HLOD over the whole map

I have now seen several HLOD tutorials and tried out a bit. one question is always open to me. why create an HLOD volume? if I first activate HLOD under “World Settings” dann and then select HLODSetup under “HLODSetup Asset”. Then execute generate proxy mesh in the “HLOD Outliner”, Build and Save. doesn’t everything go automatically? the fps have never improved for me, I have 1011 actors. Always 40fps.

HLOD needs a volume/clusters because it will combine all meshes inside that volume and create a HLOD from it. And (as LOD/HLOD works) it will change the as you move away from the camera.
If you combine all meshes on your map, you are basically never triggering LOD/HLOD, since you are always “inside” the LOD all of the time (unless you move away from your map, it should trigger the HLOD)

But I do agree the documentation/Tutorials are a bit confusion and need lots of trial/error to get/understand everything.

You write “volume / clusters”, does that mean volume OR cluster?

  • I mean volumes! My bad.

A good workflow (that I personally use) :

  • Have HLOD Volumes in places that you would like to combine meshes for the HLOD;

  • Click Generate Clusters and see if they appear correct;

  • If everything is ok, click generate proxy meshes;


  • HLOD 0 to be left as default (will just combine meshes into 1, and 1 texture set) and toggle Only Generate For cluster volumes

  • HLOD 1 use as Simply mesh (so it will actually “decimate” your meshes, if you don’t toggle this, HLOD 0 and HLOD 1 will be the same

  • I personally add a HLOD2 with Simplify mesh with more decimated option (for super super far away!)

Hey, thanks for your very quick reply! That makes sense, but your answer has raised a new question for me.

You write “volume / clusters”, does that mean volume OR cluster?

If I open “HLOD Outliner” and click on “generate Clusters”, then clusters are created automatically.

If I then create levels 1 and 2 on the right in the LOD system.

Is the workflow already good? Then should I click generate proxy meshes?

Excuse my bad English. I also try a lot, but it always takes a long time when he creates the HLODs, so I ask here in the forum too.

Wow, thanks for so much input! Two questions have also come up.

You write:
“I personally add a HLOD2 with Simplify mesh with more decimated option (for super super far away!)”

What attitude do you mean by “more decimated option”?

And at the end a question where I haven’t got an answer yet, but I’m very curious.
Do you have experience with how much more FPS you can get out on average? (I know that’s hard to say because every level is different).

For the HLOD Settings:
When you have Simplify Mesh on, you can control how much it will decimate/reduce polys (Screen Size)
So for example, my HLOD1 has a Screen Size of 500, and my HLOD2 has a Screen Size of 150,
So in the end my HLOD0 have: 3320 polys, HLOD1: 2658polys HLOD2:1318 polys

Hmm it really depends. It will improve FPS, since HLOD is reducing drawcalls, both for static meshes and materials

Thanks again for your help :slight_smile:

Now I played around more and tried different things.

With slow PCs, it often helps not to build all proxies at once, but always 10 at a time.

I also managed to reduce the DrawCalls. But sometimes there are even a few more DrawCalls and especially a lot more Triangles drawn.

The reason for the triangles is that the HLOD Actors no longer work with the cull volume.

Is there maybe a trick?

If you would give me another tip, I would be very happy if you could tell me how you personally set the Desired Bound Radius at LOD 0-2.

My Desired Bound Radius in the example picture are:
L0 500
L1 1250
I have the feeling that too many actors are not marked at all.
My Landscape is 127 x 127