java script drawing into buffered image

I want to 开发者_运维知识库draw a bitmap into buffer and create a bitmap using javascript. ideally i should create a bitmap by drawing lines, rectangles and stuffs like that, and paint into the screen when required. Thanks for replying and giving some code hints.

regards

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you can do it with canvas:

https://developer.mozilla.org/en/drawing_graphics_with_canvas