This is an animated floating cube displayed on an OLED display.
The graphics card is Quazar olded display. The file liboled.c is derived from the oled.s code published by Sam Coupe.
Most of the code in cube.c comes from 2 sources, Graphics Gems 1st edition, and for the line drawing code Wikipedia, Bresenham's line algorithm. The ramainder is code converted from an old floating cube line art program that I wrote about 10 years ago.