Ah. Thanks, Nate! That's good to know about GPU behavior.
On the topic of the best skeleton setup I need though:
Separate skeleton per direction in something like, say, an 8-direction sprite like an old Zelda-like game or Ragnarok Online, would make sense, albeit needing some extra code and a few more json files.
But I'm talking about momentary changes in perspective for certain body parts, like an entire arm, or a foot, or a momentary change in perspective of all parts. Like imagine a character in a platformer or fighting game, where the character does a medium punch or a spinning move, and the footwork requires a pivoting leg and pelvis, and the torso twists and the arm ends up in 2 or 3 other directions, foreshortened towards the camera, then side, then away, in sequence in one motion. (Shiu probably knows about this in detail.)
It's certainly just another paradigm in the middle of a continuum between zero recycling (frame-by-frame) and zero swapping (super-pure-semantic skeleton/modern 3D animation).
But it's something that can already be done in Spine with its inherent flexibility. It's just that it's really tiring without the ability to hide and show multiple bones/slots.
