Let's say I'm packing some masks with my character regions. I believe I can use the OnPostProcessVertices to write my custom mask UVs. However, it's entirely possible the atlas packer will place the mask on a different page. If that happens, is there a way I can tell spine to bind the other page? Does spine bind all of the pages for an atlas or does it only bind the pages in use? I assume it can bind more than one page since a skeleton might have a head on page 0 and an arm on page 1, etc.
Spine Unity atlas texture pages question.
In Spine, when you have multiple atlas pages, the runtime will bind the necessary pages as needed. If your skeleton uses attachments that are spread across different atlas pages, Spine will handle binding those pages during rendering. This means that if your mask is placed on a different atlas page than your character regions, Spine will bind both pages when rendering the skeleton, provided that both are in use by the skeleton's attachments. However, keep in mind that having attachments on different atlas pages can lead to more texture binds, which may affect performance. To optimize, you might consider organizing your assets so that frequently used attachments are on the same atlas page.