This is a write-up of the polygon renderer used for the Mega Drive demo “Overdrive 2” by Titan, released at the Revision 2017 Demoparty. As the Mega Drive can only display tilemaps, not bitmaps, and does not have the video memory mapped into the CPU address space, this turned out to be an interesting problem. If you have not seen the demo yet, I recommend watching it before continuing. You can fin