Unreal Engine Issues
Unreal Engine Issues
Float Curve evaluation may yield completely wrong results due to floating-point precision issue
UE - Anim - Runtime - Oct 31, 2024Note: This is possibly related to [Link Removed]. For some inputs, function UE::Curves::WeightedEvalForTwoKeys() inside file "CurveEvaluation.cpp" can incorrectly return the value of the first key, ...
Reference to control rig can be lost on actors with multiple skeletal mesh components
UE - Anim - Rigging - Control Rig - Apr 4, 2023In the attached project, when we initially add a control rig track for the actor with multiple skeletal mesh components, we add the control rig for the correct component because FControlRigParameter ...
Changing blueprint default values inside arrays only updates loaded child blueprints
UE - CoreTech - Jul 30, 2020The rules for delta serialization in UE4 are complicated, and the editor tries to hide them from you, which works 90% of the time but can lead to confusion and data loss in other situations. In the ...
Crash related to Vertex Painting - MeshPaint!CastChecked<AActor,UObject>()
Tools - May 23, 2016This crash was reported on the UDN. Upon further investigation it has been experienced by a handful of different users throughout 4.11 and 4.12. JIRA logged for tracking despite unknown repro steps ...
Cannot select child anim BPs for use in linked anim layers
UE - Anim - Runtime - Jul 15, 2021From UDN: [Link Removed] Unable to set a Child ABP with inherited interface to a Linked Animation Layer Instance Class. I have a ABP_Biped which is our main ABP. I have the locomotion (idle+straf ...
Instanced Static Meshes ignore max World Position Offset Displacement for bounds after UpdateInstanceTransform is called
UE - Graphics Features - Jun 18, 2025When an Instanced Static Mesh Component (ISMC) uses a material with a non-zero Max World Position Offset Displacement, the bounds are correctly expanded at initialization. However, after calling Upd ...
[CrashReport] UE4Editor-UnrealEd.dylib!FEditorModeTools::MouseMove()
UE - Platform - Apple - Nov 21, 2017This is an infrequent Mac crash. Users have not provided any descriptions. Callstack from LogGeneratedClass '/Game/Maps/World.World_C' with ClassGeneratedBy '/Game/Maps/World.World:PersistentLevel. ...
Render target size mistmatch in ShaderDrawDebug
UE - Graphics Features - Jun 9, 2020We found a d3d debug validation assert in RDG_EVENT_NAME("ShaderDrawDebug"), with the full DLSS integration. It however also reproduces in (4.25.1-release, dev-rendering and the plugin branch with ...
Add Code to Project fails to add a class to the project
UE - Foundation - Core - Mar 16, 2015Add Code to Project fails to add a class to the project. The project can't be reopened until the classes are manually removed and the project is recompiled. The following errors occur when using Add ...
Crash While Compiling Blueprint in FBlueprintEditorUtils::RefreshExternalBlueprintDependencyNodes()
UE - Gameplay - Blueprint - Jun 7, 2016Having an actor blueprint (A) that contains an array variable of references to another actor (B) that is connected to a Length node and a Vector array that is connected to a ForEachLoop causes bluep ...