Map editing has been a huge part of Unearthed so far, and I end up getting a lot of questions regarding what exactly goes into the map-hacking process. The full explanation of the process involves a lot of complicated stuff including coding, palettes, pointer tables, etc. But in short, the map-editing process can be condensed into one word: TILES.
In Earthbound, a huge amount of 64×64 pixel tiles are arranged across the map screen to form the different areas within the game. Above I have a close-up of a specific area of the game within PkHack’s map editor (click here to see the entire game map). The top part of the window is the map screen itself, while the bottom is a palette of tiles that can be used with the current tile-set (in this case, Winters). Different tile-sets have different types of terrain, buildings and scenery built into them. The map editor lets you move these tiles around to edit old areas and create new ones.
Each 64×64 pixel map tile consists of 16 8×8 pixel mini-tiles. In the map tile editor you can draw out new mini-tiles, change the colours used in a specific tile-set, and arrange the mini-tiles to form new map tiles for use in the map editor. This is a painstaking process but is necessary for advanced map hacking.
If you really have a lot of free time, you can edit the map tile properties as well. These properties are represented by a grid of numbers and dictate what part of the map can be walked on, as well as a plethora of other things. Messianic was kind enough to compile a list of all the different tile-set properties used in Earthbound. Check it out if you are curious!
This last picture is an example of what happens when you heavily edit a tile-set without moving things around in the map editor. This is basically where I am at with my hack at the moment, and I’ll start editing the maps together into something cohesive shortly!