The XNA Platformer game ported to HTML5... as in wow (and you can get the source too. wow++)

David Rousset - HTML5 Platformer: the complete port of the XNA game to <canvas> with EaselJS

After a couple of hours coding with JavaScript, I’ve finally finished porting the XNA 4.0 Platformer game sample to HTML5/Canvas with the help of the EaselJS gaming framework. This article will provide you the game and the story of some of the questions I’ve asked myself while coding it. If you’d like to know how the game works, simply read the JavaScript commented code available at the end of this article. Please note that my main goal was to better learn JavaScript by writing pure JS code (with no form of dependency to the DOM) and to write a cross-browsers working game and cross HTML5 compatible devices when possible also.

You can play the game directly inside this iframe (left & right arrows keys to move & W to jump). Just press the “Start” button to launch the download sequence and the game itself.

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Holy cow... And it's even playable.