From Trammell Hudson's Projects
I wanted to experiment with pentagonal pyramid diffusers for LEDs, so I wrote a program that generates the flat-pack version of them to laser cut. There is too much trig, although the SVG rotating reference frames makes it fairly easy.
I also wrote a quick OpenSCAD design that generates a 3D-printed diffuser for the Adafruit 24-pixel ring. It's thing:526462 if you want to print your own.