Unreal Engine 4.10 Preview


A Preview of the upcoming 4.10 release is now available via the Epic Games Launcher and GitHub. We have made this Preview available so that our developer-community can help us catch issues before the final release. As fixes are implemented, we will release updated previews throughout the development cycle. Please be aware that the preview releases are not fully quality tested, that they are still under heavy active development, and that they should be considered as unstable until the final release. Developers should not convert their projects for active development on preview releases. Please test on copies of your project instead.

We encourage users to check out the preview to try new features and inform us of any issues which we may not have caught. A Known Issues List is provided below which will be updated periodically. If you discover any additional issues with this preview release, please report the issue on the Bug Reports section of the Unreal Engine AnswerHub.

4.10 is a smaller release than previous releases. We focused less on new features, and more on bug fixes. Our goal is for 4.10 to prove to be a very stable release for everyone to develop on.

4.10 Preview Summary

This list provides a brief summary of updates in this release. Full release notes will be made available with the final 4.10 release. We may not be able to provide additional information about updates at this time.

  • Build Updates:

    • The launcher distribution of the engine now requires Visual Studio 2015 for code projects. Visual Studio 2013 and 2015 are both supported on GitHub.

  • Platform Updates:

    • Multiple gamepads are now supported for Android along with identifying some common controller types and mappings.

    • Support for an optional launch screen for Android projects has been added.

    • Xcode Project Overhaul. Instead of a single project containing multiple targets we now have a workspace consisting of multiple projects, one per target.

    • SDK upgrades: Visual Studio 2015, Xcode 7, iOS9/MacOS 10.11 El Capitan, PS4 SDK 3.00, Android Marshmallow/6.0

    • Users are now able to explicitly select a mobile provision and certificate in the iOS Project Settings.

  • Mobile Rendering Updates:

    • Refraction on Mobile enabled on iPhone 5S and above and Android_High

    • Material Quality Level Scalability System for Mobile. Allow your mobile game to scale all the way down to low end devices, without sacrificing quality!

  • VR Updates:

    • In order to optimize rendering for head mounted displays, we’ve implemented Hidden and Visible Mesh optimizations. These two optimizations ensure that we do not spend GPU time working on pixels that will not be displayed in the actual device, because of lens distortions.

    • We’ve updated Motion Controller Components to now do a late-update right before we begin rendering. That means that controls will feel more responsive, and better reflect what the player is doing in the real world.

  • Landscape Updates:

    • Landscape Mirror Tool. Easily make symmetrical landscapes!

  • Editor Updates:

    • Blueprint Node Alignment Routines. A comprehensive set of layout routines for fast organization of blueprint graphs.

    • An experimental state for Sequencer (the future replacement for Matinee).

      • To enable Sequencer, go to Edit > Plugins > Editor > Level Sequence Editor. Create Level Sequence assets under the Animation menu.

  • Additional details and bug fixes will be communicated in the full Release Notes for 4.10!

More than 300 bug fixes have been included in this Preview, and additional fixes will be added leading up to the final 4.10 release.

Known Issues List

This is a list of recently discovered bugs in our 4.10 Preview engine release that includes high priority bugs discovered by Epic, as well as all confirmed community-reported bugs. We will attempt to resolve critical bugs before the final 4.10 release, other bugs that do not block development or have workarounds may be marked to be fixed in one of the future hotfixes or major releases.

Please be aware that this is not a comprehensive list of all engine bugs, it is simply a snapshot of some of the latest bugs discovered with this preview release. This list will be periodically updated with new additions and to reflect which ones have been fixed internally, so be sure to check back!

Known Issues in 4.10 Preview 4 - CL 2749536

UE-22844 More Fixes for analytics event for abnormal editor termination
UE-22838 Revert 2738109 as it is causing as many problems as it fixes
UE-22820 Engine crashing on stopping PIE when AI is using BT Simple Parallel
UE-22628 Hot reload fails when project name doesn’t match target name
UE-22550 Toggling MobileHDR and then using Launch On Android crashes compiling shaders
UE-21958 Slate/UMG: Update Checkbox, Slider, ComboBox to work with controller
UE-21948 Create Plugin DRM API Stub
UE-18047 UEdGraphNode’s NodeWidget ptr is unsafe
UE-21305 Distance field shadows cull objects in front of the near plane incorrectly
UE-21304 Distance field shadows not working on AMD code workaround
UE-21240 Duplicating an instanced sub-object property and proceeding to undo, compile, redo will crash
UE-19837 Crash when HotReload UMGEditor
UE-20604 Code signing Mac when a windows host cooks and paks
UE-22599 Vehicle Advanced - Gear and Speed missing in Third Person View
UE-22539 ContentExamples Particles_Intro is too dark on Mac
UE-22703 Specifying a custom UMovementComponent class via SetDefaultSubobjectClass() does not seem to serialize default value edits correctly on the CDO.
UE-22442 Find-in-Blueprints fails to collect implemented interface graphs
UE-22852 Node comment bubbles no longer appear in editors (BP, material)
UE-22859 Editor crashes on hot reload for something that isn’t reinstanced
UE-22812 Forward Rendering Override ‘High’ setting not affecting Android or editor preview modes
UE-22810 Switching between Android and iOS Rendering Preview doesn’t respect FR Overrides
UE-22731 Crash undoing the redo of deleting a bp instance with edits after modifying class
UE-22732 Components added to instance lose transform on undo if deleted and class edited
UE-22726 First Person templates have various can’t find file warnings when cooking
UE-22738 SunTemple crash during first launch on iPad 4
UE-22851 Running Automation Test for Directory Watcher Causes the Editor to Crash
UE-22880 FullScreen Immersive on KitKat and above devices still shows device buttons
UE-22840 UMG animation timeline runs the length of the visible timeline when previewing animation
UE-22778 Detour AI Controller Not Functioning Properly
UE-22673 ContentExamples Blueprint_Input_Examples enemy ship does not spawn
UE-22632 Building the Engine using Visual Studio 2015 can fail if Windows Driver Kit is installed.
UE-22631 ContentExamples - Blueprint_Communication and Blueprint_HUD crash in standalone game
UE-22636 ContentExamples - Effects Map Lighting Needs to be Rebuilt
UE-22626 StrategyGame - Mini map and health bars not visible in launch on
UE-22512 ClassAssetID’s within a struct do not maintain their default value when reopening the struct
UE-22471 Crash when attempting to PIE after undoing deletion of a component
UE-22459 Failing to compile Code project in Binary build (‘HeadMountedDisplayCommon.h’)
UE-22498 Startfpschart is not capturing avg GPU time on some Macs
UE-22455 SunTemple landscape has rendering artifacts on low end devices
UE-22418 Sky sphere is flickering blue in default level using OSX Mavericks
UE-22406 Reflections not displaying properly in OSX Mavericks
UE-22391 Particles are not showing up in P.I.E.
UE-22540 IK collision causing jittering on cloth in Content Examples map
UE-22522 Content Examples - 6.1 self shadow object not working properly
UE-22519 LandscapeMountains trees disappear as you get closer
UE-22432 Strategy Game base upgrades spawn on top of each other
UE-22347 GDC2014 (FeaturesTour2014) Load Errors for Failed to Import Assets
UE-22537 ContentExamples Post Process Blendables shows incorrect effect
UE-22422 Projects are crashing on the iPhone 6
UE-22616 Cannot Create a New Project if Windows Username Contains a Special Character
UE-22602 Using Fixed Frame Rate Increases the Speed of Auto Save
UE-22118 Renaming component causes Engine/Transient save error
UE-22206 Xbox One: Controller reconnect prompt displays “Cross Button”
UE-22204 Xbox One: Some particles in Elemental demo are missing
UE-22202 DoF Focal Distance and Region not respected in Mobile/Metal Preview or Deployment
UE-22199 UFE package shipping HTML5 hangs at Launching UAT
UE-22166 HTML5 Cook on the fly will launch and then close browser
UE-22165 UFE cook on the fly (shipping config) fails to load descriptor file on game launch
UE-22381 Deleting a Struct Attached to a Variable in a Blueprint Prevents it from Compiling
UE-22523 Translucent Surface Material and Additive Particles not rendering on Metal in Shipping/Distribution
UE-22074 Editor crashes upon opening with -opengl3
UE-22066 Side Scroller 2D example map could not be found warning
UE-22119 Multiprocess Cooking on Mac hangs during Cook content
UE-22518 Asset Override Editor does not have vertical scrollbar until window is resized
UE-22367 Transparency for Widget components is not working on iOS devices
UE-20526 Crash swapping to Morpheus VR screen from PC game
UE-21961 Surfaces in firefox are reflective when launching from Mac
UE-21975 Crashes on the SHIELD do not produce callstacks
UE-21899 Failure to load libeay32.dll causes crash when opening EngineQATest project in 4.10 Binary
UE-21700 BP_Spline_Location still using depreciated functions in Content Examples project
UE-22782 Reimport does not respect the Combined Mesh Checkbox
UE-22874 Adding Text Render Component at Runtime Crashes Standalone
UE-22876 Sidescroller Character Gets Stuck on Platform Edges When Moving on Tick
UE-22878 Behavior Trees cannot be saved if the Blackboard assigned to it was opened before opening the Behavior Tree from the Content Browser
UE-22623 Hidden In Game option for Layers in TileMap Editor not working
UE-22897 Opening a DataTable that is set to a Struct that is using a Key variable will crash the editor
UE-22696 Crash on importing specific Skeletal FBX exported with FBX2016
UE-22245 Editor Crashes When a Component and Actor Implement Two Interfaces
UE-22192 Compressed cooked packages feature is not functioning correctly.
UE-22183 Duplicated Blueprint Causes Incorrect Target for Events
UE-22435 Creating a Data Table Using a Struct with a Slate Brush Variable Causes the Editor to Crash
UE-22373 Rapidly Undoing in Animation Blueprint Causes the Editor to Crash
UE-22311 Weight Layers and Alpha Layers on Material create Black areas when Painted on a Landscape
UE-22839 Custom Component Being Added to Wrong Target Blueprint
UE-22845 Trigger Volume Blocks First-Person Template Projectile
UE-22462 Naming an Event Dispatcher the Same as an Overridable Function Corrupts the Event Dispatcher
UE-22271 SetMasterPoseComponent overrides any SetMorphTarget operations
UE-22214 Crash when viewing Lightmap Density mode and with Vert
UE-22207 Zipping up projects with / creates folders to nest the zip in
UE-22205 Reimporting a static mesh will reset multiple properties in the Static Mesh Editor
UE-22193 Using the down arrow key in the Toolbar’s Blueprints > Open Blueprint Class sub-menu will immediately open the first Blueprint listed
UE-22622 Zooming in or out and then quickly panning to the left or right causes the camera to snap back to original position.
UE-22607 Procedural Sounds Dropping First Samples
UE-22344 Opacity is not receiving Input for Material Functions
UE-22707 Ribbon Type Particles will not follow Local Space Particles when assigned as Source
UE-22777 Adding widget to viewport on code overlap event causes the editor to crash when opening child blueprint
UE-22842 Blueprint Doesn’t Show Components Added at Runtime
UE-22847 Attempting to hide “CharacterMovement” in a custom character class breaks Details panel inside derived blueprint
UE-21424 Console renders incorrectly on SteamVR / HtcVive
UE-21644 Setting Collision Enabled with the option for No Collision on a Destrucitble after it has fractured will cause a crash
UE-21300 SetActorLocation does not affect WheeledVehicles
UE-20920 Adjusting Agent Radius in RecastNavMesh causes AI to not move
UE-20791 Building Lighting Hangs at 50% in an Empty Level
UE-22659 [CrashReport] UE4Editor_D3D11RHI!VerifyD3D11CreateTextureResult() [d3d11util.cpp:239]
UE-20606 Interface function has the incorrect pin type if referencing self
UE-20757 [CrashReport] UE4Editor_UMG!SWorldWidgetScreenLayer::RemoveComponent() [widgetcomponent.cpp:114]
UE-20601 Crash when Blutility saved asset deleted and restored in a level
UE-22702 Using the Auto-Convex Collision option on Mac causes Crash
UE-19673 The DemoRec console command crashes the editor if used during PIE
UE-21346 [CrashReport] DistanceField Crash while running Size Map on Content Folder
UE-20155 Clearcoat shader disappears if any asset using the Material leaves lighting
UE-19677 AddProceduralMeshComponent node throws UnknownTemplateReferenced errors in duplicated Function
UE-19999 Instanced subobjects are not always instantiated as expected.
UE-19579 If an ensure() fails within an automated test, the test can still show a positive result.
UE-20750 Opening a level in PIE after adding a variable to a struct referenced in the GameInstance crashes this project
UE-19397 Camera Shake Oscillation Duration no longer accepts -1 as indefinite
UE-19929 Creating a Blueprint out of existing Blueprints removes all assigned Static Meshes from components
UE-21408 Derived Data Cache is included but not used in Kite Demo
UE-22457 Static Lighting from a nested Blueprint is not saved in Lighting Build
UE-22483 Material Names on Import do not match SkinXX Order
UE-22337 Nested UPROPERTY components show as direct children of the parent object
UE-19599 Copying a Static Mesh actor from the level and pasting it into a Blueprint as a component does not retain any of the values of the copied actor
UE-11876 OnRep functions do not fire on the client
UE-22849 Get key node is no longer available within the On Analog value change override

REMEMBER: Please report any new bugs you find to the UE4 Answerhub

That’s a great news !

Did you meant 4.10 ?

EDIT: sorry Chosker, i was faster :smiley:

I guess you meant 4.10 :stuck_out_tongue: :stuck_out_tongue: :stuck_out_tongue:

I’m glad to hear this one’s focus was on bugs and stability.
I can only hope you guys have spent some time “completing” the feature set (i.e. all those cases of feature A and feature B not working together, and all those cases of feature X only working on specific scenarios)

As a mobile indie game developer, this is much a surprise and a delight! :cool:

I did indeed. Edited, thanks.

Thanks for your greate work!
I’m a little curious about will the gpu particles be available in ios metal in 4.10?Since it has been postponed from 4.7…

What happened to the Blueprint optimizations to bring it to C++ levels? (Or BP to C++ converter)

In active development – most likely not going to make it till 4.12 though.

This looks great. Can’t wait for the official release. However, Child Actor can’t be hidden/unhidden is really annoying thing. Will it be fixed or you have a work around it?

Ah darn… /sadface about the delay (since it was brought up on a stream weeks ago that it would be in 4.10). Thanks for the update, keep up the great work everyone.

Well makes the launcher completely useless for me, once again. Back to GitHub distributions it is then.

Why are “more than 300 fixes” being implemented into a “major” release? Should these “fixes” be included in the 4.8 or 4.9 minor patches? It is the one thing I have never understood about the release management / versioning of the Unreal Engine.

as these threads often become fast Q and A I’ll go with the flow…

are there plans to allow Multiple PhysicalMaterials per object (coming from the material) ?, i.e. for procedural landscape materials and other large’ish ‘composite’ objects

Any chance we’ll see more of Niagara this version?

I very much second both of these and add some more on top: Will we (either 4.10 or even ever) see support for smooth SpeedTree LOD transitions? Additionally, can we get a scale min / max property on landscape grass?

Awesome, I’ve been waiting for the visual studio 2015 move.

Thanks for the great work!

When building for Android/GearVR, i get the following error. Android SDK was updated to the latest version with the SDK manager.

MainFrameActions: Packaging (Android (ETC2)): UnrealBuildTool: BUILD FAILED
MainFrameActions: Packaging (Android (ETC2)): UnrealBuildTool: D:\NVPACK\android-sdk-windows	ools\ant\build.xml:716: The following error occurred while executing this line:
MainFrameActions: Packaging (Android (ETC2)): UnrealBuildTool: D:\NVPACK\android-sdk-windows	ools\ant\build.xml:730: Compile failed; see the compiler error output for details.
MainFrameActions: Packaging (Android (ETC2)): UnrealBuildTool: 
MainFrameActions: Packaging (Android (ETC2)): UnrealBuildTool: Total time: 6 seconds
MainFrameActions: Packaging (Android (ETC2)): UnrealBuildTool: UnrealBuildTool Exception: ERROR: cmd.exe failed with args /c "D:/NVPACK/apache-ant-1.8.2/bin/ant.bat" debug
MainFrameActions: Packaging (Android (ETC2)): CommandUtils.Run: Run: Took 82,0144055s to run UnrealBuildTool.exe, ExitCode=5
MainFrameActions: Packaging (Android (ETC2)): BuildCommand.Execute: ERROR: BUILD FAILED
MainFrameActions: Packaging (Android (ETC2)): Program.Main: ERROR: AutomationTool terminated with exception:
MainFrameActions: Packaging (Android (ETC2)): Program.Main: ERROR: Exception in AutomationUtils.Automation: Command failed (Result:5): D:\Development\UE4\Unreal Engine\4.10\Engine\Binaries\DotNET\UnrealBuildTool.exe GearVRGame Android Development  "D:\Development\Neuer Ordner\GearVRGame\GearVRGame.uproject"  -noxge -rocket -NoHotReloadFromIDE -ignorejunk. See logfile for details: 'UnrealBuildTool-2015.10.14-19.07.48.txt' 
MainFrameActions: Packaging (Android (ETC2)): Stacktrace:    bei AutomationTool.CommandUtils.RunAndLog(String App, String CommandLine, String Logfile, Int32 MaxSuccessCode, String Input, ERunOptions Options, Dictionary`2 EnvVars)
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.CommandUtils.RunUBT(CommandEnvironment Env, String UBTExecutable, String CommandLine, String LogName, Dictionary`2 EnvVars)
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.UE4Build.BuildWithUBT(String ProjectName, String TargetName, UnrealTargetPlatform TargetPlatform, String Config, String UprojectPath, Boolean ForceMonolithic, Boolean ForceNonUnity, Boolean ForceDebugInfo, Boolean ForceFlushMac, Boolean DisableXGE, String InAddArgs, Boolean ForceUnity, Di
MainFrameActions: Packaging (Android (ETC2)): ctionary`2 EnvVars)
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.UE4Build.Build(BuildAgenda Agenda, Nullable`1 InDeleteBuildProducts, Boolean InUpdateVersionFiles, Boolean InForceNoXGE, Boolean InUseParallelExecutor, Boolean InForceNonUnity, Boolean InForceUnity, Boolean InShowProgress, Dictionary`2 PlatformEnvVars)
MainFrameActions: Packaging (Android (ETC2)):    bei Project.Build(BuildCommand Command, ProjectParams Params, Int32 WorkingCL)
MainFrameActions: Packaging (Android (ETC2)):    bei BuildCookRun.DoBuildCookRun(ProjectParams Params)
MainFrameActions: Packaging (Android (ETC2)):    bei BuildCommand.Execute()
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.Automation.Execute(List`1 CommandsToExecute, CaselessDictionary`1 Commands)
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.Automation.Process(String] CommandLine)
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.Program.MainProc(Object Param)
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.InternalUtils.RunSingleInstance(Action`1 Main, Object Param)
MainFrameActions: Packaging (Android (ETC2)):    bei AutomationTool.Program.Main()
MainFrameActions: Packaging (Android (ETC2)): ProcessManager.KillAll: Trying to kill 0 spawned processes.
MainFrameActions: Packaging (Android (ETC2)): Program.Main: AutomationTool exiting with ExitCode=5
MainFrameActions: Packaging (Android (ETC2)): Domain_ProcessExit
MainFrameActions: Packaging (Android (ETC2)): copying UAT log files...
MainFrameActions: Packaging (Android (ETC2)): RunUAT.bat ERROR: AutomationTool was unable to run successfully.
MainFrameActions: Packaging (Android (ETC2)): BUILD FAILED
PackagingResults:Error: Error Unknown Error

Sequencer preview? I’m there!

While attempting to build a level with landscape in 4.10 with the 3rd person blueprint template, I got this message

UnrealLightmass.exe - system error
The program can’t start because VCRUNTIME140.dll is missing from your computer. Try reinstalling the program to fix this problem.


Please submit an AnswerHub with the full logs attached as a .txt file and we will be more than happy to assist you further with this build failure.