Using Tortoise SVN causes the engine's source control to be inconsistent

Tools - Jun 16, 2015

If a user decides to use Tortoise SVN, the error messages given for needing to have things checked out is inconsistent. If there is a blueprint which references another blueprint, and the reference ...

Actors not marked as Always Relevant do not replicate to Clients that have possessed a vehicle past 15,000 units of the point of possession

UE - Networking - Oct 20, 2015

Actors not marked as Always Relevant do not replicate to Clients that have possessed a vehicle past 15,000 units (the sq root of Net Cull Distance Squared) of the point of possession. Note that repl ...

UE4Editor_SlateCore!TSharedFromThis<SWidget,0>::AsShared() sharedpointer.h:1221

Tools - Apr 18, 2017

This bug report was entered as new crash groups appeared linking to [Link Removed] which was marked as fixed for 4.15.1 and the previous reproduction did not reproduce the issue Error message: Ass ...

Float Curve evaluation may yield completely wrong results due to floating-point precision issue

UE - Runtime - Animation - Oct 31, 2024

Note: This is possibly related to [Link Removed] Backlogged . For some inputs, function UE::Curves::WeightedEvalForTwoKeys( ...

Reference to control rig can be lost on actors with multiple skeletal mesh components

zComponent - Archive - Apr 4, 2023

In 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 - Core - Systems - Jul 30, 2020

The 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 ...

[CrashReport] Assertion failed: TaskDataArray.Num() == Exporter->VolumetricLightmapTaskGuids.Num()

UE - Graphics Features - Lumen - Oct 2, 2017

This is a trending crash coming out of the 4.18 Previews. Users have not provided any descriptions of their actions when the crash occurred, but at least two of the affected projects are being creat ...

Cannot select child anim BPs for use in linked anim layers

UE - Runtime - Animation - Jul 15, 2021

From 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 - Rendering - Features - Jun 18, 2025

When 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 ...

Crash on Adding Texture Samples with modified BasePassPixelShader.usf

UE - Graphics Features - Jul 27, 2015

In 4.8.2 QA Build - Making the changes to BasePassPixelShader.usf listed below, adding two texture samples and then using the Preview Arrow toggle on the add node will hard crash the CPU, requiring ...