Negative font help


Im working on a typeface for schoolwork that is best described as a negative font, i have 5 classes, on positive, one negative, then positive that has bite taken off from both sides, bite taken off only from right side, and last one bite taken off from left side.

I have done a simple script that substitutes every other letter to negative when there are 2 positive letters next to each other. Now what i want is to get the first letter always be all positive or bitten off by right side depending if it has a round letter next to it, or not. and middle ones as well totally negative letters or bitten off both sides. My time is running out, and no help what so ever. Well, ask me anything, if you did not understood.

Sincerely, Nele