Unreal Engine Issues

FHLSLMaterialTranslator::GetMaterialEnvironment can crash or not load UMaterialParameterCollections

In UE 5.5, the Editor may crash in FHLSLMaterialTranslator::GetMaterialEnvironment when loading materials with Material Parameter Collections, likely due to async loading. Calling ParameterCollectio ...

Find in Blueprints: Default values in struct members are not returned

Context Find-in-Blueprints can be used to search the current, or all, blueprints. If you enter a simple string, it would return nodes, pins, pin default values and default values for BP Variables ( ...

[Interchange][glTF] Morph animations are not imported

[Link Removed] From the UDN: When importing a glTF file from Blender with both skeletal and morph animations, only the bone animations are imported - the morph animation curve is completely missing ...

Runtime virtual texture sometimes shows corrupted tiles

Some licensees have reported seeing intermittent corruption of runtime virtual texture tiles. This hasn't been reproduced at Epic. Usually this shows up as some small percentage of rendered tiles l ...

A partially broken Geometry Collection ends up with garbage CollisionGroup data that can lead to strange behaviors

A partially broken Geometry Collection (GC) ends up with garbage CollisionGroup data that can lead to strange behaviors. The licensee has noticed that a GC that goes thru a field applying ExternalS ...

FieldOfView and AspectRatio shouldn't be animated on Cine Camera Actors

Crash when exporting static mesh actor to FBX (Array index out of bounds)

I set the Forced LOD Model on the mesh component > 1, then tried to export, this is what causes the crash. Here is my suggested fix, we just don't use Git or I'd do a PR: In the else() branch of FF ...

Engine no longer compiles after backporting RHI thread improvements and crash fix

Unreal Engine 5.4 code will no longer compile after applying both the RHI improvement code changes as described in [Link Removed] and the fix for the crash described in [Link Removed]. The compilati ...

Launching multiple Editor processes in UE 5.5 can throw warnings due to USD Core plugin initialization

Launching multiple Editor processes at the same time with the USD Core plugin enabled can cause warnings to be logged like the following:LogUsd: Warning: Failed to update LibraryPath for USD plugInf ...

Divergent group barriers in Lumen

Intel reported GPU crashes on their hardware caused by divergent group barriers in ScreenProbeConvertToIrradianceCS:[numthreads(THREADGROUP_SIZE, THREADGROUP_SIZE, 1)] void ScreenProbeConvertToIrra ...