This project is a 4" diameter ring of APA102C "super LEDs". These LED devices are RGB LEDs with a SPI like interface (CLK and Data). The cool part is that they can be easily daisy chained to form large displays. The videos below show 3 rings daisy chained together and driven via a Teensy 3.2. As you can see in the files, this project shows how to make complex board shapes in CircuitMaker
Here are some good resource for the APA102:
You can get screens, strips and individual units.
Adafruit sells these LEDs in single units and on a flexible strip. You can also go to Aliexpress and find them much cheaper. I elected to purchase several reels of devices. They are about 1/4 the cost of the US based distributors.
I have personally ordered all of the variants. Everything was well packed and sealed from the Aliexpress vendors.