LODs not working?

I am trying to auto-generate 2-3 lods for my Trees in my game which I am testing on 1 tree at the moment but when I select 3 lods then set the group to foliage or even anything else and click apply nothing happens and it only says lod0 even though i can see in the drop down that I can manually select them but they’re not listed above it except for lod0.

Is that a bug or does that mean my model is low enough that it should be okay? Any ideas?

Basically, I have what I think is a small open world map but originally I several non-overlapping trees to create a forest with about 40 of the tree presets fromt Tree & Plant Generator in the marketplace which looked nice and all along with several static meshes but the fps dropped to 22.

When I pulled out all of those trees I noticed it shot back up to 60. So now I am trying to make some improved trees and probably a lot less of them but i don’t want it to look weird either with not enough so it looks forest-like.

Update -

I think I may have figured it out but it’s just strange that I had to tick the custom box in the LOD Picker to enable them all to show up whereas the videos I watched in older versions of doing this just selected it and then they appeared so I thought it was a bug or something or maybe it changed, idk but at least i found a way to make it work now.

Sorry, still learning a lot on using UE4…

I’ve found that just clicking “Apply Changes” with an LOD number set is not good enough. You also have to set the decimation percentage, then apply. This must be done on each LOD.

Ahhh okay, thank you, i’ll give that a try. I was only doing the Number of LODs and clicking apply. I appreciate the help!!

No problem! Another thing you could try is to use the preset dropdown for “LOD Group.” This will set the number of LODs and their decimation percentages automatically. HighDetail is a good one, as it has 6 total LODs and each transition at fairly short distances.

I was also having an issue with foliage not switching to the next LOD until very far from the camera (you can see which LOD it’s using by looking at the 3D viewport Heads-up display). Even with using a LOD group, the way certain assets are built for some reason have too far of LOD distances. At this point, you can manually enter the LOD distances by unchecking “Auto Compute LOD Distances” and set the “Screen Size” for each. Something like 0.25 for LOD1, 0.1 for LOD2, and .04 for LOD3 should do it.

After further investigation, this appears to be a bug in the current versions of the engine. I was running version 4.15 and just upgraded to 4.20. The Auto LOD is not working. I am submitting a bug report for it, although the bug report form is down right now.

That’s what I was kinda thinking because I tried it again and same issue. Seems about right for a bug but I wasn’t sure if I was doing something wrong or not. I don’t remember if I reported it. I think I ran into the same issue with the bug report form being down but it was awhile ago so I don’t recall.

I found a way around it by setting it just as large or small asset but I don’t quite think its as optimized since the object I was originally trying to use it for is a bunch of trees I created for a game project.

Just got a response back from an Epic representative today about the bug. It is not a bug, but a UI update. To access all the individual LOD’s, you have to check “Custom” under “LOD Picker.” I believe the reason you’re not seeing your trees switch models is because the auto-computed screen sizes are way too low/too far away from the camera.

You can display each LOD with the drop-down menu: LOD Picker>LOD>LOD Auto. Change this to LOD1, LOD2, etc. to display each LOD. “Custom” must be unchecked in this case, but you can always check it later and it will keep your custom LOD settings.

I am glad to know the the LOD tool is alive and well! :slight_smile:

Ahhh… okay, that makes sense now. Thank you so much for the additional effort that’s very helpful and I really do appreciate it!!

It has just dead-stopped working in my entire level, on every mesh. I updated the LOD on a tree type, foliage, and now it won’t be affected at all by LOD. I can see every LOD, can try any preset, but it won’t actually do it when I place the mesh in the scene! I can edit LODs all I like, tick and untick custom… It was working a second ago and now it doesn’t work at all.

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