I’ve been having a lot of difficulties with the asset importing pipeline, so to try to help make the editor more solid I’ve put together some repro steps, along with a description of the biggest issues I’ve run into.
Repro instructions created with: UE4 4.9.1 / Linux
- Create a new UE project
- Drop the attached .blend and .fbx files into subdirectory of Content
- Import the attached Test-LOD0.fbx file, selecting these options:
Import Uniform Scale: 0.01 +
Uncheck Import Materials/Textures (I think unselecting import mats doesn’t matter, but it’s what I did).
- Drag the resulting static mesh into your scene. You should have a (2m)^3 cube. Note in the details for the static mesh actor that it has a single material slot.
- Right click it in the content browser and select “Import LOD/LOD1”, and select the Test-LOD1.fbx file. It’s actually the very same .fbx file as LOD0. Both have a single material named MI_Material0_skin00
The bugs I encounter in 4.9.1:
BUG 1 -->> Note that in the details panel for the Test-LOD0 static mesh actor, the “Materials” section now has two entries. I think there should be only one: it’s the same material with the same name in both.
If you want to argue this is intended, I have a stronger argument in my pocket to use :P. Go back to “Import LOD” and RE-import the same Test-LOD1 object over LOD 1 again. Now there are THREE materials slots, where there’s really no possible case that the two LODs have 3 materials between them. I can get as many there as I want - a dozen, if I keep re-importing the LOD.
BUG 2 -->> Double click the static mesh to open it and view the details panel. Note that viewing “Base LOD” looks fine, where if you toggle the view to “LOD 1” with the drop down, the object disappears. Yet it was the same object we imported to LOD1.
I believe this is because the LOD-level import does not abide the “Import Uniform Scale” parameter. If in the details panel for the mesh, you change the “Build Settings / Build Scale” for LOD1 to be 0.01/0.01/0.01, save, and exit the SM editor, it’ll ask you “Would you like to apply the level of detail changes to Test-LOD0?” Select “Yes”. Often the editor crashes for me at this point, but if you get through that, re-open the SM again, and LOD1 now has the right scale and looks the same as LOD0. It loses the scale every time you re-import it though, whereas LOD0 preserves the import settings each time you re-import.
I’ve also, randomly, seen LOD1 be rotated 90deg with respect to LOD0 for unknown reasons.
BUG 3 -->> Doing much asset importing makes the editor very crash-prone. It’s mostly stable for me outside asset importing, but if you re-import these objects a number of times, opening up the SM editor each time, it doesn’t take too long before it crashes. Potentially this is a Linux-specific bug, though I haven’t tried it on Windows to see. It’s random, so hard to give an exact repro case, but it’s usually within 5 or 10 minutes of importing things for me.
Possible Bug 4 → Somewhere, and I can’t find it just now, there’s a setting to auto-import the .fbx files when they change on disk. This isn’t enabled in this project as i can’t find it. However, in my main project, this works OK for LOD0, but LOD1+ don’t work, and I have to re-import them by hand each time I change them. This is a more minor issue, but I do have to remember to keep doing it.
Attached is a Test.zip file with the .blend and .fbx files.
Hope this helps! BTW even though I’ve run into bugs, I appreciate all that this is doing for me behind the scenes. It’s a very complex thing, no doubt. There’s a lot of good stuff happening.