Hey Daniel,
Thanks for reporting this crash. I’ve reproduced the crash and entered it as [UE-35602][1].
I do have a “workaround”, which is actually the way you should do this, even if this crash is resolved. Instead of casting from the AnimGraph, which only has a bool as to whether it’s a valid cast and doesn’t have an isValid? check, you cast from the event graph and define the Mesh Component as a variable. See Below:
Event Graph
Anim Graph
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Hi,
I was away for a couple of weeks so wasn’t able to try out your workaround. Unfortunately the instructions posted above are still giving me array out of bounds crashes (this is now on 4.13 as I upgraded the project before tackling the slaveAnimBPs again).
If I try setting all my slave-meshes together to use my slave animBP, then the engine crashes with array out of bounds.
If I set them one at a time then I can compile/save by editing one at a time.
If I then try launching the game after setting them one at a time, then the meshes using the SlaveAnimBP have dissapeared (the meshes aren’t attached to the body anymore or have been deleted - not sure which) and after a few seconds the engine crashes.
Once I reload my project, I can open my character blueprint (couldn’t in 4.12 as it would just crash and I’d have to delete the slaveanimBP uasset file), however if I click the viewport tab within my character blueprint the engine crashes again with the array out of bounds error in the logs:
[2016.09.19-14.13.17:697][766]LogWindows:Error: Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\Build++UE4+Release-4.13+Compile\Sync\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 833]
[2016.09.19-14.13.17:697][766]LogWindows:Error: Array index out of bounds: 0 from an array of size 0
At least since the characterBP in 4.13 does open after a crash to the event graph I have the opportunity to clear the AnimBPs from the slave meshes so I can save/compile to make the project usable again.
Any other suggestions on a solution to the crashes would be appreciated.
Thanks.
So you set up the Slave AnimBP exactly like in my screenshots? Using the isValid check in the event graph?
I’m trying to look up your crash in our system, but can’t find any crashes for the EpicID linked to your account. Are you sending the Crash Reports?
Can you PM me a link to download your project? I’d like to see this for myself.
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Hi,
I realise you’ll have been busy with other things but I just wondered if you’d had a chance to look at the project I PMed you the download link for, to see if anything leapt out over the crashes.
I’ve had another go sending a crash report so if you’d like to check my account and see if any exist now or not then at least I’ll know if they are getting through.
Thanks.
Hey Daniel,
Apologies for the delay. I think the email notifications for your PMs got lost in the mix. I’m taking a look now.
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I looked up your crash and reproduced it myself. It is the same callstack and source context for UE-35602 that I listed earlier. Thanks for confirming it.
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Thanks for getting back to me and letting me have an update.
It’s a shame your work around didn’t work for me but I don’t mind waiting on 4.14.
Was this ever fixed or does setting master pose component still bust the engine’s collision code?
Sadly the issue still exists 
Hi all,
This was tested and resolved in 4.14. Your issue may be unrelated to the original issue here. Can you please post a new thread with details about your setup so that we can investigate it?
Correction: The Issue was marked as won’t fix, but there is a workaround listed below. We are moving away from Master Pose and towards Copy Pose. So the workaround is actually the recommended method.
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