Unreal Engine Issues
Unreal Engine Issues
Niagara system loses source emitters when moving Engine from 4.22 or earlier to 4.23 or later.
UE - Niagara - Nov 29, 2019The following code causes this behavior.// NiagaraSystem.cpp for (FNiagaraEmitterHandle& EmitterHandle : EmitterHandles) { EmitterHandle.ConditionalPostLoad(NiagaraVer); if (!EmitterHandl ...
Problems in skeletal mesh merge
There are a few issues a licensee has found with the skeletal mesh merge operation. See the UDN for more details and the proposed fixes. Note, the issue with the cloth merge is already logged in a ...
bIgnoreAllPressedKeysUntilRelease only applies to keys in the previous mapping
UE - Gameplay - Input - Jun 16, 2022This is because the RebuildControlMappings function only checks this flag when you have a mapping that was already added, we should apply this for any new mappings as well. I'll update the repro s ...
Disabling bLerpUVs in Nanite Settings of Static Mesh causes texture warping in clusters
UE - Graphics Features - Nanite - Jan 21, 2025The licensee has identified a potential fix by changing if( Settings.bLerpUVs ) to if( Settings.bLerpUVs || UVIndex == 0 ) On line 389 of NaniteBuilder\Private\Cluster.cpp in UE 5.5 ...
Copy-pasting custom property nodes (ControRig etc.) results in invalid bindings, perf issues
UE - Anim - Rigging - Control Rig - Jul 28, 2025From this UDN: [Link Removed] Suggested fix:Override PostPasteNode to perform the GUID update andAdd validation on load to strip 'invalid' copies that do not correspond to a valid pin input ...
Crash when using a Self reference with a Custom Event variable
UE - Gameplay - Blueprint - Jan 19, 2017Crash when using a Self reference with a Custom Event variable that is using Pass By Reference. The crash only seems to occur if the setup was created in the Player Controller class. This was origi ...
Crash editing Landscape Splines with Level Sequence Open
Tools - Mar 6, 2017A crash occurs when attempting to transform a landscape spline with a Level sequence open. It is important to note that no key framing or animating of the landscape spline control point is occurrin ...
Editor crashes when BP spline component is selected
Tools - Jan 12, 2017When a spline component point is selected, attempting to select another spline component will cause the editor to crash. Crash also occurs if the same component is selected. Workaround: If the emp ...
Crash occurs in UMG Animation after pressing "Home" key and RMB the timeline
UE - Anim - Sequencer - Oct 17, 2016This was able to be reproduced 100%. I encountered this during a Regression pass. I was trying to give myself more working space and remembered that hitting "Home" focused the space in sequencer, so ...
Crash when opening Blueprint after editing ChildActorComponent base class
UE - Gameplay - Components - Feb 7, 2017Defining a ChildActorComponent in code, then setting the component to a blueprint derived from another code class causes the editor to crash when opening the parent blueprint if any changes are made ...