Unreal Engine Issues
Unreal Engine Issues
LayeredBlendPerBone without BlendRootMotionBasedOnRootBone exaggerates root motion
UE - Runtime - Animation - May 27, 2023When BlendRootMotionBasedOnRootBone is false, the LayeredBlendPerBone is aggregating root motion of the child poses ontop of the base pose root motion. (ie. if the first child pose's blend weight i ...
Niagara Mesh Renderer registers NumParticles x NumMeshVariants TLAS instances
UE - Rendering - Graphics Features - Ray Tracing - May 28, 2026When using the Niagara Mesh Renderer with multiple mesh variants selected via MeshIndex, the number of TLAS instances allocated is NumParticles × NumMeshVariants and enabling the Path Tracer can ca ...
Client Gameplay Effect stuck on due to duplicate ReplicationIDs
UE - Gameplay - Gameplay Ability System - Oct 31, 2025We've been tracking down a problem recently with the Gameplay Ability System where a gameplay effect is properly removed on the server, but the client has the gameplay effect stuck on permanently. ...
FGameplayTagCountContainer::Reset() leaves explicit tag state and causes counts to accumulate
UE - Gameplay - Gameplay Tags - Aug 4, 2026[Summary] In UE 5.7 and later, if a tag is added once to an FGameplayTagCountContainer, the container is reset, and the same tag is added once more, GetExplicitTagCount() returns 2 instead of the e ...
[AI] Gaps between Nav Mesh tiles in World Partition map causing movement issues
UE - Runtime - Character - Nov 4, 2025Navmesh has seams between some tiles that are actual edges rather than previously found "gaps" where it was a debug rendering issue. Pathfinding does fail between these tiles to go straight across. ...
Mover Plugin: UNavMoverComponent::GetFeetLocationBased() returns incorrect FBasedPosition when using WalkingMode over a Movable floor, making UPathFollowingComponent erroneously detect a blocked move
UE - Gameplay - Player Movement - Mover - Nov 12, 2025Function UNavMoverComponent::GetFeetLocationBased() on file "NavMoverComponent.cpp" returns an FBasedPosition built from an FRelativeBaseInfo. The "MovementBaseInfo" is read from key "CommonBlackboa ...
Internal Compile error received from rearranging Format Text nodes
UE - Gameplay - Blueprint - Dec 18, 2014Internal Compile error received from rearranging Format Text nodes Output Log of Error: LogBlueprint:Error: [compiler] Error Internal compiler error inside CreateExecutionSchedule (site 2); please ...
In some situations, a Blueprint can become devoid of an Event Graph. While no graphs are present, multiple variables can be created with the same name.
UE - Framework - Blueprint Editor - Aug 26, 2024In some situations, a Blueprint can become devoid of an Event Graph, or be created without one from the start. For example, function "FKismetEditorUtilities::CreateBlueprint()" in UE 5.4 does not ca ...
Hot reload causes placed actor to lose variable references
UE - Foundation - Cpp Tools - Hot Reload - Nov 9, 2017Preforming a hot reload causes placed actors to lose code based variable settings. More repro steps: 1. Open UE4Editor.exe 2. Create a First Person Code project 3. Build the project for Developme ...
Data Asset Instances created from Blueprints and are not selectable in asset pickers until their parent Blueprint is loaded. They are also not displayed correctly in the Content Browser
UE - Framework - Blueprint - Sep 3, 2024Consider a C++/BP class containing an EditAnywhere/InstanceEditable variable with type (UDataAsset*), (UPrimaryDataAsset*), or any of their subclasses. When setting this variable using a Property Ed ...