Maya-Style Incremental Save Plugins

Maya has a really neat feature called incremental save where as you save your project a version history will be saved in an adjacent folder called incrementalSaves. I've often found myself wishing that other applications would organize incremental saving the same way that Maya did, so I've decided to start implementing Maya-style incremental save system in other applications I use.

Each folder in this repository contains an incremental save script or plugin designed to add Maya-style incremental saves to another application, as well as instructions for how to install it. Feel free to fork and submit a PR if you want to add an application that isn't supported yet! Make sure to read through the Behavior and Implementation sections though, as the purpose of this repository is to make incremental save behave exactly the same across all applications it's implemented for. You can also use the increment method in incrementaltools.py--it's designed to work with any software as long as you pass in the right methods.

Behavior

There are two main features in Maya's incremental save. The first is that if you save a file, its version history will be saved in an incrementalSaves folder in the same directory as filename.####.ext. However, if you open a file in the version history and save it, then the file you saved will become the new current version. Here's an example:

Let's say you have a file called test.ma. If you save the file, the original test.ma will be copied to incrementalSaves/test.0000.ma and then the new version of the file will be saved as test.ma. Each time test.ma is saved, a new version is copied to incrementalSaves.

Now let's say that you have three incremental saves: test.0001.ma, test.0002.ma, and test.0003.ma. If you open test.0002.ma and then save it, the original test.ma will be copied to test.0004.ma and the file you saved will become the new test.ma. Saving an incremented file is like rolling back to an older version.

This is what the directory structure would look like:

- test.ma
- incrementalSaves
	| - test.0001.ma
	| - test.0002.ma
	| - test.0003.ma
	| - test.0004.ma

Implementation

Here's the algorithm that I use for incremental saving. These steps should run when the incremental save operation is run. Code implementation is in incrementaltools.py:

1. Check whether the currently opened file is an incremental save of a different file. If the current file has a name of the form NAME.####.ext, is saved in a directory called incrementalSaves, and a file called NAME.ext exists in the parent directory, then the current file is an incremental save.
2. If the currently opened file is not an incremental save, copy the file to incrementalSaves/NAME.####.ext. Figure out the number to use by scanning the incrementalSaves directory and finding the highest current increment number, then adding one. If incrementalSaves doesn't exist, create the directory and copy the file as NAME.0000.ext. Once the old version is copied, run File > Save (or equivalent) to save the new version of the file as NAME.ext
3. If the currently opened file is an incremental save, copy the original file (NAME.ext) to the incrementalSaves folder using the same process as step 2, then save the currently opened file as NAME.ext.