Javascript library for drawing multi-layered graphics using <canvas>. Uses multiple canvas elements layered on top of one-another using css. The Javascript code to redraw each canvas element is only called when needed. In cases where there is a complex but static layer (like a background layer), efficiency is dramatically improved.

As a basic demonstration of the reduced CPU usage, compare http://b3nj4m.com/canvas_test.html with http://b3nj4m.com/canvas_test_slow.html.