Instance Static Meshes spawned at Runtime do not have collision

UE - Gameplay - May 8, 2015

Spawning an Instance Static Mesh at runtime does not have collision. This issue appears only in 4.8 Preview 1 and the 4.8 Release branch (tested on CL-2540862), but is fixed in Main Branch as of Ma ...

AI Move To Location zeros velocity each call, causing the AI Pawn to freeze if told to move again before reaching destination

UE - AI - Sep 12, 2016

AI Move To Location causes AI to lose velocity each time it is called, resulting in a freeze in movement on each call. Regression: Yes Worked: 4.12.5 (CL 3039270) Broken: 4.13.0 (CL 3106830) Funct ...

-binnedmalloc is broken on Linux

UE - Platform - Linux - Oct 31, 2016

In 4.13 launching a linux game with -binnedmalloc will use the binned allocator. In 4.14 the command line was accidentally changed to -binnedmalloc1 while making other changes. It is still -binnedm ...

Content Examples: Blueprints_Overview Stand 1.7 Spark particle system does not fire from coin

Docs - Samples - Jan 19, 2017

During runtime, the red coin in Stand 1.7 on the Blueprints_Overview map of Content Examples should emit a large spark particle system 5 times. While investigating, I tried disabling "Use Fixed Rel ...

Map load stalls in texture streaming code

UE - Graphics Features - Jun 13, 2017

A change was made to AActor.GetComponents which appends the results instead of resetting the output array. This seems to only impact 2 places in the code, and has a big side effect in the texture st ...

meshes from 3ds Max which have custom pivots do not reappear in the level after undoing a delete action

UE - Editor - Content Pipeline - Datasmith - Exporters - Mar 29, 2018

There is an issue occurring where meshes from 3ds Max which have custom pivots from a datasmith import do not reappear in the level after deleting them and then undoing the delete action. The mesh d ...

Spawned particles on the surface of a static mesh in Niagara get offset if the actor is anywhere but the world origin

UE - Niagara - Jun 11, 2018

Particles that are spawned using the surface of a static mesh will be offset from the systems placement in the world unless it is at world origin.  Working as expected in 4.19 CL# 4033788 Found in ...

"Expose on Spawn" variables in Actor Components are overridden by the details value.

UE - Gameplay - Aug 2, 2018

"Expose on Spawn" variables in Actor Components are overridden by the value set in their Details Panel when called in another Blueprint. This issue was reported and tested in 4.20.1 (CL-4233996). ...

PIE gets stuck on infinite loop when Background Streaming is disabled

UE - Foundation - Core - Aug 24, 2018

When "Use Background Level Streaming" is disabled, the Editor gets stuck loading in PIE when you press Play. This is a regression from 4.19.2 (CL-4033788). This issue was reported and tested in 4.2 ...

Unimplemented Simplygon function causes empty mesh LODs and crashes

Tools - Aug 31, 2018

When we do the refactor for MeshDescription we miss the staticmesh reduction project settings option and change only the quadric reduction. There are two possible fixes for this issue: 1. Implemen ...