Assertion failed: IsValidCoord(InRenderCoord) ... Landscape\Public\LandscapeRender.h] [Line: 510]

[VeryClumsySloth]

I create a new project, landscape, build HLODs and nanites. When I press play in the edior it crashes. Does anyone know how to fix it?

LogWindows: Error: appError called: Assertion failed: IsValidCoord(InRenderCoord) [File:D:\build\++UE5\Sync\Engine\Source\Runtime\Landscape\Public\LandscapeRender.h] [Line: 510]

UE 5.3

[Doctor_Kannon]

I’m getting it too. The project will also package, but that level still produces the same error.

Try a smaller landscape size/res.

[VeryClumsySloth]

The size of my landscape is only 16 square km (about 7 miles?). I want to create map a bit bigger and would like to avoid wasting time on blending landscapes borders.

[Doctor_Kannon]

16km is ambitious right now. UE5 WP landscape has a long way to go.

Are you using landscape layers? Are they weighted and non-weighted? Try keeping them all the same (I’m using weighted-only now).

[VeryClumsySloth]

My main project is using UE5.1. I’m checking new features on 5.3. to decide if I should upgrade to new version, So this testing project in 5.3 uses only M_Ground_Moss from the starter content and nothing more, no layers.

I just created new landscape 1x1 km, it’s the same error. It just crashes after a while.

[Doctor_Kannon]

Beyond 10k, textures are your next issue.

[VeryClumsySloth]

Well I created another landscape 2x2, HLODs, no nanites and everything is good.

So now I either need to find the right settings for nanites or don’t used them at all.

[Doctor_Kannon]

Apparently nanites are problematic now too. I haven’t tried them on WP yet.

This post has a solution:

Nanite Landscape is Broken on 5.3? Cannot Save Project with Nanite on Landscape.

This is how you Generate Nanite LDS & Save. I just updated to 5.3 from 5.2 and there seems to be a bug where, when saving, it wants to generate Nanite for the entire Landscape prior to any saving, even if you only try to save a single Proxy at a time. So to correct for this, we want to load in only small sections of the LDS at a time. To do this: 1.) Turn Off Nanite for your Landscape & Save 2.) Select All Proxies and turn ON “Is Spatially Loaded” & Save 3.) Unload your entire level - in t…

[VeryClumsySloth]

Thank you, that solves the problem.

[quackcharge]

also running into this problem after turning off spatial loading for my proxies. turning it back on fixes the crash in editor.

The crash specifically happens when re-loading the level via a checkpoint debug menu. When only one proxy is non-spatially loaded, the crash does not happen but the game takes a lot longer to re-load the level

when launching the game via project launcher (shipping, by the book) the game does not crash when re-loading the level

[Doctor_Kannon]

My Landscape had Is Spatially Loaded set to false. The Proxies that I added (by gizmo stamp) had Is Spatially Loaded set to true. With these settings, PIE crashed the editor.

Setting the Proxies to false fixed the bug, PIE works.

Maybe the Landscape and Proxies should match?

But I can’t set the Landscape and Landscape Regions to true. I can check/uncheck the Proxies, but not the Landscape or the Regions.

EDIT: Resetting the Proxies to true also works… Very strange!

[SoloMode_Studio]

Hi, I was experiencing the same issue. I fixed adding this line:

FLandscapeRenderSystem::IsValidCoord | Unreal Engine 5.2 Documentation

above the 510 line.

Hope that helps.