Timeline update capsule halfheight crash, unless

So this is a weird one. I have sliding in my game (you can see movement of it here - https://www…com/watch?v=XKEXf4y_OrM), and recently noticed I’m getting a crash some of time that I slide. I’m not 100% sure if this crash came in in 4.8 or if I just never noticed before because I didn’t slide much, but I’m thinking 4.8. After a long time messing around, I’ve narrowed it down to this:


You can see here that I have a timeline that lerps player character’s collision capsule half height to be smaller (so we can slide under stuff). Not seen in this screenshot, we have another timeline that does same thing but lerps either back to a standing position or into a crouch if there’s no room to stand.

Either one of these timelines will crash (entire editor) on their first Update sometimes:
-never on first slide
-when I’ve just rebooted my machine, sometimes I get to slide like 15 times before it crashes, but after that it’s every second or third slide.

Here’s super weird part! In screenshot above, you can see I added a Print node between Update and Set Capsule Half Height, as part of my trying to figure this out. I did this on other timeline too. Thing is, with print nodes there, it never crashes. Something about having to go through that node before it gets to Set Capsule Height stops it from crashing, I guess. I’ve slid without crashing like a bazillion times now, but second time I slide after removing nodes, crash.

As a workaround for my actual problem I can just print blank, but I’d be super interested to hear anybody’s thoughts on why this is happening.

Hi ,

I’ve assigned someone on our team to look into this for you, and if they have questions for you they’ll post them here.

It may be helpful to get crash dialogue and log from your project after this crash occurs. Next time you reproduce crash, please copy information in Crash Reporter and paste it here. Then find log for project and /attach it here. You can find log in your project’s Saved\Logs folder.


Hi ,

Also, what values are you using for Capsule Half Height and Capsule Radius. I’ve been tracking another crash that could be related to these values.

Hey guys, sorry, didn’t see this.

capsule half height was trying to lerp from 96 down to 32, then 32 back up to 96. No instances of overlap on those timelines or anything, it was always those values. Initially I was also lerping Capsule Radius, but realised I didn’t need to and deleted that part. Crash persisted, so radius part was seemingly uninvolved.

I forgot to attach log and can’t get one right now, but did check it out at time. I had no unexpected messages at all - log just cut off halfway through a line every time.

I’m still unable to reproduce this in-house. Once you have time could you also try to supply a small test project with crash?

Hey ,

Have you had time for additional info or to create a small test project for this?

Hey TJ. I’ve migrated char into an empty project to test but so far haven’t been able to get crash to happen there. It is weird. I’ll keep smashing my face against it and let you know.

Hey ,

Any luck on this one?

Hi ,

We haven’t heard back from you in a few days, so we are marking this post as resolved for tracking purposes. If you’re able to reproduce this in a new project, please post back here with an update to reopen this report.