Landscape heightmap import duplicates single tile in World Partition (UE 5.7+)

Summary

Importing a heightmap into a World Partition level produces an incorrect landscape where a single tile is repeated 16×16 times instead of displaying the full terrain.

This bug affects versions 5.7.0, 5.7.4, and 5.8.0. Versions 5.5.4 and 5.6.1 work correctly with the exact same files and the exact same import settings.

What Type of Bug are you experiencing?

World Creation Tools

Steps to Reproduce

Create a new World Partition level in UE 5.7+

Open Landscape mode

Click Import from File

Select a 16-bit PNG heightmap with a resolution of 8129×8129

Use the following settings:

    Location: 0, 0, 0

    Scale: 36.88, 36.88, 234.375

    Flip Y Axis: disabled

Click Import

Expected Result

The terrain should appear with the correct heightmap geometry, covering an area of 3 km × 3 km.

Observed Result

The terrain displays a single portion of the heightmap repeated 16 times in a mosaic pattern (4×4 or 16×16 depending on the case). In Wireframe view, the geometry appears correct, but the final rendering shows the repetition.

Affects Versions

5.8
5.7

Platform(s)

Windows

For crash reports, include your callstack

No crash

Additional Notes

Current Workaround

Create a Basic level (non World Partition)

Import the heightmap normally

Convert the level to World Partition after import

This method works but is not viable for projects requiring the progressive addition of many terrain blocks.

Technical Information

Element Detail
Heightmap source Houdini 21.0.440 (16-bit PNG export)
Resolution 8129 × 8129 pixels
Format 16-bit grayscale PNG
Scale 36.88, 36.88, 234.375
Affected versions 5.7.0, 5.7.4, 5.8.0
Working versions 5.5.4, 5.6.1
Level type World Partition only

Impact

This bug prevents direct heightmap import into World Partition levels in recent versions of Unreal Engine. It affects large-scale terrain creation workflows, particularly for projects using LIDAR data or external heightmaps.