Mandelbrot viewer on html5 canvas.

Experimentations with modern browsers, html5, performance, and the beauty of fractals.

Todo

• switch between Mandelbrot and julia sets easily
• use web workers with Transferable objects to speed it up (http://updates.html5rocks.com/2011/12/Transferable-Objects-Lightning-Fast)
• profile optimal number of workers
• add pretty color schemes
• switch to use BigDecimal intelligently when zooming in and numbers become close together
• animated transitions??
• more fractals! 3d fractals?
• use pushState() to track zoom level and allow history navigation.
• I think we can speed up the selection-drawing by only doing a clearRect() on the region we
  need to. That should eliminate the gap between mouse and rectangle when dragging.
• add “slow-mo” view, to show the Mandelbrot set being constructed one iteration at a time.
• draw Mandelbrot set off the UI thread, so it does not block loading of the whole page
• dashed selection line
• draw Julia set more accurately, cf. wikipedia
• do not do colorization in compute(), so that it is possible to change color schemes without re-computing
• fix rectangle-drawing code, sometimes it ‘sticks’ and does not work
• make zoom do something sensible when there is no selection
• show a ‘waiting’ cursor on blur/sharpen/etc., so it is obvious when done.
• anti-alias to smooth out color transition (average of 9 pixels)