Unreal Engine Issues
Unreal Engine Issues
Bug in StringTemplate.cpp related to modulo operator in MaterialTemplate.ush (code fix provided)
UE - Rendering Architecture - Materials - Jun 25, 2024Shader Template files like MaterialTemplate.ush do not submit previous chunks when encountering a `%` character, unless that `%` character is `%s` or `% {...} `. Because the error is happening ...
Local binary build fails for iOS platform.
UE - Foundation - Core - Oct 5, 2017Attempting to create a local binary build of the Engine for the iOS platform using BuildGraph is currently failing. While trying to build UHT for Mac using a remote build, the build fails because it ...
ACineCameraAttachMount's "Target Actor" constraint does not work with Spawnables or Replaceables in Sequencer
UE - Virtual Production - Tools - Virtual Camera - Aug 12, 2025Constraints (UTickableConstraint) are usually created throuh the "Animation" tab available in the Editor's "Animation Mode". When created through that interface while Sequencer is open, the internal ...
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 ...
Unable to interact or collide with geometry collection after Removal on Sleep or Break timer finishes, yet unbroken piece continue to render
UE - Simulation - Core - Dec 18, 2025Context: A static mesh is able to have a geometry collection generated from it using the Fracture editing mode. It can be fractured in many different ways, and when acted upon by a chaos field agent ...
A welded hierarchy blocks updates to collision settings on all but the root primitive. Calling SetCollisionResponseToChannel on the children won't work.
UE - Simulation - Physics - Nov 22, 2024A welded hierarchy blocks updates to collision settings on all but the root primitive. Calling SetCollisionResponseToChannel on the children won't work. The licensee noticed that IPhysicsProxyBase* ...
The Color Picker in the Material Editor doesn't pick colors from windows outside of the editor anymore
UE - Rendering Architecture - Materials - Nov 19, 2014The Color Picker/Eye Dropper in the Material Editor doesn't register colors from any windows outside of the editor anymore. Changelist #2337679 (Not working here of any changelist created after it ...
CharacterMovement doesn't clear velocity
UE - Simulation - Physics - Oct 11, 2024Velocities are not being cleared when physics simulation set to false. ...
Crash when using Landscape when building lighting with commandlet
UE - Graphics Features - Jun 6, 2016When using the new Rebuild Lighting commandlet will cause a crash with any level that builds when it has a landscape in the scene. https://github.com/EpicGames/UnrealEngine/commit/f89256dd0efb7d0b ...
Structure variables in Child Blueprints do not maintain the default values set in their Parent Blueprints
UE - Gameplay - Blueprint - Jan 12, 2015Values changed to an inherited Struct variable in a Child Blueprint will be kept after compile, but any not changed will be set to 0s. ...