Hi everyone,
I’m developing an editor tool that automatically deforms a landscape beneath a road spline using the Landscape Patch plugin.
I’ve spent several days debugging this and I’m now at the point where I’m unsure if I’m misunderstanding the intended workflow or if I’ve encountered an engine issue.
I’m hoping someone from Epic or anyone who has successfully used Texture Backed Render Target can point me in the right direction.
Intended Workflow
The workflow is:
Road Spline
↓
SceneCapture2D (Orthographic)
↓
Render Target
↓
LandscapeTexturePatch
(Texture Backed Render Target)
↓
Landscape Heightmap
The Scene Capture produces a grayscale height mask of the road which is then written into a Landscape Texture Patch.
Engine Versions Tested
- UE 5.6.1
- UE 5.8
The behaviour is essentially the same in both versions.
Landscape Patch Configuration
The patch is configured to use:
Height Source Mode
Texture Backed Render Target
Initialization follows the documented API order:
SetHeightSourceMode(TextureBackedRenderTarget)
SetResolution(…)
SetHeightRenderTargetFormat(…)
GetHeightRenderTarget()
SetHeightEncodingMode(…)
SetHeightEncodingSettings(…)
SetZeroHeightMeaning(…)
The returned render target is then updated using DrawMaterialToRenderTarget().
What Has Been Verified
The following parts of the pipeline are working correctly:
SceneCapture2D captures the road correctly.
Render Target contains the expected grayscale road.
Capture material outputs correctly.
Blueprint references are valid.
Landscape is correctly assigned.
Landscape Patch bounds are correctly positioned.
Patch receives the correct render target.
The captured texture itself looks exactly as expected.
Tests Performed
Test 1
External Render Target
Scene Capture
↓
External Render Target
↓
Landscape Patch
Result:
The Render Target is correct.
Landscape deformation is incorrect.
Test 2
Texture Backed Render Target
GetHeightRenderTarget()
↓
DrawMaterialToRenderTarget()
↓
Landscape Patch
Result:
Same behaviour.
Test 3
Migrated project from UE5.6 to UE5.8.
Initially suspected Blueprint migration corruption.
Rebuilt the capture Blueprint from scratch.
Result:
No change.
Test 4
Verified every stage independently.
- Capture
- Render Target
- Material
- Landscape assignment
- Patch bounds
Everything appears correct until the Landscape Patch attempts to apply the texture.
Observed Behaviour
Instead of applying the captured road shape, the Landscape Patch either:
- creates a large rectangular plateau
- partially updates
- or appears to ignore the captured height information
The Render Target itself is always correct.
The failure appears to occur during the Landscape Patch’s interpretation/application of the height texture.
Additional Observation
UE5.8 also appears to capture a slightly different area than UE5.6 using identical SceneCapture settings.
I’m not sure whether this is related or a separate issue.
Documentation Reviewed
I’ve worked through the Landscape Patch documentation and API, including:
- Texture Backed Render Target
- GetHeightRenderTarget()
- Height Encoding Mode
- Height Encoding Settings
- Zero Height Meaning
I also found bug UE-347682, although my issue appears different since the Render Target itself is correct.
Questions
- Has anyone successfully used Texture Backed Render Target with Landscape Texture Patch to deform a landscape?
- Does Epic have a sample project demonstrating this workflow?
- After writing to the Texture Backed Render Target, is there an additional step required to notify the Landscape Patch that its texture has changed?
- Is there anything obvious in the workflow above that I’m misunderstanding?
If someone from Epic has a working Blueprint or C++ example of LandscapeTexturePatch using Texture Backed Render Target, I’d really appreciate seeing it. I haven’t been able to find a complete example anywhere, despite searching the documentation and community resources.
