Debugging and save games

So a bit of self promotions to start (it is a blog, after all!). As part of the Quaddicted Advent Calendar, I made a short Christmas themed map-hack called In Small Packages. The trick behind it was to take a save game from e3m6, and then load it into a text editor and make extensive edits. The save game is essentially just a text file listing all the entities in the map, plus a little bit of extra info to restore all the global variables etc. Changing values on entities is akin to performing a map hack, except you can change values normally set by the spawn functions. What’s the connection to debugging? Read on…