Animation Frame Rate Drop and Lag

[CentrumGuy]

Check these before submitting:

• The issue doesn't involve an Unsupported Feature
• This issue isn't related to another open issue

This issue is a:

• Non-Crashing Bug (Visual or otherwise)
• Crashing Bug
• Feature Request
• Regression (Something that once worked, but doesn't work anymore)

Which Version of Lottie are you using?

Lottie 3.1.3

What Platform are you on?

• MacOS
• iOS

What Language are you in?

• Swift
• Objective-C

Expected Behavior

Smooth animations like in lottie version 2.0

Actual Behavior

Animations lag a lot (especially during other UIView animations). I've been using lottie 2.0 until a couple days ago (because I liked the old way Lottie used to work) until I came across a bug that caused Lottie 2.0 to crash. Since then, I've updated all of my animations to support Lottie 3.0 and things seem to be way more laggy now. Playing an animation while running other UI animations like changing opacity and size of a UIView using "transform" causes animation frame rates to drop. In general, things feel less polished and hurts my app flow. I'm sorry if this is a horrible description but I can't find another way to describe it. This might not even be Lottie's fault but I know something changed from the way animations were running in Lottie v2.0 to the way they are running now (using Lottie v3.1.3)

Code Example

N/A

Animation JSON

This happens on basically all Lottie animations.

[buba447]

Duplicate of #895

Im aware of the performance issues, but dont have the bandwidth right now to tackle them. The short of the long story is, swift overhead for memory management of structs is killing performance of the renderer and needs to be rewritten.

[superarts]

Hi @buda447, it's been a while; this rewriting hasn't happening yet in recent releases and still sits in TODO here. Any ETA for a fix please?

[kapsyst]

Any update on this? I'm experiencing similar lagging issues.

[Dianafadal]

I've been hoping to find answers as well. I don't think my character animation is using anything unsupported (aside from some object I had feathered which doesn't render anyways and I'll just take it out now that I know) but I guess the frames are dropping/skipping the WHOLE walk cycle when it seems perfectly fine in the render preview window. I haven't found much in terms of troubleshooting this issue...

[calda]

Today we released Lottie 3.4.0 which includes a new rendering engine powered by Core Animation (more details here). This new rendering engine has significantly better performance, and should resolve the performance issues folks have been encountering with the previous main thread rendering engine. Please try it out by setting the LottieConfiguration.renderingEngine feature flag, and feel free to report any new issues that you experience when using the new rendering engine.