I like the idea of improving GPU fill rate, especially for this animated crowd I have. I think I discovered an editor bug in the process of adding these meshes after the fact. If the region attachment has a negative x scale, the resulting mesh is flipped on the Y axis and moved up in space to the original top border of the attachment's bounds.




I can work around this, but it's an extra couple of steps for however many of these I need to edit.
If I have an estimated 3 billion region attachments all sharing the same image in the atlas, will Spine just pack against the first mesh it finds for each? How do I copy mesh data to identical attachments?
Ah, yes the export works while stripping out like-for-like images. I got it to a point where I gave up on an export after 30 minutes, but prior to that it did work.
I do notice that meshes break when typing in scale numbers below 1.0f, and the mesh cannot be scaled back to 1.0 or above. You have to undo the action. They can be scaled with the mouse, however, but that also alters x/y transforms as a group.