(post deleted by author)
Hello, we are still experiencing this issue. @Tina_Wisdom
Upgrading a 5.5.4 project to 5.6.1 causes meshes imported (possibly only via Datasmith for C4D) to swap or destroy material slots when upgrading.
You can see here, this lid, when upgrading to 5.6.1, the material for the painted wood is missing and is replaced by the metal which existed in the other slot.
However, if we disable Nanite on this mesh, we see that the original material slot is now broken:
We have also tried disabling Nanite in 5.5.4 before project upgrade, and then upgrading to 5.6.1 without any Nanite static meshes. This creates an alternative scenario where the non-Nanite mesh is fine, and displays correctly:
But when enabling Nanite on that mesh, the issue returns:
We’re really not sure what to do here, as there doesn’t seem to be any other pathway from 5.5.4 to 5.6.1 without a simple project upgrade, and this is happening from the upgrade itself without any other changes made to the project.
This is a blocker for us, because we’re unable to move to 5.6.1 without this issue happening, meaning that our art assets are stuck in 5.5.4. It would be an enormous job to reimport all assets fresh in 5.6.1.
Another update to this, it seems that meshes that once had two “mesh sections” in the static mesh editor, now have three:
And when enabling Nanite on this mesh, it returns to two materials, but for some reason takes the duplicate section instead of the original second section
I haven’t found a way to remove the extra section in the non-nanite mesh yet, but I suppose if there was a way to delete the spare section, it might preserve the original material slot order when turning Nanite on?
Section 0 (the newly added/false section) contains nothing:
Section 1 (the original metal material slot) contains the expected area:
As does Section 2, showing the painted wood material:
So for some reason, an excess Section 0 is being added between 5.5.4 and 5.6, and when Nanite is enabled, that Section 0 is removed (because it has no mesh data assigned to it) but it breaks Section 2’s material slot as a result.
I’ll keep trying things.
yeah I think I reported the issues a few times because I wanted to invest in using this feature, and did. I hit a wall with this amount of breakge / bugs. Which they warn you about but it still sucks a donkey.
My theory is that they are trying to roll it into the new features of the 2D animation tools, so it can do 2d and 3d since they have some things in common. So it will be broken for at least another year.
I’d have to agree, this is a massive problem when trying to create builds right now. Even worse is that what it’s complaining about doesn’t even show which struct is causing the problem here 
. What’s even wilder here, is it would package maybe 1 out of 10 times. I don’t understand.
The main issue I’m getting at least with 5.6 is UK2Node_FunctionEntry::Serialize() with blueprints. For the most part, it jumps from different blueprint asset to different blueprint asset that it fails on. It can package maybe 1 out of 10 times though… that being said, it’s issue is always inconsistent UATHelper: Packaging (Windows): LogCore: Warning: ‘UStruct::IsChildOf’ was called with a null ‘this’ pointer - this is no longer supported.
PackagingResults: Warning: ‘UStruct::IsChildOf’ was called with a null ‘this’ pointer - this is no longer supported. UE 5.6.1 is a bit broken at this moment due to this…
Hello, Reporting that Groom Bindings that were working in 5.4.x till 5.5.x are now crashing the editor when loaded.
Tried using old assets and importing new ones as well with the same outcome.
I can Import grooms fine, I can create groom bindings as well on static meshes, but as soon as I apply a groom binding to a animated geometry cache the editor crashes.
I suspect Its got something to do with how the importer got updated with this attribute parametter but I cant find documentation how to properly use this to test if that is the issue.
Thank you for mentioning/reporting that issue. Would it be possible for you to share a repro project for this so that we can investigate the issue? Thank you!
/Charles.