Foliage hurting fps

[Nino_Mancuso]

Hi UE hivemind, please help:

I’m using the Foliage tool to place some quixel assets on a map and its absolutely crushing my fps.

so I’ve got the static mesh foliage instances in the menu, I brush them in, they seem fine. Dead Broom Brush asset from Quixel. Not super extravagant, though LOD 0 has 290 vertices.

I have a chair in for reference, just paint a number of them in.

And cover a large area (chair really small on right). I get a few thousand down.

All good, fps fine. I zoom around, preview in game mode, not bad.

So I add another static mesh foliage to add variety. It’s similar but with only 50 or so vertices in Lod0

I paint the same area, things start really dragging. I cover the same general area with grass, again, this is pretty sparse compared to what I’ve seen in some maps, and I’m running on a rented 10900X with an RTX 2080Ti now, fps is 120 usually in editor, and 100+in game, however fps drops to 50-60fps in game whenever I get anywhere close to grouped foliage.

I haven’t even covered the map with anything else at this point. Am I going about this incorrectly or missing some part in the setup?
I’ve seen other projects on tutorials overflowing and brimming with flush, waving verdant growth and I’m getting absolutely pummeled on spreading some dead plant around.

currently I’m using:
Static Mesh Foliage instancing,
No shadows on the foliage, direct or static,
culls not too far away.

[ClockworkOcean]

I can’t tell you anything very exciting I’m afraid.

Foliage is always a total juggling act. Obvious areas to look at are:

1. LODs and textures of the meshes.

2. Cull distance

3. Shadows of the directional light ( I’m assuming it’s moveable )

4. Density of the foliage

One thing I would say is, try it with some simple grass assets, there are plenty of free ones on the market. Quixel assets are no compromise in all respects, probably has a lot to do with it.

Also, if you ever get a copy of any well written landscape / foliage solution from the market, you’ll notice that about 60 fps is considered acceptable. You’ll be hard pushed to get above that with any decent amount of coverage.

[Nino_Mancuso]

Thanks for the quick reply.
I wonder if Quixel’s master foliage Material could be an issue? It does utilize Translucency I notice …

Just ran a quick test with a Foliage mesh and Foliage Material from the “Mastering Materials” tutorial. I notice I can throw that foliage all over the map and have absolutely no issue…

No translucency used in this one.

I’m just grasping with what little I know at the moment, but maybe that’s creating the issue. I’ll have to look at some of the Visualizers tomorrow. Maybe I can reintegrate the quixel billboard and atlas textures with a different Master Foliage Material to better effect.

I noticed that you’re right there are a lot of grass foliage options on the marketplace, not a lot for arid climates however!

[ClockworkOcean]

Ah, there you go, complex shader. That Quixel stuff isn’t generally game ready…

[Nino_Mancuso]

The lightmass density was also not optimized for the quixel meshes, it was set to 64 and was not happy in the visualizer. Dropped most of them to 32 and 16 and much improved.

[Nino_Mancuso]

The lesson here is to make sure one checks one’s lightmass density settings.

[ClockworkOcean]

Or could the lesson be: Don’t assume you can use Quixel assets in a game context…

[Nino_Mancuso]

very true! Though I’m not making a game, just a large environment for virtual production. I need the background panning outside a vehicle window for an LED wall. Still, for little details like that it should still be optimized

[ClockworkOcean]

Ok, so the grass is just whizzing by? You could use almost any asset!

[Nino_Mancuso]

In theory yes, until we get in there and realize it looks horrendous when and if the car stops!
Better to approximate.
But bushes are soon to be the least of my worries as I delve into nDisplay…

[ClockworkOcean]

Rather you than me…