I once used single bicubic Bezier patch to software compensate for optical distortion. Worked quite well, better than my previous attempts. Before that I made

I once used single bicubic Bezier patch to software compensate for optical distortion. Worked quite well, better than my previous attempts. Before that I made user mark optical center (in my hardware usually quite far from picture center) and edit radial distortion function. That’s when I learned these details about Bezier patches. I needed to calculate them a lot, in pixel shader that distorts some images, in vertex shaders for calibration grid, and in a few other places, that’s a complex product with my software running both on PC and embedded.