Unreal Engine Issues
Unreal Engine Issues
Buoyancy is broken in UE5: even BP with Cube SM component (mass is 1kg) and default Buoyancy Component with one default Pontoon falls on bottom of lake
UE - Runtime - Deformable - Jul 26, 2021Shorter steps:Steps 1-8 from Steps to reproduce (create level with water body)Find BP_BuoyancyExample in Content Browser (Engine>Plugins>Water Content>Blueprints)Place BP_BuoyancyExample above the w ...
UAnimNotify::Notify not called during USkeletalMeshComponent interaction with UPhysicsControlComponent when PhysicsBlendWeight is zero
UE - Anim - Synthesis - Physics Control - Mar 30, 2025UAnimNotify::Notify not called during USkeletalMeshComponent interaction with UPhysicsControlComponent when PhysicsBlendWeight is zero. The licensee has provided his analysis of the code: If USkelet ...
Variant manager crash in UPropertyValue::HasValidResolve
UE - Editor - Content Pipeline - Variants - Nov 21, 2024in the past we have reported a lot of VM related bugs which got fixed over time. Unfortunately, I think we have another one. Right now we're using 5.0.3 binaries from the launcher. Now the pro ...
Using the end of the curve as a weighted tangent does not yield the expected value.
UE - Runtime - Animation - Oct 16, 2023When changing the tangent value, the last value is sometimes not 1.0 [Reproduce sample project] [Link Removed] ...
BlendListByEnum assumes that enum values are sequential
UE - Runtime - Anim BP - Aug 26, 2024FAnimNode_BlendListByEnum assumes that values within a custom enum type are sequential (ie. the index 0 = value 0, index 1 = value 1). But this is not true of all custom enum types, for example: U ...
Curve Atlas Row Parameter uses derivative ops when Texture Sample connected to curveTime input
UE - Rendering - Architecture - Materials - May 1, 2026When a Curve Atlas Row Parameter node is used with a Texture Sampler connected to the curve time input, the sample type uses derivative ops. This has negative performance implications for Nanite co ...
Point light missing issue on PowerVR GE8xxx when GPUScene is enabled
UE - Platform - Mobile - Sep 17, 2025On PowerVR GE8xxx devices (e.g., GE8320), running with GPUScene enabled on the OpenGL ES path, point/local Lights render nothing or significantly weak result. Withouy GPUScene(UniformView/UBO path), ...
The pak file specified in PakFileRules is not created correctly
UE - Core - Systems - Aug 8, 2023The rules by which chunks are created are ambiguous and currently do not ensure that both PakFileRules and PrimaryAssetLabel settings are reflected. In this sample, depending on the PrimaryAssetLabe ...
Deadlock in UPhysicalAnimationComponent::UpdatePhysicsEngineImp
UE - Runtime - Simulation - Sep 13, 2023Deadlock in Chaos during PIE; the main thread is in USkeletalMeshComponent::HandleExistingParallelEvaluationTask waiting for a task to complete, and a worker thread is running that task and is in US ...
Geometry Collections built with "Use Root Proxies" rendering/transform positions ignore the original root node rotation and can lead to unexpected behaviors
UE - Runtime - Deformable - Nov 17, 2025Geometry Collections (GC) built with "Use Root Proxies" rendering/transform positions ignore the original root node rotation and can lead to unexpected behaviors. If the root node of the GC was rot ...