VisualizeTexture with the BMP flag causes a crash when any mip over mip0 is requested

UE - Rendering Architecture - RHI - Dec 18, 2024

When a mip level higher than 0 is requested in VisualizeTexture, the engine will crash. The root cause appears to be VisualizeTexture.cpp:924, on which an incorrect mip level is used to read a non-m ...

Modifying the properties of a ChildActorComponent in a child blueprint can modify the parent actor ChildActorComponent properties.

UE - Gameplay - Blueprint - Dec 10, 2024

When a property of a ChildActorComponent is modified in a child class, the parent ChildActorComponent class can also get modified. This happens when the Parent blueprint actor has a ChildActorCompo ...

Users are unable to create projects when the default project location is a networked drive

UE - Editor - Workflow Systems - Oct 23, 2024

There have been multiple reports of this issue, particularly from schools, over the last 10 years:https://forums.unrealengine.com/t/invaild-folder-path-with-network-user-drives/283475https://forums. ...

CSM shadow casters falsely culled due to incorrect primitive octree test

UE - Graphics Features - Shadows - Sep 13, 2024

While setting up whole scene shadows, CasterOuterFrustum is used to cull shadow casters from PrimitiveOctree. CasterOuterFrustum doesn't extend far back enough, which means that if an octree node fi ...

Regression: "Object Position" node in Light Function materials did not compile up to UE 5.0. Starting with 5.1, it compiles but outputs garbage values

UE - Rendering Architecture - Materials - Aug 26, 2024

Up to UE 5.0, when the "Object Position" node is used in the Material Editor as part of a material with Light Function domain, attempting to compile the material results in the following error: "[SM ...

Tracks that manipulate byte properties may have different (non-deterministic) results even for the same frame

UE - Anim - Sequencer - Aug 13, 2024

This issue is relatively easy to reproduce, e.g., in the timing of switching between the two types of property operations within the same track. It seems to be easy to reproduce the above problem in ...

CharacterMovementComponent - Jump incorrectly simulated when moving against a wall, resulting in an apex height lower than expected and framerate-dependent

UE - Gameplay - Jun 17, 2024

The CharacterMovementComponent simulates the position of a jumping/falling character inside function UCharacterMovementComponent::PhysFalling() [CharacterMovementComponent.cpp:4381]. On the main cod ...

Lyra: GA_Melee uses disallowed NetMulticast RPC for melee impact sound

UE - Gameplay - Gameplay Ability System - Jun 13, 2024

The melee gameplay ability GA_Melee uses a NetMulticast RPC which isn't allowed and causes a blueprint validation error: GA_Melee.uasset: Gameplay Abilities are not replicated to Simulated Proxies ...

SpringArmComponent with "Use Camera Lag Substepping" does not handle fluctuating frame rates correctly

UE - Gameplay - Jun 4, 2024

The description of SpringArmComponent's "Use Camera Lag Substepping" option says "sub-step camera damping so that it handles fluctuating frame rates well". However, as noted and explained by a licen ...

Nanite mesh shadows not updating when CSMCaching enabled

UE - Platform - Mobile - May 25, 2024

A Nanite primitive casting a CSM shadow on another Nanite primitive with "Cast Shadows" disabled, will have it's shadow disappear completely when r.Shadow.CSMCaching = 1. ...