and with this way (from here : viewtopic.php?f=3&t=1409) , we can do whatever we want
we can swap armor pieces even if they need different frames in animations :

slot: head
   skin placeholder: head1
      region attachment: doghead1
   skin placeholder: head2
      region attachment: doghead2
   skin placeholder: head3
      region attachment: doghead3

This software is definitely amazing, thanks a lot Esoteric !!!

Hi Nate and thank you for your help !

It's much more clear now with your explanation.
We' ll try to use 1 slot per bone and put in the 5 images of each armor set evolution, and use "setAttachment" method from the skeleton to change the image (region attachment) of the bone.
As you watch in this example (viewtopic.php?f=3&t=1131) :

RegionAttachment attachment = new RegionAttachment("newhead");
attachment.setRegion(atlas.findRegion("goblingirl/head"));
attachment.setX(0);
attachment.setY(0);
attachment.setScaleX(1);
attachment.setScaleY(1);
attachment.setRotation(0);
attachment.setWidth(64);
attachment.setHeight(64);
attachment.updateOffset();
skeleton.findSlot("right foot").setAttachment(attachment);

This seems very easy to use in this way.

I 'll give you a feed back when we tried in Unity or if we fail to elaborate it :$

But we greatly appreciate your help and advice, thanks a lot Nate !

Hello there,

Recently, i've posted a beginner question in this forum (viewtopic.php?f=3&t=1353) and Nate give us the solution.
I mean, we planned to use multiple atlases and swap them at runtime when the player changes a piece of gear.

But more we advance deep in Spine, more we realize that there are better ways to do this with spine's features : Slot and Skin
However, we fail to choose between these different features because we don't understand what's exactly the difference between them.

What we want to do :

We have a Character with 5 visual evolutions of his gear (each piece separately) , but keeps the same animation.
In game, player can loot a new evolution of a piece (e.g. new Shoulders) and wear it.

What are the Spine's features to use :

we have 3 choices :

1) use 1 slot by bone with multiple images within and swap the slot's image used at runtime ;
 Loading Image

2) use several slot by bone with 1 image in each slot and swap the bone's slot used at runtime ;
 Loading Image

3) use skin ? (it appears that skin is to change ALL images in one step, not only for 1 bone at a time?)

What's the difference between these 3 solutions?
wich would you use ?

Best regards.

Than you Nate for your very quick response !

Nate wrote

...
Yet another way is to use images that are all the same size, attach one set of images in Spine and note the position of the bone that the image is attached to. Next you make an alternate set of images keeping in mind that the bone position. Then you can pack all the images in the same or different atlases. at runtime you can programmatically create attachments for the images. You use the set of images you attached in Spine and just change the texture region.

It's exactly what we want to
With this method, we could swap each piece of armor individually.

Hi Everybody

Recently, we decide to use Spine in our pipeline and this software is very powerfull and easy to use ! Big Thanks to Esoteric Software !
But we discover it step by step and we have a big beginner question :

In spine, is it possible to use images from an atlas created in an external software, not with the included "texture packer" ?

In our project, we have a character with 5 evolutions. For each evolution, the clothes of the character change but the animations still the sames.
To do that, we planned to make 5 atlas (1 for each evolution) and "simply" swap the texture of the ingame character .
But the 5 atlas must be "the same": for example, the "R_upperLeg" piece in the atlas 1 must be exactly in the same place that the "R_upperLeg" piece of the other atlases.
To do that, we planned to make the atlas manually in an external software.
Maybe it is better to do this with the "skins " of Spine ?

Best regards.