Fixed stained glass technology has been around for ages, its one of the most beautiful art forms created, however, what is a programmable stained glass could be made using subtractive color techniques, by still being solar backlighted? Here is a 3D model of how such mechanism could work, by hydraulic analog pixels filled with pure cyan, magenta and yellow oil. Pixels are around 10-30cm, and each pixel unit consist of three thin glass layers one behind the other, containing these three oils. The proportions of oils in each glass panel can then produce any visible color. This means is still stained glass, but can be generative, it can move, thus providing the appropriate technology for the first cathedral dedicated to the Mandelbrot set. But to make this a physical reality funds an a few years to build will be needed, but it will be worth it.