Yeah, waiting for new mechanim features in 5 seems like the most logical approach at this point. I'm trying to resist putting time into building my own system right before a better one becomes more easily possible.
On the subject of forward facing meshes, I feel like I should be really clear (not sure how well I'm communicating, I only slept a few hours last night...) What I want is for the meshes that get created in SkeletonRenderer to all be facing the same direction, rather than a mixture of front faces and back faces with cull off used in the shader. The main reason being that all the advice I've found about getting shadow receiving fully working on backfaces in unity has simply said "don't use backfaces." It also seems to fix some issues with the current deferred lighting and with projectors as well. Spine anims with projectors are cool!
Anyway, doing this for regular quads is easy
if you rearrange the order of the quad vertices so you're going counter clockwise instead of clockwise, backfaces become frontfaces. Then all you have to do is flip the UVs*. Doing this for mesh attachments seems like more a challenge, but I haven't really dug into the mesh attachments rendering code enough to say what the difficulties actually are. I think it just looked complex :p
*You also have to take into account attachments which are rotated in the atlas, which meant I had to add a bool field to another class, if I remember right. If anyone popping in here wants the non-mesh attachment code, let me know and I'll post it.
