This is a simple modification of the last program which creates a kind of
rudimentary 4-way kaleidoscopic effect.
In the last program, for each pixel, we computed a random color c, and a random
set of 2D coordinates x and y. In this program, we use this information to
paint 4 pixels of the same color at the following positions:
x,y
width-x,height-y
width-x, y
x, height-y
UPDATE: The source code below now contains an Actionscript 3 version, and a Flash 8 (bitmapped) version, in addition to the original Flash MX code.