Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage

UE - Niagara - Feb 28, 2025

Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...

Animating blueprint mesh duplicates uncontrollably

UE - Gameplay - Components - Apr 15, 2015

When animating within a blueprint of a subclass created in c++, the animating mesh replicates itself uncontrollably. Added to .h: UPROPERTY() UBoxComponent* BoxComp; UPROPERTY() USkeletalMeshCompo ...

After Seamless Server Travel, the Client cannot move the character or see the Server character

UE - Networking - Jul 9, 2015

After Seamless Server Travel, the Client cannot move the character or see the Server character. On the Server, the Client character appears to be falling in place. Tested in both first and third per ...

AbilitySystemComponent::NotifyAbilityEnded Can Crash due to Callbacks Invalidation Specs

UE - Gameplay - Gameplay Ability System - Oct 11, 2023

Pasting from the UDN: Unsafe code in AbilitySystem can lead to crash when granting an ability inside OnAbilityEnded Hello. We just ran into a crash. After investigation, it seems to be caused by ...

Sprite collision is inaccurate

UE - Gameplay - Paper2D - Oct 31, 2014

Sprite collisions do not accurately reflect the collision for the sprite. While the collisions are always the same between two of these, the collisions do not correspond to the shape of the collisio ...

CapsuleComponent Shape sometimes reverts to previous value after entering a new value

UE - Foundation - Core - Nov 28, 2014

If you manually type in the value for Capsule Half Height, it will sometimes revert back to it's previous value upon hitting Enter. The CapsuleComponent's shape in the Blueprint's Viewport adjust to ...

Crash while using Geometry Scripting to add an Array of Vector 2D data to 'Append Buffers to Mesh' node UV0 input pin

UE - Graphics Tools - Modeling Tools - Jun 13, 2022

Geometry Scripting plugin isn't available for 4.27.2, and the behavior is the same 5.0.1. Crash while using Geometry Scripting to add an Array of Vector 2D data to 'Append Buffers to Mesh' node UV0 ...

Building Nanite on a Landscape with Visibility Mask multiple times gives an Assert

UE - Graphics Tools - Terrain - Landscape - Aug 28, 2023

Repro Rate 15/25 Regression set to Yes as this was not found on //UE5/Release-5.2 CL 26001984 Binary Building Nanite with a Landscape that has a material including Landscape Visibility Mask still ...

Blueprint Cannot Give Niagara CPU Access To Skeletal Meshes Added From Blueprint

UE - Niagara - Apr 4, 2019

When a user tries to add a skeletal mesh component to a blueprint with a niagara system to use the skeletal mesh with that niagara system, the niagara system will stop rendering because it does not ...