Tree map

I built a slice and dice treemap in quartz that staticly supports 8 values and will graphically represent the data in ratios of individual value over collective total. What I would like to do now is repurpose the code to use an iterator that would step through a structure of values and generate the treemap instead of having to hardcode each and every member. The problem Im running into is the position of the bars is dependent of the previous block formula results. Im at a lost as to where to continue, Ive attached the treemap qtz. If anyone could assist and push me in the right direction, I would be greatly appreciative.