Tons of Draw Calls

Bystander

We are using Unity and EZGui along with Spine. We use it to animate enemies walking in our tower defense. Every enemy created adds 2 draw calls. We have a single material for all of the enemies and are using the skins to give each enemy a different look. Without spine our game has 5 draw calls. With spine, we get anywhere from 20 - 50 draw calls depending on how many enemies are on the same screen. How do we get spine to one draw call? Is it possible?

Thanks.

Bystander

Nate

Unity should do dynamic batching automatically. If you draw a Spine skeleton, then something else, then another skeleton it will result is more draw calls. Does your atlas have multiple pages?

Pharan

I think scaling and/or rotation on the GameObjects holding the meshes causes batching to break in Unity.
You'll need to confirm.

@Nate, it's kinda rare to control the draw order manually in Unity like that. I think draws are ordered according to the shader's "queue" tag and some combination of distance from camera. And then among things with the same queue tag, it's kinda unpredictable. There's probably some logic in there but I never really looked into it.

Bystander

@Nate, We currently only have one atlas, so one page.
If we were to put all our characters in a blank scene in Unity, should I be receiving one draw call or multiple per character?

Pharan

It should be one batched draw call for all characters that share one atlas, but only up to a point. There's that vertex count limit it talks about in the help article.

Again, check if you're scaling or rotating your GameObjects and confirm if that affects the batching.

Bystander

We are only scaling one of the GameObjects so we expected to see any extra draw for that character, none of the other characters are being scaled or rotated.

Does dynamically instantiating the GameObjects (Characters) affect the draw calls?

Pharan

Instantiation at runtime shouldn't affect batching. I do it all the time.

Can't imagine what else would be causing batching to break. The help article mentions the use of multi-pass shaders and stuff, if that applies to you at all. If you're just using the Skeleton shader that comes with Spine, it shouldn't be a problem.

Strange that I haven't come across this batching issue while using Spine's system.

... are you using just one material asset for the skeletons you intend to batch?

Bystander

Thanks for the help so far Pharan.
We seem to have found the problem. We have all our spine characters on the Spine Atlas and the rest of our sprites/environment images on another atlas. Unity adds extra draw calls when images from each atlas are in front or behind each other.

Is there a way to go about combining the atlases?

eseStas

Good afternoon. Faced with a similar problem , which is described above . Could you suggest as a solution to this problem there ?

Pharan

Can you open a new topic and describe your exact problem?
I can point you to some links to better understand the problem above (it's been 3 years) and a lot has changed both in Spine and Unity.

eseStas

I created a new topic Draw calls unity with spine