Unreal Engine Issues

UEditorEngine::OnAllPIEInstancesStarted() called prematurely, multiple times, while PIE clients are starting

Context UEditorEngine::OnAllPIEInstancesStarted() is a virtual function that gets called when launching Play-in-Editor. It can be overridden if the game project chooses to introduce a subclass of U ...

[Enhanced Input] The action instance data is incorrectly reset when you call "Add mapping context" on the same mapping multiple times

This is somewhat related to [Link Removed] and was brought up by a [Link Removed] Setting the CVar input.bRespectIMCPriortyForTriggers to false resolves the issue, but would re-introduce [Link Remo ...

The public header file ModelingToolsEditorModeToolkit.h exposes private module definition of ENABLE_STYLUS_SUPPORT

Character unnecessary step down during PHYS_Flying mode

When MovementMode is set to PHYS_Flying, the character may unexpectedly step down by MaxStepHeight when colliding with a wall near a ceiling. This occurs because UCharacterMovementComponent::StepUp ...

'Hide Unconnected Pins' Button in the Blueprint Node Details Panel Disconnects SubPins with Connections

Given a get node with a struct output, if "Split Struct Pin" is used on the struct and one of that struct's outputs are connected to another node, it does not count as a used pin when the base get n ...

Lumen Global Distance Field Trace Leaking due to Surface Cache Sampling

At specific distances from a thin wall, surfaces inside of a sealed chamber can receive indirect lighting from outside, leaking light into the chamber. This appears to be due to how SWRT handles sa ...

Call In Editor functions not working in blueprints

Context When selecting a component on an actor, any CallInEditor functions on the component's class appear as buttons in the details panel. Problem The CallInEditor functions don't execute in Blu ...

A chaos vehicle that moves at very high speeds with CCD enabled on the vehicle sometimes has a collision response that is abnormal where the vehicle loses a significant amount of speed when colliding with dynamic objects configured as One Way Interaction

Context: Continuous Collision Detection (CCD) is being used on a Chaos Vehicle to avoid tunneling issues with certain surfaces as it prevents any missed collisions between fast moving particles and ...

Issue with Niagara emitter inheritance

Modules in the particle spawn stage get unlocked and lose inheritance after changing the inherited emitter's interpolated spawn mode to "No Interpolation" then resetting. ...

Unreal Engine Fails to Launch with Vulkan SM6 RHI and RenderDoc Auto-Attach Enabled

When launching Unreal Engine with the Vulkan RHI, SM6 and RenderDoc Auto Attach on Startup enabled, the engine fails to initialize with the error: “A compatible Vulkan Driver is required to run the ...