The Errors point to “DataSmithAreaLight” which is a Blueprint class inside the UE5.1 Installation folder, and I can see that if it doesn’t find a valid mesh, returns these errors.
By Default, “SetMobility Node” is not connected to the Branch Node, (see attached image) resulting in these errors, and either by converting the “Mesh Reference” to a “Validated GET Reference” or simply connecting “SetMobility Node” to the Branch Node, eliminates these null reference errors.
But the issue is we can’t pass this change to source control, as the class exists in the UE5.1 engine installation folder.
From the DataSmith folder, the “DataSmith Lights Scene” doesn’t have any Static Meshes, while the rest of the DataSmith Imported Scenes, suchs as “Details, Geometry” contain Static Mesh Arrays.
Therefore, this looks to be an engine bug, unless there’s a command to enter in the Config .ini files, which will force to ignore a DataSmith null mesh reference error?
I mean do we always expect every DataSmith scene to contain and return a mesh?
By connecting the previous “SetMobility” node to the Branch, the Mesh getter will be validated first, and not generate any errors at all, in case of a null…
Instead the previous “SetMobility” node is skipping the branch, and goes directly to the next “SetMobility” node.
That does sound like something was not connected properly so I logged a bug. Thank you for your report.
But I am confused because to reach to that point you need to have a light shape that is not in the DatasmithAreaLight datatable. The only enum value that is not there is “None”
and in both 4.27 and 5.1 if you put “None” in the light shape then you will get an empty mesh.
Where does this datasmith Area lights come from? Do you manually create them or they come from a Datasmith scene import? If the later could you share the file with us?
Thank you for replying back to this.
It comes from a DataSmith imported scene, where we also tried re-importing the scenes, just in case due to the migration from UE4 to UE5.1 something didn’t pass right, but still returns the same errors.
I will look into the possibility of sharing the scene, as it’s not my call to make, if it is ok, then sure no problem.
