4.14 LandscapeGrass Hierarchical Static Mesh Mobility Warning

While testing a project upgrade from 4.13 to 4.14, I get multiple warnings similar to -

Warning Mobility of Landscape_0 : HierarchicalInstancedStaticMeshComponent_0 has to be ‘Movable’ if you’d like to move.

Debugging against the launcher version of the engine, shows that landscape grass components are configured as -

HierarchicalInstancedStaticMeshComponent->Mobility = EComponentMobility::Static;

Yet the call to SetWorldTransform() on the component triggers a warning in CheckStaticMobilityAndWarn()

Hello Gavin1969,

Can you reproduce this in a new blank project and provide me steps so I can see this behavior on my end?

I am assuming from context you have added foliage to your scene, but seeing as how there are multiple ways to do this, I will need some clarification on the process you took in order to confirm what you are reporting.

Let me know if you have further questions or need additional assistance.

Thank you,

Hi Andrew
I’m very time limited, so if I do manage to do what you request, it could take up to a week.
That’s why, I took the few minutes to debug (as I stated) into the engine, which at least confirmed the ‘area’ of the issue.
It’s not the foliage system, it’s the LandscapeGrass system, as I indicated.
As such, we have no control over the mobility of the mesh that’s applied via the landscape grass system.
The HierarchicalInstancedStaticMeshComponent is created by the LandscapeGrass engine class, so is not user created.
My guess is that the engine would usually suppress this warning, but that somehow it’s be lost/dropped in this build.
I’ll reply if I get a chance to create a test case, but the process to implement will be exactly as documented for LandscapeGrass (not foliage), through the landscape material.
(If anyone else reading this has seen the same issue, it’d be great if they could ‘me too’ this).
Thanks
Gavin

This newly tracked issue seems related -