Here's my idea for this concept.A backup folder is created in osu! to store saved backups. A backup is basically a copy of the .osu, but the game is able to locate and move the file back into the folder through an ingame menu or by double clicking on it. A backup file can be made automatically, or by a button press. If it is done manually, then you can choose a custom name for the backup. The name has no effect on the file when it is imported back into the folder, it is just a way to catalog different backups of the same .osu.
Backups should not be active by default. There should be a global option to turn auto saving on automatically. This would save time for mappers who have a lot of projects. The most important option though is the one accessible through the editor. Checking it on will save a backup every x amount of time. Although peppy tends to not give us the extra functionality, but it would be nice if we could set the period of time it saves in the config. The global option will only effect maps that you own.
I know that this will be an issue in the future when it gets implemented. When the title/artist data gets changed, ask the mapper if he wants to update this information in the backups. There should be a way to connect the backup to the folder and the folder to the backup. I think it would be a good idea to have backups loaded when you edit a map, so that the player can import a backup at anytime. This will probably lose any unsaved/unbacked up data, so make sure to prompt the mapper about such issues.
woc, i'm looking at you to make this a reality.
This would save people who revert changes a lot and are prone to crashing a lot of time (me).
So most certanly it will be a cmd-tool, where you have to manually type in the folder names you want a backup history of.
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