ApexDestructibleActor Assert in DestructibleComponent.cpp

I have a destructible mesh that was fractured using the internal fracture tool rather than an imported mesh. It is being destroyed solely through blueprint functionality.

We are seeing this destructible actor assertion with quite a lot of regularity. (The specific line number is 1315.)

Assertion failed: ApexDestructibleActor [File:G:\windows-slave-1\windows-build\build\UnrealEngine4\Engine\Source\Runtime\Engine\Private\Components\DestructibleComponent.cpp] [Line: 1315]

I am attaching dump and log files.

Thanks,

link text

Hi ,

I’ll need more information to proceed here with this ticket.

I’ll need to know the following:

  • How have you got the DM setup that causes the crash?
  • Is this happening in a BP or just a DM placed in the level?
  • I see some information in the log about material instances, are you applying these to the DM? If so, is it at run time?

Any repro steps to recreate the issue in a blank project is very helpful.

If you have a sample project that can recreate in a new blank project, can you share that?

Unfortunately, without any repro steps on my end it’ll be hard to test and see if I can reproduce the issue to get it reported. This also helps in getting the ticket entered and fixed more quickly as well.

Any help you can provide is greatly appreciated.

Tim

Hey, Tim,

Thanks for jumping on this. Let me see if I can provide a bit more detail.

This is a DM that is only destroyed through a BP in the game level. We’ve tweaked it a lot to get a very slow breakup, rather than a quick explosion. (This is through repeated application of ApplyRadiusDamage events on the item.)

Settings for the block are attached in two images (would take a whole lot of different objects exported to get you the actual piece). We have NOT changed any of the Fracture Material Desc settings in the Fracture Settings, so they’re all defaults, but the material applied to the 2nd element in the materials settings on the skeletal mesh appears to be the one that is being used on the chunks. I’m assuming that this is happening in real time.

The crash happens at varying times as I break the block during play in editor (or in game). Sometimes it’s while I’m breaking the first one, and sometimes I have to break pieces off of more than one to get it to happen. (Sometimes it doesn’t happen at all.) It does become much more common as the cell site count increases on the DM.

Hi ,

I’m sorry for the delay. I’ve been investigating your issue but I’m not able to reproduce the crash. Could you also include your MachineID or EpicID from the crash report? Also, make sure to submit them.

Hey, TJ,

I just resubmitted the crash bug.

MachineId:73F3228E4F515FDB3D062987B8618D85

It seems to happen much more frequently if you line up a few of the destructibles and break them in succession, but that may just be a matter of probabilities.

Hmm, I’m still unable to reproduce this in-house and the crash is only happening to you. Could you migrate the asset to a new project to see if the crash still occurs? If it does, upload that project here or send me a link to download it in a private message over the Forums.

Hey, TJ,

I was trying to migrate the destructible actor into a separate project so I could upload, but the migration keeps insisting that it needs to migrate a whole lot of files into that project. I’m trying to figure out where the errant dependencies are so that I can migrate a more reasonable set of data, but we’ve been a little bit busy with our first playable.

I’ll get back on this next week. (Yes, we are still seeing the problem.)

Hi ,

I’m going to resolve this post for now. When you have time to continue troubleshooting this issue, just post back here to reopen the post.

Cheers,

TJ