Mesh Paint can fail to find vertices using physics collision query

Tools - Oct 8, 2019

Mesh paint is for painting the vertices of a mesh, but in part uses physics collision queries to detect hits and search for vertices. (see FMeshPaintGeometryAdapterForSkeletalMeshes::LineTraceCompon ...

Encryption handshake will fail if a seamless travel occurs during key lookup

UE - Networking - Oct 4, 2019

The encryption token challenge/response portion of the control channel handshake can fail due to a seamless travel occurring between the client's NMT_Hello being received by the server and the serve ...

Playing as a Pawn that is a Duplicate of a Blueprint Class doesn't create an Attribute Set

UE - Gameplay - Oct 1, 2019

Creating a duplicate of a Blueprint class that has an AttributeSet seems to be interfering with the creation of the AttributeSet. ...

Divide by zero in beam update can cause editor to crash in Cascade

UE - Rendering - Niagara - Sep 23, 2019

The licensee has traced the issue back to a divide by zero in  UParticleModuleTypeDataBeam2::Update. If the Target and Source are the same then the beams magnitude will be zero. When there is a Nois ...

Landscape Layer Blend generates bad code for preview shader

UE - LD & Art - Modeling Tools - Landscape - Sep 23, 2019

It breaks only when compiling the preview shader. Adding a preview weight to the Layer0 on the Layer Blend node fixes the problem. The source of the bug is in UMaterialExpressionLandscapeLayerBlend ...

Renaming Sprite Actor in Struct Blueprint, and closing the Editor causes de-reference

UE - Gameplay - Sep 12, 2019

Paper Sprite actor set as a Default Value in a Blueprint Struct is set to none, when the sprite is renamed, saved, and the Engine is restarted. ...

Memory leak with disable rendering

UE - Rendering - Sep 2, 2019

When executing "ShowFlag.Rendering 0", it occur the memory leak because it can't run RHICmdList.ImmediateFlush(). The following code is a workaround. DEC_MEMORY_STAT_BY() is ImmediateFlush. Witho ...

State Machine events "Left State Event" and "Fully Blended State" not firing when animation is sequence is playing

UE - Anim - Gameplay - Aug 28, 2019

State Machine events "Left State Event" and "Fully Blended State" not firing when animation is sequence is playing at the moment you enter/leave the state. ...

Confusing message when attempting to connect mismatched Delegate pins

UE - Gameplay - Blueprint Editor - Aug 26, 2019

When the user attempts to connect delegate pins that don't match, they received a confusing mouse tooltip message that simply reads "Delegate is not compatible with Delegate". Suggested fix: When ...

Spelling error of Boolean "continuous" in Task Node "Move to Location or Actor"

UE - AI - Aug 14, 2019

Spelling error of Use Continuous Goal Tracking Boolean "continuous"  in Task Node "Move to Location or Actor" ...