Hello.
We have implemented a C++ pak mounting solution so that we can mount paks on game start but we are facing an issue where we are very limited to the packaged project’s batch concerning the mounting of PAKs.
We have assets and blueprints stored as a different module in /Plugins/ and made sure that they are all assigned specific chunk IDs up to their dependencies.
If we generate the PAK files from project A1 and mount them in the same project A1 through the generated executable they will be mounted correctly and assets will spawn and load as expected. But if we package the same project without the assets(removed from /Plugins/) which makes it project A2 and then try to mount the same paks previously packaged, some of them will cause a Fatal Error crash.
In other words it seems that we can’t load only some of the assets if they are not from the same packaging batch ONLY in this specific case where we use the packaged version that has not generated the assets. After debugging for a while I found out that some asset’s Animation Blueprint nodes were causing this crash and breaking the link was fixing it but as you might guess that’s not what we want.
To further test this I created an empty UE project B with a very simple asset inside of an empty Blueprint and generated a pak file that only contains the blueprint and its dependencies with the asset’s files. If I try to mount this pak in my packaged project A2 it will load the BP with the mesh but its textures will be missing and UE’s default grey texture/material is applied.
If I try to use a more complex asset that has animations sequences instead of ABPs I am back to the Fatal error crash when mounting it.
I am using the same Unreal Engine version 5.3.2 between each projects and I made sure that I am not having some missing dependencies from custom C++ code or plugins.
So to conclude I feel this is at least two different issues but I can’t find what to try to successfully mount paks that are alien to the initial project.
I saw that the missing texture was once a bug in UE 4.x.x but since it’s been more than 8 years ago I don’t know if that bug might have went back up in UE 5.
Any recommendations?
Best