Unreal Engine 4.20 Preview

I thought I saw it mentioned in a GDC talk that Epic would release the streamer they built for the ILM Xlabs raytrace demo for streaming to the Ipad to the general public in 4.20. Is this still in the plan? I don’t see it on the list.

Ok, that is encouraging, thanks!
And no I have not encountered any freezing in 4.19.


We have just released Preview 5 for 4.20! Thank you for your continued help in testing the 4.20 build before its official release. As a reminder, the Preview builds are for testing only, and should not be used for the active development of your project.

For a list of known issues affecting this latest preview, please follow the links provided on the first post in this thread.

Fixed in Preview 5
Fixed! UE-60538 Engine Test - Screenshot ‘AnimatedCloth’ test failed, Screnshots were different!
Fixed! UE-61299 Audio mixer memory leak
Fixed! UE-61303 Clicks with stopping voices in QAGame
Fixed! UE-61128 Synth Sample Player Crash When Setting Sound Wave During Playback On Long Files
Fixed! UE-60850 Stuttering audio when playing Short Beep sample
Fixed! UE-60913 Static sounds have severe hitching of sound in New Audio Engine on HTML5
Fixed! UE-60839 Audio is inaudible when Falloff Distance is set to 1
Fixed! UE-61309 CircularQueue Count method returns bad value when Tail wraps around
Fixed! UE-61058 Visual Studio not linked to Binary Editor
Fixed! UE-60726 Error occurs when attempting to create a local binary engine build that includes iOS
Fixed! UE-60969 UAT searches wrong root folder for include paths specified in .Build.cs
Fixed! UE-60962 Enabling a plugin in a BP project does not compile the plugin on restart
Fixed! UE-61182 Mac Core Components is 17GB with Preview 4
Fixed! UE-61249 Lighting needs to be rebuilt in ContentExamples - Lighting
Fixed! UE-60678 Disable FX option doesn’t disable all the sound FX
Fixed! UE-60673 Lots of clicking in ambient audio on Android
Fixed! UE-60583 Main menu doesn’t fade behind Options on Android
Fixed! UE-60953 Class Type References are listed twice in the description for Virtual Reality Templates
Fixed! UE-60943 Potions do not provide the recovery listed in the inventory
Fixed! UE-61142 ContentExamples - Lighting - 5.4 example needs to be updated to use SpecularScale
Fixed! UE-61120 Replace VirtualCameraSample project with VirtualCamera project
Fixed! UE-61147 Multiple unused assets and Redirectors in EngineTest
Fixed! UE-61082 Match3 fails to package for iOS with Binary Editor and Source build - bCompileCEF3
Fixed! UE-60658 iOS packages fail to build with incompatible Datasmith plugins
Fixed! UE-60937 Texture need to be reimported after importing MDL file
Fixed! UE-61157 nDisplay template have some bad settings
Fixed! UE-59042 Late feature : VRed importer
Fixed! UE-60946 Import CAD - Crash on reimport Datasmith scene after deleting light sources
Fixed! UE-61132 [Regression] Missing static mesh actors on importing CATProduct
Fixed! UE-61178 Media Bundle Scaling Issues
Fixed! UE-61102 ActorComponent.h BP Node Tooltip Typo on bReset
Fixed! UE-61156 Code projects fail to compile in Binary version of the editor - NavigationSystemBase.h(202): error C2143: syntax error: missing ‘;’ before ‘<class-head>’
Fixed! UE-60922 Nav Area class is reset after updating from 4.19.2 to 4.20 Preview 3
Fixed! UE-60924 The target for the “Should be Loaded” variable appears to have change to “Level Streaming Kismet”
Fixed! UE-61123 Text pins on call nodes not updated when default value changes
Fixed! UE-52940 Two nodes named Load Level Instance
Fixed! UE-61088 Text pins are not orphaned when it has a value
Fixed! UE-59040 Crash when calling a RPC function with a TSet or TMap parameter on a client
Fixed! UE-61003 DemoRec creates named folder demo2 instead of the expected demo1 named folder for empty Demo directories
Fixed! UE-61033 ShooterGame: Unable to return to Main Menu from Demo Replay
Fixed! UE-61031 Shootergame Demo List persists after Demos Start Playing
Fixed! UE-61181 Crash opening Physics Asset for a clothed skel mesh with assigned LOD Settings
Fixed! UE-61191 TLS slots can be shared due to issue with TStaticBitArray::FindFirstClearBit()
Fixed! UE-60993 Shootergame fails to build with LogShaderCompilers: Error: Errors compiling global shader FPostProcessDiaphragmDOFSetupCS
Fixed! UE-58827 TM-ShaderModels launch on process terminates with no logging after approximately 2 minutes
Fixed! UE-61121 ARM server fails to link missing openexr files
Fixed! UE-61115 Linux: Mono Process from UBT runs in the Background after Package is Cancelled
Fixed! UE-60879 does not automatically restart on Ubuntu 14.04
Fixed! UE-56041 Linux: Cancelling a package during build command prevents another package from being run
Fixed! UE-61190 UnrealMatch3 crashes when rotating while opening on IOS
Fixed! UE-60738 RemoteSessionApp is missing updated app Icons
Fixed! UE-58683 Custom iOS icons don’t appear on device for Windows BP projects (Binary Build)
Fixed! UE-58081 ARKit face AR - native orientation is Landscape, needs to match app
Fixed! UE-60928 RemoteSessionApp project fails to compile
Fixed! UE-59576 Blending on meshes in Landscapes umap is not rendering properly in High End Mobile Preview or HTMl5
Fixed! UE-59931 Blueprint iOS apps are named UE4Game.ipa
Fixed! UE-54781 Preache request should have been hot warnings opening QAGame
Fixed! UE-60605 Using the old DOF algorithm doesn’t work properly
Fixed! UE-60747 Basic StaticMeshActor components render discolored when undoing duplication
Fixed! UE-60764 [CrashReport] UE4Editor_Renderer!FMaterialShader::SetParametersInner<FRHIVertexShader * __ptr64>() [shaderbaseclasses.cpp:181]
Fixed! UE-60440 Infiltrator demo has very bright lighting on Mac
Fixed! UE-60425 Lights are not alternating their reaction on Lit Particles
Fixed! UE-60328 Translucency Lighting mode examples flicker in TM-ShaderModels
Fixed! UE-60380 Crash when running Editor with -vulkan - Error: Runnable thread RHIThread crashed.
Fixed! UE-60358 Animated Cloth rendering incorrectly in TM-ShaderModels - Mac Intel Iris Pro 6100
Fixed! UE-60169 [CrashReport] UE4Editor_Renderer!FMaterialShader::SetParametersInner<FRHIVertexShader * __ptr64>() [shaderbaseclasses.cpp:181]
Fixed! UE-60191 Launch-on and packages of TM-Shadermodels for iOS fail from missing Shader Maps
Fixed! UE-60965 Crash when setting the ‘Color Vision Deficiency Preview Type’ to anything other than Normal Vision on Mac
Fixed! UE-61106 Mac ComposureFramework project crashes on launch, Assertion failed: BufferIndex < 8
Fixed! UE-61105 GitHub 4829 : 4.20 dynamic hidden shadows fix
Fixed! UE-59505 Photorealistic Character aliasing results in jagged lines on skin and blotchy hair
Fixed! UE-57663 Vulkan crash when PIE in QAGame, vkGetQueryPoolResults failed with error VK_ERROR_DEVICE_LOST
Fixed! UE-52759 SwarmCoordinator and SwarmAgent can randomly fail writing to output directory in race condition during build
Fixed! UE-60964 Sequence Recorder Recording Groups have a “_A” appended after the user renames them.
Fixed! UE-61015 Control Rig Sequence doesnt have a default display rate
Fixed! UE-60991 Render movie settings not inheriting launch arguments from the editor
Fixed! UE-60976 Actor to Record in Sequence Recorder isn’t Filtering by Assets in the Level
Fixed! UE-61036 Crash when exiting a Sequence Recording in PIE if the Sequence Recorder window is docked to the left side of the editor
Fixed! UE-61074 Exposed default level sequence instance data to game C++
Fixed! UE-59820 Crash garbage collecting after saving a sequence with a duplicated binding
Fixed! UE-57712 Sequence Recorder: the sequence name of next sequence is not updated with next iteration when recording begins
Fixed! UE-61170 MeshDescription.Conversion test fails converting RawMesh to MeshDescription to RawMesh
Fixed! UE-60500 Staticmesh LODs custom SectionInfoMap give a different material mapping, build versus load
Fixed! UE-60301 The user is not warned when using content with broken normals due to encoding changes
Fixed! UE-61001 White frames on startup movies PC and XB1
Fixed! UE-61108 [CrashReport] UE4Editor_UnrealEd!FAssetEditorManager::OpenEditorForAsset() [asseteditormanager.cpp:386]
Fixed! UE-60952 Hovering Curve Gradient stop areas after creating a stop with Opacity = 0 hides the Curve Graident
Fixed! UE-61092 Startup Movies Black Screen in Packaged Projects
Fixed! UE-61085 High DPI Monitors and Editor Ruler
Fixed! UE-61098 //UE4-Release-4.20 - Incremental EngineTestEditor - warning: field ‘bUseMouseForTouchInEditor’ will be initialized after field ‘bShowTitleSafeZone’
Fixed! UE-60485 Removing a Foliage Type from a ProceduralFoliageVolume does not remove the Foliage Type from the volume when it is placed in a level
Fixed! UE-60958 Undoing and redoing erasing foliage will cause the foliage to flicker in the editor
Fixed! UE-59598 ContentExamples - SK_Box_Morph_1 has artifacting when animated
Fixed! UE-59611 Reimporting Static Mesh LODs yields unexpected material assignments
Fixed! UE-60549 LandscapeGrassOutput node doesn’t have name fields for Grass Types
Fixed! UE-58338 [CrashReport] UE4Editor_MaterialEditor!FMaterialEditorParameterDetails::GetParameterExpressionDescription() [materialeditordetailcustomization.cpp:365]
Fixed! UE-61241 Data interfaces defined in an emitter script can’t be used in a particle script in the emitter editor.
Fixed! UE-60688 Crash when deleting user exposed variables in system when created with parameter map
Fixed! UE-60390 Crash compiling Niagara Module script with a Curve Input Parameter
Fixed! UE-60995 [CrashReport] UE4Editor_NiagaraEditor!FNiagaraEditorUtilities::GetScriptOutputNode() [niagaraeditorutilities.cpp:823]
Fixed! UE-61087 Assert undoing the removal of an Emitter from a Niagara System with multiple Emitters
Fixed! UE-61012 Keeping Niagara GPU simulations open in the background causes the system to run out of virtual memory
Fixed! UE-61010 Editor crash when dragging Niagara Modules from one Emitter/System Stack to another
Fixed! UE-61037 ~10ms slow down when running with -game
Fixed! UE-60182 Button color does not change immediately when a material is applied
Fixed! UE-61287 Failing to launch on to Lumin device due to vulkan RHI issue
Fixed! UE-61204 ARCandidateImage and ARCandidateObject are missing Blueprint accessible APIs
Fixed! UE-60582 Mac: Daydream Instant Preview Encounters Handled Ensure On First VR Preview of Editor Run
Fixed! UE-61168 Crash when using remote live link publishing of face ar data and using xcode version < 10
Fixed! UE-60963 Failure to launch onto Magic Leap due to Shader Compiler issues
Fixed! UE-61148 Removal of bSupportAR causes the host to not start all the proper channels
Fixed! UE-61067 ARSkyLight defaults to having the lower hemisphere be black
Fixed! UE-60875 Lumin - Need to disable the “All_Phaedra_On…” Launch on option for 4.20
Fixed! UE-58385 FaceARSample - Looking for face to track prompt does not come up if tracking is lost while app is running
Fixed! UE-61207 nDisplay template icon does not fit well with other template icons

REMEMBER: Please report any new bugs you find by following the How To Report a Bug Guide

Hi, i’m newbie in ue4 and have no Mixed Reality Capture Framework C++ Classes in my content browser (plugin enabled) in UE4.20 Preview 4 and Preview 5 for MacOS. How can i fix this?

Is there a way to disable the display of the hdr panorama background in the Niagara editor ? I see there is a keybinding option, but it’s doesn’t do anything. Please add option to disable this and set the background color.

Finally, why did this take so long!?

It must be about the new action rpg example?

No, you now have to use potions inside the editor to access certain features. Like the potion of truesight that allows you to open the blueprint finder.

Is that one real or some kind of easter egg? Looking it up on the issue tracker comes up as unknown issue… Would be interested to see what it says.

Epic, can you guys make UE-60943 public?

I was joking obviously, @Zeblote was right, it’s more than likely that it relates to the upcoming action rpg content example.

Apologies if this has been discussed already somewhere, but has anyone looked into the new “Volume Texture” asset type? It seems like it should be pretty straightforward to use in that it takes in slices from a packed 2D texture, but so far all I’ve been able to do is make the editor crash immediately.

I’m also not sure how/when to actually sample from the 3D texture. I’d assume that it works with volumetric fog, and maybe some kind of ray marching tutorial, but other than that I’m not sure.

Good morning.
with the new release 4.20 preview 5 I can no longer create new Unreal Studio Product View projects because when I start my project, it tells me that it can not access a plugin
staticMeshEditorExtension failed to load …
in the attached two messages that appear to me. can I bypass the problem?
Thank you
Giorgio (GiDiO) D.E.

Is it allready on steam or not ?! Aswell people recomend me an website with wheels size calculator by the make of the car please?! i found that one Wheel & Tire Size Calculator – Tire Reviews witch is really great but to comapre?!

Following on from fix of UE-60969 (relative include path issue in build rules), I’m still getting failed plugin builds on preview 5.

I now get compilation failures with inability to locate #includes from engine module dependencies. If I have a module dependency specified and #include “File-name-only.h” for a header somewhere in the other module’s public folder, it fails. Seems that public include paths aren’t being propagated correctly.

Same problem… relative include fails… i have preview 3 though, so i’ll try to update on the launcher if it’s available there

Edit: Just tested with Preview5, it did throw me the warnings but it did compile, so maybe i’ll have to reset and re-check

Found a crash with HISM (Hierarchical Instanced Static Mesh) components used in native classes and expanded on Blueprints.
Added description and test files in answerhub. Filed a bug report as well.…-class-wi.html

Update: Found a workaround. Use only C++.
It seems the problem (and also a visual one in my other post) is related only to Blueprints. If the class using HISMCs is purely native, no crashes occur. But even the class’s children have to be native. Any Blueprint intervention and it crashes.

HISM components set to static mobility have lightmap sampling errors in edit mode after the Lightmass build. But on Play/Simulate they look like expected. Attached image demonstrates the issue.

I’ve reproduced it by adding an EmptyActor to the level with two HISM components and some instances added to them. Set the HISM components to Static and built the light.
I’ve also attached my system specs.

Edit: it seems to only happen on HISMCs inside Blueprints. Even if it is a blueprint that is a child of a native class and the native class instantiated the HISMC. But it’s not happening with purely native instantiated HISMCs.

I’m finding it very weird that no one seems to be bringing up anything about the HISM component. I’ve been having problems with it on 4.20 since I started testing it on preview 2. But only this week I’ve had the time to set up reproduction steps.

I’m really thrilled about this release. Been loving to work with Layered Materials, but in 4.19 you can’t reorder them and sometimes it takes more than 5 minutes to re-setup materials above a new inserted one that should go in the middle of the others. It’ll be very sad to have to stick to 4.19 because of HISM bugs. And I’m using them a lot. It’s a huge environment with several repeated pieces. Not to mention the new DoF that’s awesome for showing the work to your customer.

I’m also using HISMCs a lot, and actually, there’s a very horrible bug with HISMCs in both 4.19 and 4.20:

This is how it looks like when you call AddInstance in 4.18:

And this is 4.19 and 4.20:

So adding instances on runtime is completely broken visually if you have any wind in your level, the wind seems to get reset for all existing instances when new ones are added in 4.19 and 4.20.

This breaks my game unfortunately, so I very much hope it get’s fixed soon.

I’ve posted about it on the AH too: Very bad regression with AddInstance for HISMC in 4.19, wind gets reset for all existing instances - UE4 AnswerHub

How does the wind system work in Unreal? Is it animated by a time variable?