IsTraceHandleValid with default FTraceHandles has unexpected behavior on the first frame

UE - Simulation - Physics - Sep 18, 2018

Because both FWorldAsyncTraceState's CurrentFrame and FTraceHandle are default initialized to 0, on the first frame, if a new Asnc Trace starts all default FTraceHandles will reference the same (now ...

An Actor BP with an editable variable that references another Actor in the level will reference multiple examples of that Actor if it is duplicated

UE - Gameplay - Blueprint - Mar 13, 2015

An Actor BP with an editable variable that references another Actor in the level will reference multiple examples of that Actor if it is duplicated. Reproduced in 4.7.2 binary and Main (//depot/UE4 ...

Moving Child Object in Local Space Causes Flickering

Tools - Jun 30, 2016

When moving an object in the viewport that is parented to another object with a scale of -1,1,1, the child object will flicker. This is a regression, this did not occur in the 4.11.2 binary release ...

UCommonVideoPlayer/Electra does not work in 5.3

UE - Media Framework - Jan 30, 2024

This appears to be connected to playing immediately upon opening. This behavior is not observed when in the Release-5.1 or Release-5.2 streams. With the same setup, the video will start playing on t ...

[Audio Modulation] - Ensure is thrown when attempting to modulate a Source Effect at runtime

UE - Audio - Modulation - Sep 6, 2023

Does *not* occur in editor. Only in standalone and runtime. Occurs when modulating Chorus or Bit Depth Also occurs in 5.2 and 5.3. I also noticed the test with this is supposed to set the chorus e ...

Visual glitches on Mac OS X using an Intel GPU while playing HW accelerated H264 video

UE - Graphics Features - Dec 2, 2014

This looks to be a system driver bug, but logging here for transparency and future reference. It took me a long while to figure out that the key issue is a conflict during blit between UE4 and the H ...

While a Custom Event's delegate pin is connected to anything its details are not visible in the Details panel

UE - Gameplay - Blueprint - Oct 27, 2015

While a Custom Event's delegate pin is connected to anything its details are not visible in the Details panel. Tested with an empty reroute node as noted below as well as a Set Timer node. Reproduc ...

Timeline name changes do not propagate to related nodes

UE - Gameplay - Blueprint - Mar 17, 2015

Timeline name changes do not propagate to related nodes. Refresh All does not rename nodes that reference the timeline, and Getters and Setters are no longer valid nodes. Reproduced in 4.7.2 binary ...

Blueprint Doesn't Show Components Added at Runtime

Tools - Nov 2, 2015

When a custom component is added at runtime, it does not show up in the details panel when you select the blueprint that it has been added to. Found in 4.9.2 binary. Reproduced in 4.10 Preview 3 a ...

HLSLCC crashed on parsing UAV related instruction

UE - Graphics Features - Oct 10, 2019

1.glsl_type with image was not fully inited with HlslName field set, causing the crash 2.seems many types of op are not support by current hlslcc, cause error msg. e.g. RWTexture2D.Load[Image Remo ...