World Composition - Performance problem with multiple levels

gestoryscht
Tue, 25 Sep 2018 14:15:23 +0000
World Creation

Helly guys,

recently I tried to use the world composition feature of Unreal, but I have massive problems with the performance and I can’t find any solution for this. Here are some details:

I want to create a 18x18km landscape and for this I am using world machine. The terrain is created, everything is fine and now I exported the whole map in 18x18 Tiles. Each tile is 1009x1009px and I press the import button in UE4.
The world composition is builded and my performace is extremly bad - around 5fps.

Well okay I thought, these many tiles are way to much, so I have to reduce them. Exporting the same terrain now with 2017px tiles, to have 9x9 tiles. The same - the performance is a bit better, but still around 15fps. Okay, next round - now with 4033x4033. The same. Now with 8129x8129. The same.

The best performance I have got so far, was around 50fps in the close up, but this is ridiculous low - especially with the PC I have here (2x Xeon E5-2680 + 96GB RAM + GTX 1080 Ti). The strange thing about this is, that unreal doesn’t use the full potential of the PC. 2-3% CPU and around 20% of the GPU - so there have to be something else wrong.

My ratio so far was 1m/1pixel - so I tried 10m/pixel. The same result.
Whenever I add a map to the world composition and place a landscape, the fps drops immediatly from 120+ to around 50. This can’t be right.

What is my problem here? Am I using the wrong math formular for the textures, or is something else completly wrong?

Just to get it right, this is my current approch. I don’t need exact values, so I useed the values given by epic.

docs.unrealengine.com

Landscape Technical Guide

Technical Settings for Landscape.

1009 pixel are around 1 kilometer.
For 18 km, I need a Normal Build resolution by 18162px (+1).
My tile settings are at a resolution by 1009px and a tiles per side of 18x18.

When I want to have a 10m/1px ratio I divide the whole thing with 10 and afterwards in Unreal I use a scale of 1000
Just for example.

I hope you can help me and have a great day - thanks!

EDIT: Oh, one thing to mention.
I can’t use streaming distance, because there will be situations where I see the whole scenery. So this is no option, but I think this isn’t the problem here. Even with one single level the drop happens.

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