Landscape Grass Output foliage floats when Landscape LOD Distribution is increased

Development World Creation
1

Hi everyone,

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I’m working in UE4.27 and using Landscape Grass Output to spawn grass, moss, and logs.

I’m seeing an issue where foliage appears to float slightly above the landscape, but only in certain areas. On flat terrain everything looks correct, but on slopes, ramps, and uneven terrain the foliage no longer sits flush with the ground.

What I’ve tested so far:

  • grass.FlushCache

  • RemoveLandscapeXYOffsets

  • Align to Surface ON/OFF

  • Landscape Resample

  • Landscape Smooth tool

  • Different Landscape Grass Types

  • Different meshes

Interesting findings:

  • After resampling the landscape, foliage is correctly aligned when Landscape LOD Distribution is set to 0.5.

  • Increasing Landscape LOD Distribution (1.5 - 2.0+) causes foliage to start floating again.

  • The issue affects grass, moss, and logs spawned through Landscape Grass Output.

  • Static meshes placed manually are not affected.

It seems like the foliage placement data and the visual landscape become slightly mismatched when more aggressive landscape LODs are used.

Has anyone experienced this in UE4.27?

Is there a way to keep higher landscape LOD distances for performance while preventing Landscape Grass Output foliage from floating above the terrain?

Thanks!