Port S1 Rigged Model to S3 Rig
This tutorial is now deprecated in favour of 2kpr's rebone tool.
If you use a body part model from season 1 in an outfit that is rigged for season 3, or vice versa, the result will look very silly indeed. This is because IOI altered the skeleton over the years.
We can fix that by converting the model, you won't need any Blender knowledge for this because we're only going to swap some depends around and rebuild the PRIM. You will need RPKG Tool and comfort in using it, this procedure is a bit advanced so it will be assumed you are a seasoned user of the tool.
This should keep cloth physics intact, as well.
Prep an RPKG archive to work in
We will be doing work in RPKG Tool itself, and we don't want to overwrite any existing chunk files, not only because it's a really bad move to overwrite vanilla archives but also because saving the chunk file would take way too long. So begin by extracting the PRIM you need to convert and its BORG depend to a folder on your computer.
For the purposes of this guide we will be converting Ezra Berg's flannel shirt which is 00B618F2DCD237B2.PRIM with its bonerig 003D8C4FB5037FD2.BORG.
Extract a S3 rig as well, we can recommend 0017416135CF879C.BORG which is used by all of 47's season 3 outfits.
With all 3 files in the same directory, plus their .meta files, in RPKG Tool click Generate -> Generate RPKG From Folder. Select the folder where you put the 3 files and their corresponding .meta files. You can select the same folder again to spit out the generated .rpkg in the same folder.
Then, in RPKG Tool, click Import -> Import RPKG File and select your newly minted RPKG archive.
Step 1: Export model
Right-click the PRIM in the Resource View, nested under your new RPKG. Click Extract 00B618F2DCD237B2.PRIM to GLB file and make a new folder. Name it something so you can understand that this is the original season 1 version, like shirt_s1. Export the GLB to this folder.
Step 2: Edit hash depends
With your PRIM selected in RPKG Tool, click Edit Hash Depends under Details on the right. Entry 0 with the flag 1F is the skeleton bonerig. Change this hash to 0017416135CF879C and click Save Changes to Hash Depends. Click OK on the popup and the RPKG will regenerate.
Step 3: Export model again
RPKG Tool will close your RPKG archive now that it's been regenerated. Go to the bottom of the Resource View and expand it. Find your PRIM again and click on it. You will note that the first depend hash has been altered to our new BORG. Once again right-click on the PRIM in the Resource View and click Extract 00B618F2DCD237B2.PRIM to GLB file and make a new folder. Name it something so you can understand that this is the season 3 depends version, like shirt_s3. Export the GLB to this folder.
Step 4: Overwrite meta files
Go into your shirt_s3 folder and enter the metas folder, nested inside. Copy the PRIM.meta and PRIM.glb.meta files and back out. Now enter your shirt_s1 folder, and its nested metas folder. Paste and overwrite.
Step 5: Regenerate PRIM
Go back to RPKG Tool. Click Rebuild -> Rebuild Mesh Primitives (PRIM) From Folder. Select the shirt_s1 folder. After a brief moment the RPKG Tool will report its success.
You can now enter the shirt_s1 folder, and go into the REBUILT folder nested inside. The PRIM file has been rebuilt and you can now use it in your mod. You can clean up the temporary RPKG you created and the rest of the files now.
It would be prudent to generate a new hash for this converted PRIM in RPKG Tool using Utilities -> Hash Calculator, so you don't overwrite the original. In this case, we can tweak the original IOI assembly path:
[assembly:/_pro/characters/assets/individuals/colorado/ezraberg/geometry/male_reg_ezraberg.wl2?/shirt.weightedprim](bodypart).pc_weightedprim
And simply append s3_rig to it:
[assembly:/_pro/characters/assets/individuals/colorado/ezraberg/geometry/male_reg_ezraberg.wl2?/shirt_s3_rig.weightedprim](bodypart).pc_weightedprim
This hashes to 00D6AAA15BD7069F, so that will be the hash of our new PRIM. Technically you can hash any length of text you want, but it's nice to follow convention, no?
