As the basic framework is done, I started researching for interesting looking formulas that could be used to generate the inner design of the stained glass. The one that looks really promising is Super Formula.
The Super Formula, also known as Super Shape is the generalization of the Super Ellipse. It is used to generate some very interesting and complex shapes using 5 different parameters.
I created a small program on Processing to test whether Super Formula could be a viable choice for this project.
Here are some examples of what could be achieved with it:
Although it is possible to generate some beautiful figures with only one formula, it has a major drawback. I could not find a way to draw part of the figure that would start at, for example, (x1, y1) and would end at (x2, y2) because there is no such combination of parameters that would allow to predict the end point of the figure / curve, or it is not a straightforward solution.
Generative Design Of Stained-Glass Windows 