Dear Epic Support,
our game shows meshes with wrong scale and rotation, randomly. This issue does not happen consistently, and we don’t know how to debug it. What we believe it could be happening is that some instance buffer get corrupted, because they all look like foliage.
It happened in editor, and in cooked build, and when we turned off nanite via console command, when it happened, the issue disappeared. When they happen, they stay there until we don’t restart the level.
It happens more frequently on low-spec hw, but it’s not consistent. We are speaking of PC only, Windows 11
I’d like to know if it rings a bell to you, or you have any hints. We already eliminated the “invalid foliage” instances, but it seems there’s more that could be invalid.
We place the foliage either with PCG (freezing the result, not runtime), with Landscape grass, and with foliage.
We’d love to pix it, but since it’s random we can’t attach pix after it happens.
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Hey Emanuele,
That looks like vertex corruption indeed, but I have not seen this issue in some time since we have done more work on Nanite foliage after 5.6. Are you seeing this issue on a development or testing build? Then you can use the DumpGPU utility to retrieve the contents of the Nanite Streaming Pool and write the raw byte buffer to disk. You would need to set the following cvars either in a config or once you encounter the corruption:
r.DumpGPU.Texture 0
r.DumpGPU.Buffer 2
r.DumpGPU.Test.PrettifyResourceFileNames 1
Then you can run **DumpGPU -unified_filter="*[Content removed] you will only get the committed data when the dump is triggered.
Feel free to let me know if that helps or if you need some more clarification.
Cheers,
Tim
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You are welcome. Glad to hear you already found a fix. I will mark it as the best answer and resolve the ticket. Feel free to let me know if you have any more questions.
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Thanks Tim, in the end we identified the mesh and solved the issue.
For the records, we fixed it by re-registering the Instanced Static Mesh Components of those meshes, when the CVAR foliage.densityscale changed.
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