Unreal Engine Issues
Unreal Engine Issues
Landscape raytracing geometry always updates every frame
UE - Graphics Features - Ray Tracing - Apr 11, 2025LOD 0 Landscape meshes are always updated in FLandscapeComponentSceneProxy::GetDynamicRayTracingInstances because* r.RayTracing.Geometry.Landscape.LODsUpdateEveryFrame* (GLandscapeRayTracingGeometry ...
Changing WITH_SUPSTEPPING prevents 4.10 from compiling
UE - Simulation - Physics - Nov 24, 2015In the file EngineDefines.h, changing 37 to read "#define WITH_SUBSTEPPING 0" will cause the solution to fail the build process. ...
Blueprint Launches onto tvOS fail during runstep: Error_DeviceOSNewerThanSDK
UE - Platform - Mobile - Apr 19, 2019When a user launches blueprint project to a tvOS device they will fail to run the project during the run step and if they manually try to launch the app from the dashboard. This issue does not repr ...
Crash in Vulkan when changing Source Texture for Rect Light
UE - Rendering Architecture - RHI - Jan 5, 2023Regression: Tested in UE5/Release-5.0, no crash occurs so this is a regression No crash occurs in 5.0, but the rect light's light does not change based on the Source Texture. Rect lights function a ...
Pawn Blueprint cannot have variables default value set in Engine ini
UE - Gameplay - Blueprint - Jun 1, 2017When using a pawn blueprint, you cannot modify the value of a variable in the config files. This issue does not affect other kinds of blueprints, as this issue does not affect actor blueprints. Re ...
Animation Sharing Plugin Removes Mesh Collision
OLD - Anim - Jun 11, 2019The referenced documentation does not state anywhere about collision being affected by animation sharing nor is the user expecting it to be affected. Even when the Collision Preset is overridden to ...
[CrashReport] CastChecked<UAnimBlueprint,UBlueprint>()
OLD - Anim - Jul 14, 2017This is a common crash affecting users in 4.16. Users have not provided additional information. Source context not available ...
Low-level memory tracking has negative values for "FMallocUnused" and "Untracked"
UE - Foundation - Core - Oct 6, 2020"FMallocUnused" is immediately bellow 0. "Untracked" is reported to go below 0 after very long playtimes (over 36 hours). Reported in version 4.25.3(CL 13942748). Tested and found negative values f ...
Reimporting an asset during PIE overwrites the bAllowCPUAccess value to true
UE - Editor - Content Pipeline - Import and Export - May 22, 2025When reimporting a static mesh asset before PIE execution, the value of bAllowCPUAccess is false. If reimporting a static mesh asset while PIE is running, the value of bAllowCPUAccess is true. In a ...
Missing UV Clamping or Clear in SunAlphaPS_Mobile
UE - Platform - Mobile - Nov 13, 2025In: void SunAlphaPS_Mobile( float2 InUVs[8] : TEXCOORD0, in FStereoPSInput StereoInput, out HALF_TYPE OutColor : SV_Target0 ) { OutColor = SunUnBias(SunShaftAndDofTexture.Sample(SunShaftAndDo ...