Lighting behavior is unreliable for translucent lit materials, results are inconsistent depending on the editor camera's FOV and the editor viewport's width/height/aspect

UE - Rendering Architecture - Oct 27, 2024

When working on the level editor viewport or testing on PIE, the visual appearance of additive/translucent lit materials changes significantly (and abruptly) when varying the camera FOV or the viewp ...

Crash in FPipelineFileCacheManager::RegisterPSOStats

UE - Rendering Architecture - Oct 25, 2024

The game can crash when one thread clears RunTimeToPSOUsage while another thread is expecting it to contain a PSO it is registering stats for. Thread A:  calls CacheGraphicsPSO() Thread B:  calls C ...

ChaosCacheManager is not properly recording the state of each particle when toggling Fields and Anchor Fields in the scene.

UE - Simulation - Physics - Destruction - Oct 22, 2024

ChaosCacheManager is not properly recording the state of each particle when toggling Fields and Anchor Fields in the scene. During my investigations I've noticed that ChaosCacheManager does not reco ...

A GeometryCollection that was broken and is going through shrinking will reset the size of its particles if a second level is broken

UE - Simulation - Physics - Destruction - Oct 18, 2024

Might relate to issue [Link Removed] - "The Remove-On-Break feature, set on Fracture Mode on Geometry Collections, stops shrinking and shows strange behaviors" The added information on this particu ...

Lumen doesn't handle Area Lights Reflection Occlusion well

UE - Graphics Features - Lumen - Oct 18, 2024

Crash (Assertion failed "SystemInstanceController->IsSolo()") when enabling "Start with Tick Enabled" on a Niagara Component

UE - Niagara - Oct 17, 2024

Currently, Niagara Components are only expected to have their TickComponent() method called when their system is marked as "Solo", which makes them be simulated individually. In the most common scen ...

A Packaged build that has had an Editor Only Component added to one of its Blueprints logs a false positive warning - USimpleConstructionScript::FixupRootNodeParentReferences()

UE - Framework - Components - Oct 15, 2024

A Packaged build that has had an Editor Only Component added to one of its Blueprints logs a false positive warning in USimpleConstructionScript::FixupRootNodeParentReferences(): USimpleConstructio ...

Decals custom depth/stencil side effect from Lumen

UE - Graphics Features - Oct 15, 2024

The order of passes related to Decal rendering (without the DBuffer) and CustomDepth is changed by the CVar "r.Lumen.AsyncCompute", even when Lumen is not enabled. This causes Decal Materials that ...

In Standalone mode, when reading world partition actor descriptors for BP actors, "bIsSpatiallyLoaded" receives its value from the native base class instead of the BP class, so BP actors are loaded/unloaded based on the wrong condition.

UE - World Creation - Worldbuilding Tools - World Partition - Oct 15, 2024

Consider an actor defined in C++ with "bIsSpatiallyLoaded" set to true (the default), and a derived blueprint that overrides "bIsSpatiallyLoaded" to false. Now consider an actor instance of that blu ...

The Remove-On-Break feature, set on Fracture Mode on Geometry Collections, stops shrinking and shows strange behaviors

UE - Simulation - Physics - Destruction - Oct 15, 2024

The Remove-On-Break (ROB) feature, set on Fracture Mode on Geometry Collections (GC), was supposed to make the particle shrink until it vanishes. When the GC goes to sleep the shrinking stops and sh ...