acai I assumed that the Atlas exported alongside the textures and materials would help reduce draw calls. However, I’m wondering—does having multiple textures and materials negatively impact performance? Would it be better to use a separate Unity Sprite Atlas to combine all the Spine 2D textures instead?
Draw calls will be combined if they use the same texture, i.e. atlas page texture. Please check whether you can change your skeleton's atlas pack settings in the Spine Editor to export a single larger atlas texture instead of resulting in 3 separate atlas pages, e.g. by increasing the maximum width and height or using Polygons packing mode to pack attachments more tighly.
Using Unity Sprite Atlas follows the same rules, draw calls can be batched if they use a single atlas page texture. So you should export the Spine atlas textures as desired in the first place, packing multiple complete atlas pages together via Unity's Sprite Atlas makes little sense.
acai Also, I need to export Spine 2D in binary format to be compatible with Unity's plugin, Adventure Creator. I'm not sure if I can use the CLI for that.
Skeletons should always be exported in binary format instead of .json format for production. This has nothing to do with the separate .atlas.txt atlas description file.
