[bitwize]

Even so, the effects of these bugs are interesting enough to give names to. I remember some glitches in Sonic the Hedgehog 1 through 3 I called "The Valley of the Shadow of No Background" and "The Valley of the Shadow of No Sprites". The latter of which was caused by an integer coordinate wraparound that caused the game to draw the tile map scenery from your location modulo N, but not populate it with game objects because the coordinates didn't match. As a result, things like loops only half-worked, and the corkscrew things from Emerald Hill Zone didn't work at all -- because invisible objects triggered the movement mechanics specific to those scenery bits.