just updated to 5.4 and now I´m geting crashs with a blueprint I´ve been working on for a while.
Its rather complex with 300plus skeletal meshes (modular human anatomy model) and I don´t really know what I´m doing with blueprints.
I´ve seen a few other posts with the issue and unfortunately I don´t have the time right now to do all the steps for a proper bug report, but I´d thought I´d report it anyways.
Ok, so I´ve troubleshooted this some more and was able to find a workaround for now.
I had to disable “support hardware raytracing” and then I could uncheck “Use compute skin cache”, which solved the crashes for me.
Not happy with this, so if anyone finds a better solution or this IS a bug, I´d be happy to hear!
I’m getting this one too… Happens everytime I open a dropdown menu for a Skeletal Mesh variable.
Edit: I have my project on the D: drive, but Unreal is installed on C:… Maybe that’s the issue? I’m not really in a spot where I’d like to change that setup right now.
Version 5.4.1 encountered the same issue (which occurred in the packaged test game), and I attempted to resolve it using the first response method. I hope the engine can solve this bug.
AFAIK the D: letter reference can be ignored. Its something that has to do with the developers only and doesn´t actually reference anything on YOUR D: Drive.
Seen it popup in multiple places where it doesn´t mark an error or crash.
Just a few more hints that may help troubleshooting:
I´ve also encountered another error in my master material that took me forever to solve.
I was using a custom triplanar function I purchased that used a few vertex interpolators and also a few “pre skin” local position and local normal inputs.
Those threw errors with nanite tesselation/displacement and I had to figure out a different approach to use with displacemend for the triplanar function.
Since that is also related to skin data, maybe there is a connection to the new nanite tesselation in Unreal.
Another thing to note:
Nanite tesselation also didn´t seem to work correctly for me with raytraced shadows, so I had to disable them anyways for my project.
Gave some blotchy shadow artefacts, similar to the known raytraced shadow artefacts with nanite meshes that could be fixed with that console variable (naniteraytracemode or something).
Just throwing this in here, but might be completely unrelated.
Nope. Either its bugged / a current restriction or its some combination of things in certain scenes.
Would help if everyone could try and list some things they have in their scene or project settings that might be related.
Like: Have you gotten raytracing enabled? Do you use displacement?
Any custom shaders on your metahuman?
Does it happen in a fresh project as well?
I’m fairly certain I didn’t have nanite or tessellation enabled at the time. I did try a blank project and didn’t get the problem. If I get time, I think I may just start another blank project and bring in my Skeletal meshes 1 at a time til the issue presents itself.
Update: Still happening in 5.4.2 (I was really hoping it would get fixed in a patch)
I also have such issue for 5.4 and 5.4.2 update and I fixed by disabling in your own project DefaultEngine.ini r.raytracing to false and if still crash change r.RayTracing.ForceAllRayTracingEffects=0
And it will work 100%
I am not sure why unreal should have such bug with an engine that it is used in all gaming industry, but the raytracing keeps unreal crashing so to the unreal developer please check that and try to fix to make the engine stable.
nobody else experience that problem?
I don´t see how its not a more common known issue, if NOONE was able to use raytracing with 5.4 anymore…
So its gotta be something more project specific.
I heavily edited our project settings over time, as we´re using a perforce setup where we constantly import from a master template, thats continuously evolving, so its tough for me to pin point what exactly might be only causing this issue for me…
Unfortunately I now have a project that requires raytracing (lots of translucent stuff), so its become a more urgent problem again…
Ok, I did some more testing.
Currently unable to create a new project, but I deleted all config files and just tested the skeletal meshes one by one without crash, they only crashed in my blueprint.
I then was able to pin point the issue to the lead pose component I use to control all skeletal mesh animations in that blueprint.
Was able to recreate the issue with a fresh blueprint actor AND a skeletal mesh using a different skeleton, so I´m pretty sure there is something wrong with that lead pose component node that doesn´t like GPU skin cache…
I wasn´t able to test in an empty/new 5.4 project at the time, but I tested in a 5.3 project and it didn´t crash there.
Very simple to recreate:
Create blueprint actor.
Add two skeletal meshes (name one leader, one follower)
In the constructionscript, add a “Set Leader pose component”.
Assign leader and follower.
Compile.
Hit “Play in editor”.
You should crash.
If anyone could confirm this happens not just for me/this project when using 5.4, I would really appreciate it!
I also have nested skeletal meshes and I am running into the crash when I turn on “Hardware Raytracing”, exact error you are showing as well.
I have the “Set Leader Pose Component” node on my construction script. As you can see in the screenshot below, I unlinked the nodes when I took the screenshot.
As soon as I connect that sequence into the nodes that flow into the “Set Leader Pose Component” and hit the Compile Button, I instantly get the crash.
So I think it might possibly have to do with the “Set Leader Pose Component” node like you suggested (not agreeing with GPUSkinCache).
NOTE: Everything works fine if I turn off Hardware Raytracing
If anybody has a workaround, please let us know. I need hardware RT so I can use GPULightMass and I cannot do it because it crashes out when I turn it on.
Not sure how to work around it either.
Problem is that if I don´t need raytracing in a scene, I could just leave the blueprint as is, if I could just define that per scene using the postprocess volume (and not using pathtracer).
But since its the GPU skincache and thats automatically enabled per project, it would still crash every scene containing that blueprint.
So, even if I would add a “lead component off” switch to the blueprint, I wouldn´t be able to use it WITH lead component in any scene, without getting the crash.
We´re only producing linear content and perforce, so in theory I COULD just branch the mainproject to a raytracing project where I have that lead pose component off, so I could at least render all shots that don´t need that, but that would also create a bunch of issues of having to keep track of project data…
Phew, happy to hear that you have all the same problems! I probably had a marathon compiling shaders & deleting caches I also use for one Blueprint the set leader pose and can confirm it’s crashing.
I still don´t get how thats not a major bug that would have been adressed in one of the first hotfixes.
It basically means anyone who uses any sort of customisable character (which is usually relying on lead pose component) would get these crashes with gpu skin cache/raytracing enabled.
Can´t be just the four of us, can it?
I went back today and made another attempt to track this down. My crash was happening when a drop-down menu was opened for any Skeletal Mesh or Geometry Collection variable. Here’s what I did:
Followed the previous advice in this thread and disabled Ray Tracing and GPU Compute Skin Cache
I was now able to open the drop down and noticed that along with my skeletal meshes were included a number of old Physx Destructible Meshes which are no longer supported by unreal
I deleted those Destructible Meshes from my project
Re-enabled Ray-Tracing and GPU Compute Skin Cahce
No more crashes!
So in my case, the crash was being caused by the existence of Destructible Meshes in the project. These have now been replaced with Geometry Collections. This explains why it wasn’t a common issue, since those started being phased out ages ago.
Also @Acolori_Medien I’ve been using Leader Pose Component all along without crashing since I have a meta-human on my player character… so I’m not sure if your crash may be coming from a different place, despite the error message in our crash logs being identical.
