Merging skeletons?

ElPresidente

I have 2 spine projects, in each project there are 2 characters. (project 1 character A and B, project 2 character C and D). I am trying to combine character A from project 1 and character C from project 2. To that end I have deleted all bones and containers/slots of characters B and D (the ones I don't need), re-named all bones, containers and individual images and animations, saved those projects under new names.
Then I exported both characters and copied the individual body part images to the other projects folder.
Now when I import a character into the other project, everything imports - the imported character appears as it should be, parts visible in proper starting pose, but the bones all end up messed up, bunching up in a star-like configuration.

Misaki

ElPresidente The exact reason why the bones are arranged in a star-like configuration is unclear, but as Spinebot mentioned, it is possible that the constraints are not set correctly.
Unfortunately, constraints cannot be moved between skeletons. Therefore, even if you move the bones, the constraints will not be transferred, so it may not be possible to reproduce the previous setup or animation with just these steps. The properties of each constraint can be copied by selecting it in the tree view and pressing Ctrl+C, so you can use them for the merge process. (We understand that this is a cumbersome process, but moving items between skeletons is very complex, and there are currently no plans to implement constraint movement between skeletons in the short term).

Spinebot

When merging skeletons from different projects in Spine, it's crucial to ensure that all elements such as bones, slots, and images have unique names to avoid conflicts. The issue you're experiencing, where bones end up in a star-like configuration, often occurs due to discrepancies in bone hierarchy or transformations between the two projects. To resolve this, you should carefully check the bone hierarchy and ensure that the transformations (position, rotation, scale) are consistent between the skeletons before importing. Additionally, make sure that any constraints or animations are correctly set up and that the import process respects these settings. If necessary, you might need to manually adjust the bone positions after import to align them correctly.

ElPresidente

Misaki So should I remove all contraints on the character I want to import, export character, and then re-create them after import?

ElPresidente

I did re-name all bones and everything before import, so bone names shouldn't be an issue. All bones on one character are A_boneXX on one character and on the other B_boneXX... except for the root, but you're not supposed to change the root?
As for the transforms, I'm not sure what exactly is meant here by "making them consistent", as every bone by default has it's own rotation, position and scale.

Misaki

ElPresidente You don't need to remove constraints beforehand, in fact I think it's better to keep the properties so they can be copied later. You should be able to restore the original setup by recreating the constraints with exactly the same properties in the skeleton you are merging to.

ElPresidente

The only constraints are 4IK's for the hands and legs. All the bones end up re-arranged to all come from the same point, which seems to be the hips/character root

Misaki

ElPresidente Ah, from what you've described, it sounds like the root bones of the two skeletons are not named consistently, which may indeed be the cause of the problem. Try to make the names match exactly, including the root bone name.

I should add, when importing, white outlines can be seen around connecting body parts, as if 1 white pixel was added. I'm not importing/unpacking the atlas, just copying the images directly to the other project folder.

This is very strange. Please send us a Spine project that reproduces the problem via email so we can check it out: contact@esotericsoftware.com
Please include the URL of this forum thread in the email so we know the context. Then we can take a look at what's wrong.

ElPresidente

I should add, when importing, white outlines can be seen around connecting body parts, as if 1 white pixel was added. I'm not importing/unpacking the atlas, just copying the images directly to the other project folder.

ElPresidente

You msiread, i DIDN'T re-name the root bone. Both are called root. Tough all the other bones, I did. However, I will have to double-check.

That said, by importing a proejct into a project (so there are two skeletons) and then draggin and dropping the character root to the other skeleton root, then drag-dropign all the slots, I did manage to move over everythinng, with bone positioning nad image poisitioning perserved.
HOWEVER, all weigting/binding is gone. Not I'm not sure if things might be perserved if I did it in a different order. Not sure if I moved the bones first or the slots (I think bones).

Misaki

ElPresidente I apologize for the misunderstanding. Unfortunately, I don't think we can give you any further advice without actually seeing your Spine project. I will check the details as soon as we receive your Spine project.

ElPresidente

This is very strange. Please send us a Spine project that reproduces the problem via email so we can check it out: contact@esotericsoftware.com
Please include the URL of this forum thread in the email so we know the context. Then we can take a look at what's wrong.

I will try to re-create the problem in a new project next week, won't be able to do it now. The current project is not suitable to be sent for various reasons.