internal coloring of the Mandelbrot set.

This is my coloration and rendering method for Mandelbrot set related fractals. Rather than base coloration on iteration number, I took the last iteration, (in this case I think it was iteration 20) and mapped hue and saturation to its x and y values. rather than use scanlines, I am using an Archimedes spiral to test each point. use slider a to change the power each iteration gets raised to in each iteration. It even works with negative values! If anyone has Ideas on how to speed up the rendering process, please let me know.