The map cache folder normally contains saved information, including paths (along which units move), adjacencies and distances for every province in the game, as well as other details needed to build and use the map in-game. Using such a cache instead of a predefined database allows EU3 to deal with flexible maps and thus makes the game more moddable, and it is much quicker than recalculating the paths on every startup.
The Importance of Clearing the Cache
After changing, adding or removing provinces, the cache will have to be recalculated. This means that it is often necessary to manually clear the cache after switching mods or installing a new patch. Failing to do so will result in strange behaviour, such as:
- Messed up colonial distance
- Naval patrols reaching all over the world
- Odd colonist/merchant travel times.
- Possible out of sync errors in multiplayer games for you or others (Note that you can cause other people who do have their map cache cleared to go out of sync if you do not have yours cleared so it is especially important to clear your cache in a multiplayer game).
This can be confusing for players, who have often reported "colonial distance bugs". Paradox does not appear to regard this as a bug; it is up to the player to clear the cache in such situations. However patch 5.1 comes with the correct map cache included, so there is no need to renew the cache unless a problem is experienced.
To manually clear the cache
- Navigate to the
[your EU3 folder]\map\cache\directory (folder). Select all files and directories there (Ctrl-A, or Command-A on Mac) and delete them.
- If you're using Windows Vista, 7, or 8, also click on the 'Compatibility Files' button at the top of the directory. This will take you to your virtual store folder (which is used by the game if you don't play EU3 in admin mode. Delete all of the files here as well. To manually find your virtual store folder go to
C:\Users\NAME\AppData\Local\VirtualStore\Program Files (x86)\EU3\map\cache
- After deleting the files, start your game up, and the cache will be recalculated based on the current game files. Note: You will not have the correct checksum yet.
- Restart your game after the map cache has been recalculated and you will have the correct checksum.
Note that recalculating will take some extra time, it could take a few minutes longer than usual to fire up the game.