We have a long standing issue with random materials occasionally getting stuck with the default checkerboard material indefinitely. Only in editor, ever since we’ve upgraded from UE 5.0.3 to UE 5.3.2.
Slightly moving a node in the base material and hiting the apply button “fixes the issue”, although it adds a lot of frustraction and overhead to artists on our team.
This issue was described exactly in the second half of this closed UDN thread which was started about editor freezes on saving material instances. A now resolved issue that judging by the conversation seems related.
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Please look for these paragraphs written by a UDN member for the beginning of this context:
“We’ll give it a try. Please notice that we think that the freeze was a consequence, (not the cause) of not triggering some material compilations much before the issue occurs. We see the checker material in our maps and characters randomly with materials that do not have any issue, but simply the engine does not trigger the compilation and remains in that checker state forever. Only when a material instance affected by the checker issue was saved to disk, the freeze happened.”
…
“BUT, the issue with the materials which compilation is not triggered is still there. We still see random meshes and material previews with the checker texture in several parts of the editor: content browser thumbnails, main viewport (both editing and PIE), mesh editor, material editor, blueprint editor viewports, etc.”
I see this issue was created, although it incorrectly states that this issue is limited to material previews in the content browser:
Hello, I issue reported in https://issues.unrealengine.com/issue/UE-200553 still occurs in latest so I don’t think there are any fixes to cherry-pick, but I recommend you test your own repro case in latest if your material setup is different than the one in [the case you [Content removed] just to be sure.[Image Removed]
Hello, apologies for the delay. I’m not seeing any other known issues or fixes that might address this. Without a repro case or steps, we’ll need to collect more information, logs, and try to catch it when attached to a debugger to find out what’s going on.
Slightly moving a node in the base material and hiting the apply button “fixes the issue”
Does the issue happen in the base material or only material instances as mentioned in the referenced thread?
Thanks for trying, we have enough data to debug the issue described in UE-200553, but I don’t have an ETA for when it will be looked at. I have linked this post to our internal issue for the developer who ends up tackling this.
The issue happens randomly, with various different material setups, in all kinds of editor viewports. Unfortunately we don’t really have a solid repro.
I asked our tech artists this question, but as it usually is the case, as soon as you want to debug it, the issue doesn’t happen. I’ll post an update if we find out the answer to that question.
We have been trying to isolate a repro case without success as well. Our observed cases points to this having something to do with dependencies changing. E.g. a change to a material function used in the affected material. But no solid repro I’m afraid.
I think however, that the material preview issue described in UE-200553 is closely related, and that one has good repro steps. Would investigating that more closely be possible on Epic’s side?