We are in the process of migrating an older (4.21) project into Unreal 5.5. This is NOT “new” data, this is legacy data that was fully built in Unreal4.
After reviewing the data in 5.5, we are seeing some strange Material UI issues on certain materials… specifically, we’re seeing cases where Scalar Parameters are showing up on the UI of child/instances as also having a Texture Sampler slot?
There appears to be a duplicate parameter with the actual scalar data, but the presence of that texture picker at all is worrisome.
Here’s a visual aid:
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Steps to Reproduce
Simply open the provided Project Content in a 5.5 version of Unreal. (zipped Content folder provided with post).
Once open, note the two materials located at:
Content/Material_UI_Issue
One is a Parent Material, the other is a Child/Instance of that parent (each named clearly). Observe the strange UI behavior on the Instance, specifically that some Scalar params are showing up as Texture params.
Hello,
I had a chance to run this by the team that looks at Materials and relevant subsystems and they believe that this issue arises from the deserialization mismatches due to large difference in the engine versions. Further, they suggested that first migrating to 4.27(last UE4 version) and then migrating to UE5 might mitigate the issues. While this would be painful to migrate in steps, it will definitely help debugging the issue better.
If you get a chance to give it a try, and are still facing issues, please let me know.
Regards,
Vedang