Why does Canvas.BuildBatch happen at random and how can I avoid it during runtime?

Unity Engine
1

Profiler shows that the following is taking around 3 seconds and the game freezes for the whole time:
Canvas.BuildBatch → Canvas.GenerateBatchedMesh → Canvas.FillBatchMesh

It happens once at random time during the first 2-3 minutes of play.

How can I avoid this (any tips?) or how can I force BuildBatch at the beginning of the game?

2

building the batch happens when something on any of the UI elements changes, so my guess is one of you objects is moving/ changing color/ something else randomly during the game.

It does force a BuildBatch right at the beginning otherwise you’d see no UI.

3

I don’t seem to change anything, except just one animation which moves the position of the popup, the anchors and everything else staying the same.

Can it happen if a text label is updating every frame?
I also destroy a panel from the canvas at the beginning of the scene, might that be the reason?

P.S.: This hiccup happens only on iOS, it does not happen on Android

4

I am sure that nothing in the UI changes at the moment of freeze. Tested without destroying the panel, same result. Is there a reason why BuildBatch might take so long?

5

If anything changes then the batch would need rebuilt. So yes changing the text everyframe if for some reason the verts arnt return the same (although it should) it would cause a dirty on the batch.

It takes so long likely because it is calculating a lot of overlaping elements. we are going to improve this at a later point

1 Like
6

I removed all the UI elements, but the problem still persists. Been struggling with this problem for weeks now.
I reported it as a bug with more information. If you’d like, you can check Case 649698.

7

Thanks we’ll take a look once it gets through QA

8

I’m also having a very similar problem at the moment. Was there any resolution to this issue?

9

was fixed way back then what are you seeing