Yes, you&#x27;re right.<p>Shaders are small chunks of code that run on the GPU. Usually they&#x27;re used to do things like process geometry (lots of matrix multiplications), map triangles to pixels (lots more matrix multiplication), and things like that. Vector and matrix math, with some logic, sometimes.<p>What appears to be going on here is that the entire state of the machine, including IO, registers, and memory, is getting mapped into textures. The shader then processes the pixel values from those textures through a series of conditionals to output a new state into a new texture. Next frame, the process continues.<p>Pretty nifty, and a glorious abuse of the incredible compute power available in modern GPUs. I ran it on a cheap integrated Intel GPU and it was rock solid at 60fps.