AActor::bIsEditorOnlyActor with Game View enabled behaves inconsistently for Nanite and non-Nanite static meshes

Development Rendering
, ,
1

In editor, when Game View is toggled, the visibility of actors with AActor::bIsEditorOnlyActor set to true is toggled. This works correctly for non-Nanite static mesh actors but does not work for Nanite static mesh actors.

For non-Nanite static mesh actors, this is handled by this code in `FPrimitiveSceneProxy::IsShown`:

if (View->Family->EngineShowFlags.Game)
{
	if (DrawInAnyEditMode)
	{
		return false;
	}
}

The equivalent code does not seem to exist for Nanite static meshes though.

Thanks!

2

Steps to Reproduce

  1. Open a new empty map
  2. Add a nanite static mesh actor to the map
  3. Add a non-nanite static mesh actor to the map
  4. Enable “Is Editor Only Actor” on both actors
  5. Toggle Game View on/off (press G)

Observe that the visibility of the non-Nanite static mesh actor is toggled, while the Nanite static mesh actor remains visible.

3

Hello,

Unfortunately this issue has existed since 5.4 but hasn’t been prioritized yet. I’ve updated the issue so it will be visible publicly soon: https://issues.unrealengine.com/issue/UE-210913

The note on the internal issue suggests this can be fixed with the following code change (untested)

// in FPrimitiveSceneProxy::FPrimitiveSceneProxy
 
DrawInGame &= !InProxyDesc.IsHidden();  
// change to
DrawInGame &= !InProxyDesc.IsHidden() && !InProxyDesc.bIsOwnerEditorOnly;
4

Thanks Alex! We evaluated that change but ultimately decided against it for now. We’ll keep an eye on the bug for now, thanks again.