基于HTML5 Canvas實現雨滴效果： Rainday.js

一個簡單的腳本來模擬雨滴落在玻璃表面效果。rainyday.js擁有功能可擴展的API，碰撞檢測，并很容易用自己不同的動畫組件實現擴展。Rainyday.js是一個純的JavaScript庫，用到了HTML5的特性，所以都支持大多數現代瀏覽器它。

How to use:

var engine = new RainyDay({
    element: image,         // Image element
                            // This value is required
    parentElement: someDiv, // Element to be used as a parent for the canvas
                            // If not provided assuming the 'body' element
    crop: [0, 0, 50, 60],   // Coordinates if only a part of the image should be used
                            // If not provided entire image will be used
    blur: 10,               // Defines blur due to rain effect
                            // Assuming 10 if not provided
                            // Use 0 value to disable the blur
    opacity: 1              // Opacity of rain drops
                            // Assuming 1 if not provided
});
engine.rain(
    [
        [1, 0, 20],         // add 20 drops of size 1...
        [3, 3, 1]           // ... and 1 drop of size from 3 - 6 ...
    ],

    100);        </pre>



項目主頁：http://www.baiduhome.net/lib/view/home/1406863000218