Unreal Engine Issues
Unreal Engine Issues
Delta struct serialized fast arrays replicating new elements with no changelist
UE - Networking - Jun 14, 2021There is a scenario where delta struct serialized fast arrays can replicate changes that introduce additional elements to the array, but without changelists containing the new data. This needs furt ...
When used with First Loop Start Frame Offset and Use Animation Blueprint, the character will alternate between the specified animation and the reference pose
UE - Anim - Anim in Engine - Jan 30, 2023If you use StartFrameOffset set to 1 or higher in conjunction with the Use Animation Blueprint, the character's animation will be rough towards the end of the section. Specifically, it seems that th ...
Crash when calling FillDataTableFromCSVString() while viewing the contents of the data table
When the function UDataTableFunctionLibrary::FillDataTableFromCSVString() is used from Editor Utility Blueprints or Python Scripts, and the contents of the affected Data Table are currently being vi ...
IKRetargeting Skeletal Mesh Does Not Update Virtual Bones
UE - Anim - Rigging - Retargeting - May 20, 2022Occurs 5/5 times. Regression does not occur: UE5Manny Skeletons are new to UE5.0 ...
UNetDriver server-side hitch results in ActorInfo->NextUpdateTime far into future
UE - Networking - Feb 16, 2024A high UWorld::Tick DeltaSeconds (i.e. GameThread hitch) results in a high UNetDriver::TickFlush DeltaSeconds. This DeltaSeconds can high (many seconds) if the hitch is long. This value then affects ...
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, 2025Foreword: 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 ...
Blueprint with Niagara System and Skeletal Mesh Components Automatically Updates Niagara System Skeletal Mesh
UE - Niagara - Apr 4, 2019When adding a niagara system that reproduces a skeletal mesh and a skeletal mesh as components to a blueprint, the niagara system immediately updates its skeletal mesh to the most recently updated s ...
Shader compiler errors when using enclosed local variables in a material while ray tracing is enabled
UE - Rendering Architecture - RHI - Jan 23, 2020A licensee is seeing an issue with a couple of post process materials after enabling ray tracing. While the materials presenting the issue fail to compile for different reasons, they both refernce t ...
Memory leak when Lumen is disabled but r.MeshCardRepresentation=1
UE - Graphics Features - Lumen - Jul 29, 2024When Lumen is disabled, but the cvar "r.MeshCardRepresentation" is set to 1, Lumen will continuously enqueue object removal from the Lumen Scene, without ever emptying the array of primitives to rem ...
Attempting to set skeletal mesh on vehicle blueprint during PIE crashes editor
UE - Simulation - Physics - Feb 8, 2016Switching the skeletal mesh of an actor during PIE crashes the editor. Frequency: 5/5 Crashreporter: N/A ...