This little demo draws some pretty patterns, then distorts them by poking at some VGA registers and drawing random mess on the screen.
It's of no use to anyone, but it looks fun for about 30 seconds.
Written using Borland C++ 3.1 under FreeDOS inside 86Box
I used WinImage to get files in and out of the emulated DOS machine's hard disk image.
Install all the stuff above, clone this repo, get it into your emulated DOS machine and then type
BC GLITCH
It should open the project, you can then compile and run it from the menu.