines all other elements.
Display Objects: representing the main predefined geometrical elements (lines, triangles, rectangles, etc.).
Background: stores settings of object surface.
Canvas.Timeline: facilitates the creation of loops for moving objects.
Events: capturing the events that can occur with the keyboard, mouse, and touch.
Scenes: We can group objects into independent "frames".
Animation: Lets you create short animations for each object.
Draw: Module that allows you to clean or repaint the scenes.
示例代码：
function createAnim() {
//Block 1
var tela = oCanvas.create({
canvas: "#canvas",
background: "#ccc"
});
//Block 2
var quadrado = tela.display.rectangle({
x: 25,
y: 25,
width: 20,
height: 20,
fill: "#0aa",
velocX: 4,
velocY: 4
});
tela.addChild(quadrado);
//Block 3
tela.bind("click tap", function() {
quadrado.x = tela.mouse.x;
quadrado.y = tela.mouse.y;
});
//Block 4
tela.setLoop(function() {
quadrado.x += quadrado.velocX;
quadrado.y += quadrado.velocY;
quadrado.rotation++;
if ((quadrado.x <= 0) || (quadrado.x >= (tela.width)))
quadrado.velocX = -quadrado.velocX;
if ((quadrado.y < 20) || (quadrado.y > (tela.height - 20)))
quadrado.velocY = -quadrado.velocY;
}).start();
}