Unable to run UE4Editor using the -SM4 commandline argument

Rendering - Nov 16, 2018

Attempting to run the UE4 Editor using SM4 causes an error to popup stating that "A Feature Level 5 video card is required to run to Editor. AvailableFeatureLevel = SM4, ShaderPlatform = PCD3D_SM4" ...

Crash when enabling "Support Material Layers" and adding an actor with a widget component to the scene

Rendering - Nov 13, 2018

The editor crashes when adding an actor to the level that contains a widget component (the class has to have been set (if the class is set to none the crash will not occur)) and the setting "Support ...

Rect Light Source Creates Black Artifacts When Overlapping a Mesh While Light Shaft Bloom Is Enabled

Rendering - Nov 9, 2018

A black line will appear If a Rect Light is overlapping a mesh while a Directional Light has light shaft bloom enabled. This line will originate from where the edge of the source is overlapping the ...

Progress Percent is removed from UMG Progress Bar when Transform Shear value is changed

Rendering - Nov 8, 2018

Modifying the Shear values on a Progress Bar in a Widget Blueprint cause it to lose its Fill Color and set Progress. This is a regression from 4.20.3 (CL-4369336). Reproes with -vulkan on both Linux ...

Billboard Component Flickers Between Textures When Using Set Sprite Node

Rendering - Nov 8, 2018

When using a Set Sprite node with a billboard component, the texture assigned will flicker between the two possible textures. Working as expected in 4.20 CL# 4369336 Found in 4.21 CL# 4541578, 4.2 ...

Mesh is not displayed when duplicating Hierarchical Instanced Static Mesh

Rendering - Nov 5, 2018

Mesh is not displayed when duplicating Hierarchical Instanced Static Mesh. It is displayed by editing the Transform of Instances. This problem does not occur in 4.19. It seems to happen in 4.20 and ...

bPersistentLines is not respected by DrawDebugLine

Rendering - Nov 1, 2018

It looks like the line's lifetime is forced to the default line lifetime of one second if the provided lifetime is less than zero, which would be the case if calling the function with just enough pa ...

Packaged Builds with DX12 Crash on 2nd Start

Rendering - Oct 18, 2018

Running a packaged game with DX12 will crash on launch every second start and after. If you delete the files with the .ushaderprecache extension that are in the ProjectName/Saved folder the exe star ...

Crash launching project with Compat.MAX_GPUSKIN_BONES=75 and Preview Rendering set to Shader Model 5

Rendering - Oct 18, 2018

Crash occurs when the user launches a project with a +75 bone skeletal mesh actor in their scene with the Compat.MAX_GPUSKIN_BONES=75 config change, and the default preview render is Shader Model 5. ...