Watch the pen draw. Turbo mode (shift-click the green flag) is recommended. The variable "e" is which effect to use for color, "e2" is which effect to use for shade.
Added fast mode and moveable center. IMPORTANT: Only e and e2 values of 1 are determined by the center. Check out the remix by eiim7! (some more effects for color/shade) http://scratch.mit.edu/projects/10127990/
