Unreal Engine 4.9 Preview


A Preview of the upcoming 4.9 release is now available via the Epic Games Launcher and . 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.

4.9 Preview Summary

This list provides a brief summary of updates in this release. Full release notes will be made available with the final 4.9 release. We may not be able to provide additional information about updates at this time.

  • Editor Updates:

  • You’re now able to use advanced search syntax when performing searches in the Content Browser

  • Improvements to the usability and robustness of Collections, including nested collections, dynamic collections, and more

  • Blueprint Updates:

  • Optimized Math Expression node is now more performant than regular nodes

  • Functions can now have Multiple Return Nodes

  • Construct Object From Class node lets you spawn baser object types

  • Get Class Defaults node gives access to Blueprints’ values without having to create an instance

  • Level Blueprints can now be communicated with via interfaces using the Get Streaming Level node

  • Asset ID and Class Asset ID are two new data types exposed to Blueprints

  • Core Updates:

  • Runtime Asset Cache is a generic asset cache system that can be used to persistently store data generated during runtime in configurable asset buckets

  • Framework Updates:

  • Sound Quality Levels give sound designers the ability to manage audio memory usage and some performance

  • Asynchronous Real-time Audio Decompression available on supported platforms

  • You can now define your own custom curve for attenuating sounds rather than simply being limited to the built in algorithms

  • You can now specify an interval at which a tick function will be executed

  • Improvements to Actor encroachment detection

  • The Montage Element Timing Interface helps you control the order that Montage events fire

  • We now support many different blending functions between animation poses and transitions

  • Hierarchical LOD improvements including preview builds and the HLODVolume

  • We support Metadata that can be added to animation assets now, derived from UAnimMetaData

  • Bone driven controllers allow you to adjust one or more components of a Driven bone based on the motion of a component of the Driver bone

  • Mobile Rendering Updates:

  • Dynamic Point Lights are now supported

  • Dynamic Character Shadows can be used with otherwise static lighting and shadowing

  • Decals are now supported

  • Platform Updates:

  • TADP replaced with NVIDIA AndroidWorks for Windows and Mac OSX

  • HTML5 SDK 1.30.0 is now included with the Engine distribution

  • Rendering Updates:

  • Improvements to Blendables, including Blueprint interaction via the Add or Update Blendable node

  • The Collision module on GPU particle emitters has a new property called ‘Collision Mode’ where you can specify ‘Distance Field’

  • Distance Field Ambient Occlusion quality and performance improvements

  • There are two new nodes to access the global distance field properties within the material editor

  • Area shadows for stationary lights

  • The new Ambient Occlusion Material Mask feature lets you access Lightmass calculated AO in your material

  • VR Updates:

  • Motion Controller devices like the Vive SteamVR Controller, the Sony Move, and others will now all be available through a common interface

  • Major SteamVR Updates

  • Additional details and bug fixes will be communicated in the full Release Notes for 4.9!

Quick Notes:

  • UE 4.9 Preview does not yet support Visual 2015. It is expected to be experimental via for the final 4.9.0 release. For additional information, please view this thread.
  • UE 4.9 is expected to run on Windows 10, but has not been thoroughly tested.
  • DX12 is still very experimental with 4.9, but it can be enabled by running the editor with the -D3D12 parameter on Win 10.
  • UE 4.9 does not support the OS X 10.11 El Capitan beta

Known Issues List

This is a list of recently discovered bugs in our 4.9 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 4.9 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 for 4.9 Preview 4

UE-19709 No mouse interaction with 3d viewport over RDP
UE-19919 IOS doesn’t build against latest IOS 9 SDK
UE-19042 Changing HISMC ‘Collision Profile’ in BP class does not always propagate to BP instances
UE-19166 RestartLevel command causes a crash in VR
UE-18762 ChildActor Component with physics spawns at the wrong location
UE-18482 Various engine materials fail to compile due to too many texture coordinate sets in use
UE-19528 Custom Enums break blueprints on hot reload
UE-19487 All GetResourceSize methods need to be audited for proper behavior when Exclusive mode is passed in
UE-19394 Post Processing Does Not Account For Screen-Percentage Quantization
UE-19837 Crash when HotReload UMGEditor
UE-19828 PS4 Directory Iteration doesn’t work properly in some cases
UE-19707 Navigation System is gathering navigation bounds too early
UE-17160 Guid in use warning when recompiling Blueprint
UE-16073 Adding a cube component in the Blueprint editor results in a mesh with the default material in the preview.
UE-15593 Calling a parents function that is used in a child blueprint from a spawn actor from class node that is being called back in the parent will cause an error
UE-19570 Renamed HLOD map disappears when selects don’t save
UE-17748 Cooked packages contain asset registry information
UE-19632 Static meshes are not cooking deterministicaly
UE-19938 Deploying to device, changing MobileHDR and re-deploying gives shader compile error on device
UE-19890 attachTo should use teleport = true
UE-20084 Leaderboard integer read always fails on Android
UE-19747 Adding a StaticMeshComponent pointer to a derived StaticMeshComponent class has inconsistent behavior
UE-19266 A C++ project with the name, “GearVR”, will not build
UE-20077 Multiple apply prompts on dirty material once editor is closed
UE-20080 Unable to generate SSH key with DeltaCopy in default location and unspecified
UE-20083 Mac client crashes when mousing over an unbuilt class building.
UE-20024 SideScroller2D sample crashes when opening on an Iconia Tab
UE-20040 Distribution builds on Android with AndroidWorks have debug symbols on libgnustl_shared.so
UE-19961 ElementalDemo locks up on the 8800 Ultra
UE-19952 6 blueprint errors when cooking ContentExamples
UE-20005 Unable to Edit Curve Names between 2 Different Animsets (if name of curve is the same)
UE-19959 Anim Time Ratio Doesn’t Factor In Pin Sequence
UE-20079 Crash Typing Special Characters using US-International-PC keyboard in MacOS:10.10.4
UE-20019 Input Bindings losing rename information after re-opening project
UE-19827 ContentExamples BP_DemoRoom asset shows major artifacting when launched
UE-19866 UE4 logo splash doesn’t appear on some iOS devices
UE-19839 Content Examples Space Shooter mini game does not start
UE-19847 ContentExamples No PlayerStart in particles_intro map
UE-19885 ContentExamples PhysicalAnimation hit reaction example does not react
UE-19875 Launch On: No graceful warning given when an iOS device isn’t found on provision
UE-19871 Swing Ninja crash loading level on some iOS devices
UE-19906 Partcle Effects sample displaying Default Textures
UE-19905 KiteDemo only renders boy and Kite in PIE or standalone
UE-19915 RealisticRendering M_CoffeeRings has the wrong color
UE-19946 Inputs and Outputs missing in Details pane on Interface function that has been transferred to local function
UE-20022 Infinite Script Recursion error crashes editor and produces UnrealScript errors in
UE-19989 Particles are not appearing in mobile previewer/HTML5
UE-19899 3D widget in ContentExamples does not appear in Standalone Game
UE-19944 Pressing “X” to clear text field results in closing window instead.
UE-20071 interaction with 3D widgets are not possible when moving the pivot point
UE-19907 “Create Save Game Object” node does not throw an error on compile when no class is selected
UE-20020 Same-named variables of other classes listed as references in blueprint
UE-19995 Animation Preview not playing under certain conditions
UE-20069 Interrupting SetViewTargetWithBlend causes camera to snap to one actor
UE-19924 Print String does not print to the viewport screen from the Construction Script
UE-19701 fails during cook command
UE-19627 : When returning from lock or home, application becomes unresponsive, no menu - or chicken is tilted with incorrect menu
UE-19703 Deployed code projects crash when closing
UE-19604 Mac executable is not created with Copy to Device using a blueprint project
UE-19514 Editor crashes when deleting recently restored nav mesh bounds volume
UE-19673 The DemoRec console command crashes the editor if used during PIE
UE-19860 PBO Disable option does not work in Hide Bone By Name node
UE-19954 Additive anim slot takes over when played with Matinee
UE-19861 Morph Target Normals not importing as expected when Normals are locked
UE-19953 Camera Information across two Matinee Data groups do not persist from one to the other.
UE-19404 Misbehavior plugging lollipop android in to gearVR with project launched
UE-19361 StrategyGame minimap has very bright colors on the Galaxy S6
UE-19344 iOS: Sound stops playing in strategy game
UE-19462 Dedicated Server ammo pickups do not disappear for other clients
UE-19545 Implementing an interface in a blueprint does not show interface functions until interface is opened and compiled
UE-19855 Tick delta time does not provide the time between ticks (as stated in documentation)
UE-19291 Mobile Preview crashes once all the shaders are compiled
UE-19286 On Mac, cannot delete Blueprint elements via the Delete key
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-19677 AddProceduralMeshComponent node throws UnknownTemplateReferenced errors in duplicated Function
UE-19743 Using HideCategories specifier does not hide custom categories
UE-19999 Instanced subobjects are not always instantiated as expected.
UE-19413 Previewing Notification on Material Nodes never leaves when Previewing stops
UE-19584 Activating physics on a component will break movement for the component
UE-19823 Reimporting Meshes after renamed in Engine or Modeling Program break reimporting
UE-19737 Ctrl + Enter during PIE closes the console and then the console can no longer be reopened during that PIE session
UE-19831 SphereGradient3D Material Function has unconnected (or unnecessary) Scene Depth Call
UE-19917 Collision of child component doesn’t rotate if the parent is simulating physics
UE-19931 A Blueprint created from Actors in the level does not preserve the relationship (hierarchy and transforms) of both components
UE-19988 Mouse offset when switching resolution between windowed mode / fullscreen
UE-20029 Instanced meshes do not accurately use volume light samples when lit in a statically lit scene
UE-20044 The Select node always calculates all inputs
UE-20033 ESplineMeshAxis Enum is not available as a variable or struct
UE-19991 Preview Meshes in Material Instances lose their association to material on close.
UE-19252 Setting Physics Blend Weight to anything between 0 and 1 causes erratic behavior
UE-19241 In Mac crash reporter client, the “click here to view directory” link does nothing
UE-19533 The “IsHeadMountedDisplayEnabled” node always returns true if an oculus was detected when the project is opened
UE-19541 Typo in description of SkySphere Horizon Falloff
UE-19163 Editing duplicated instanced sub-objects also edits other sub-objects
UE-19080 Templates - Vehicle Advanced - Title text actor is sunken into ground mesh and is not visible
UE-19086 GDC2014 PIE Error Transmission Audio accessed none from node Fade Out
UE-19075 Crash in editor when launching blank bp and basic code template
UE-19037 Vehicle Advanced BP and Vehicle BP templates do not have mobile joysticks
UE-19062 Re-parenting blueprint actors do not lose interfaces associated with their previous parent blueprint
UE-18953 Side Scroller code player position is not centered on ledge
UE-18977 Animation blueprint does not always update properly after compile
UE-18867 The walls on each side of Paper2D use the incorrect sprite
UE-18815 First Person gun has odd rotation
UE-18821 can see player characters shoulder in First Person
UE-18785 Could not parse error: UE4 Releases: ShooterGame_Client_Win32_Client_Test_MakeBuild Package Failure
UE-18820 Linux build failing Build Products cannot be found for node ToolsForCompile_OnLinux
UE-18779 MAC: Playback of duplicate movie results in black screen on second play
UE-18477 Drag and dropping a pin on one of multiple return nodes does not add pin to each
UE-19253 Blueprint derived from C++ class not saving correctly
UE-18945 Steering Curve property does not affect steering
UE-19212 MultiplayerShootout Main Menu Bug
UE-19690 [CrashReport] UE4Editor_CoreUObject!UObjectBase::IsValidLowLevelFast() [uobjectbase.cpp:251]
UE-19616 Distance Field shadow culling when view is at certain angles
UE-19818 Static light reflections do not honor Min Roughness settings for lights.
UE-19445 Entire mac locks up first time editor calls Finder import window for 10-20 seconds
UE-18240 Landscape widget does not work when viewport has realtime disabled
UE-17969 Bad shadows on boy as he enters the cave on AMD R 290
UE-17898 Crash occurred (only on Mac) for FSkeletalMeshObjectGPUSkin
UE-18430 Compiler error on indirect blueprint component references when change is made to actorcomponent
UE-18618 Ensure triggered by level blueprint when Play as Listen Server is set
UE-18504 Console window is locked when casting to the player controller
UE-18314 Copying more than 1 socket between skeletal meshes retains only one socket name
UE-18071 Clients fail to load in Standalone mode with 2 players while Use Single Process is disabled
UE-17353 Crash occured selecting re-center in Reference Viewer
UE-16307 Sphere Mask using Absolute World Position not rendering in ES2 (Android or iOS)
UE-16534 Adjusting transform of a mesh with LODs causes LODs to flicker
UE-15281 Hot Reload from Xcode to Editor not working on Mavericks
UE-17227 [CrashReport] UE4Editor_Engine!DoReadTaskResults() [shadercompiler.cpp:147]
UE-19590 Cascade Curve Editor Workflow Issues
UE-19606 Get Functions are not Available for Particle Systems via Blueprints
UE-19591 Min and Values in Cascade Distributions are inconsistent in order
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-18081 RepNotify variables passed by reference to a function or macro that then change the value of the variable do not trigger the OnRep function on the Server
UE-16299 Reflection Vector not translating into ES2 when applied via an Emissive Color
UE-15637 Editor crashes with 2 or more Clients when spawning in a Blueprint created from a Static Mesh using the Blueprint/Add Script button
UE-15499 Delegation issue with copied instances of a Trigger BP that is based off of the StaticMeshActor
UE-11876 OnRep functions do not fire on the client
UE-18906 [CrashReport] Crash in !UE4Editor_D3D11RHI!FD3D11DynamicRHI::Shutdown()

That’s cool!!!Thanks a lot~

Yay, Awesome!

That was fast! :smiley: I hope this version runs better than 4.8 did for me! :smiley:

Reading each update is like opening a gift in Christmas.

Do you speeded in this update for mobile !!!

@ Punctuation marks aren’t pack animals :rolleyes:

Thanks for this preview! Will try it as soon as possible. Your download servers are a bit overloaded, I only get 1.6 MB/s.


I see you have included CodeLite IDE support. I also heard @yaakuro added support for all platforms.

Will you guys let us use it on Windows or Linux only? Please include it in Windows binary.

I hope directx12 is gonna be integrated in the full release of 4.9 ! That would be awesome.

Will support visual 2015 ?

What are Unreal Engine 4’s system requirements?
Will support Windows 10 64-bit?

I’m really happy to see that audio is finally getting some love.

Im hopeful the android build issues will be fixed with the death of TADP from the engine, although it says in known issues “Android Build Issues” lol

There are a few Android/mobile features as well I saw poking around

  • Recover Purchase node
  • Disable the android/back button option

this is cool

[=Aabs Inc.;342801]
What are Unreal Engine 4’s system requirements?
Will support Windows 10 64-bit?

I’ve been using 4.9 with windows 10 preview for over a month now and it works like a charm! So i see no reason why 4.9 preview 1 wont work with official win 10.

I’m most excited for “Functions can now have Multiple Return Nodes” on your list!

That said, I hope you guys consider allowing interface functions to be marked as pure, or for interface input functions to mark parameters as passed by reference!

Where is the parameter for thistrello.com/c/jxYdAb9F/518-first-person-weapon-optionally-rendered-with-a-different-fov-than-the-scene-done-4-9 ?
*The feature pack rolling is broken.

So, a few things I noticed in 4.9:

  • Some materials stay gray. They compile correctly, but once applied on a mesh they just stay with the gray default material.
  • The spawn Actor node now uses a different way to define collision, which breaks current behavior. I before mostly used “Spawn even if colliding true” but now all the nodes were updated to the default value of “Try to adjust location, don’t spawn if still colliding”. This needs to change since it breaks all the Spawn Actor nodes!
  • After I open the project I get this:


Seems to have no impact in the game.