Initial release of this tool for upgrading to pack format 16 for Minecraft 1.20.2.
The migrations automated here are not exhaustive, so some manual work may still be required. See the release changelog for more information. The changes automated by this tool include:

• All textures containing multiple sprites in a sheet for GUI have been split into individual sprites under textures/gui/sprites
• All sprites in the realms namespace have been moved into the minecraft namespace
• villager2.png has been renamed to villager.png
• icon/trial_available and realm_status/expires_soon sprites are animated with .mcmeta declarations instead of individual sprites

Only the assets/minecraft/textures/gui and assets/realms/textures/gui folders are affected. Will not directly modify your pack, but outputs the new format into the specified output directory.

Usage

An installation of Java 17 or higher is required to run the tool.

Command-line arguments: <input dir or zip> <output dir> [<leftover dir>]

• input dir or zip is the root of your resource pack (directory or zip containing an assets directory)
• output dir will be filled with all processed texture files
• leftover dir is optional location that will be filled with copies of source images with added highlights for areas that were migrated
  • The highlighted areas were processed by the tool and are used by the Vanilla game, the rest is not required in the pack