Unreal Engine 4.26 Preview

[EXpMiNi]

GPU Lightmass test :

Emissive surfaces work perfectly fine on movable objects but lights do not.
Changing emissive inside Material Instances do no refresh GPU Bake and it could be nice to have an option to disable emissive GPU baking per object as well (it wasn’t working on CPU, having the option to disable it or not could be a good idea).

[MostHost_LA]

Keep getting a near constant crash due to chaos

Assertion failed: Im > 1.175494351e-38F [File:D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Public\Chaos\Utilities.h] [Line: 297]

UE4Editor_Core!AssertFailedImplV() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Misc\AssertionMacros.cpp:102]
UE4Editor_Core!FDebug::CheckVerifyFailedImpl() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Misc\AssertionMacros.cpp:458]
UE4Editor_Chaos!Chaos::Utilities::ComputeJointFactorMatrix<float>() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Public\Chaos\Utilities.h:297]
UE4Editor_Chaos!Chaos::FJointSolverGaussSeidel::ApplyPointProjection() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Private\Chaos\Joint\PBDJointSolverGaussSeidel.cpp:1764]
UE4Editor_Chaos!Chaos::FJointSolverGaussSeidel::ApplyProjections() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Private\Chaos\Joint\PBDJointSolverGaussSeidel.cpp:250]
UE4Editor_Chaos!Chaos::FPBDJointConstraints::ApplyPushOutSingle() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Private\Chaos\PBDJointConstraints.cpp:1341]
UE4Editor_Chaos!Chaos::FPBDJointConstraints::ApplyPushOut() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Private\Chaos\PBDJointConstraints.cpp:953]
UE4Editor_Chaos!Chaos::TPBDConstraintIslandRule<Chaos::FPBDJointConstraints>::ApplyPushOut() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Public\Chaos\PBDConstraintRule.h:240]
UE4Editor_Chaos!Chaos::TPBDRigidsEvolutionBase<Chaos::FRewindableEvolutionTraits>::ApplyPushOut() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Public\Chaos\PBDRigidsEvolution.h:727]
UE4Editor_Chaos!<lambda_0fff0a27e9ae33a31caeec5a000bd76b>::operator()() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Experimental\Chaos\Private\Chaos\PBDRigidsEvolutionGBF.cpp:404]
UE4Editor_Chaos!ParallelForImpl::TParallelForData<TFunctionRef<void __cdecl(int)> >::Process() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Async\ParallelFor.h:177]
UE4Editor_Chaos!TGraphTask<ParallelForImpl::TParallelForTask<TFunctionRef<void __cdecl(int)> > >::ExecuteTask() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Async\TaskGraphInterfaces.h:886]
UE4Editor_Core!FTaskThreadAnyThread::ProcessTasks() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:1065]
UE4Editor_Core!FTaskThreadAnyThread::ProcessTasksUntilQuit() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:888]
UE4Editor_Core!FTaskThreadAnyThread::Run() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:965]
UE4Editor_Core!FRunnableThreadWin::Run() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Windows\WindowsRunnableThread.cpp:86]

If you want to test it you can probably convert DynoFoliage to .26

DynoFoliage in Blueprints - UE Marketplace

The phat assets also need adjusting for chaos currently. That’s expected until we have parity anyway. the crash is not however.

[Chosker]

@KristofMorva

I think it might also be fixed in the next preview: https://github.com/EpicGames/UnrealE…6bf9006bfef87e

thanks for this info!
I compiled the 4.26 branch on GitHub and I can confirm the new Experimental Water Plugin is there

[Nguyen_Bui]

When they gonna update the UI. It stuck from 2000 not 2020 -.- seriously So ugly to look at

[AyemFyr]

Could you guys maybe make next preview version slightly more stable? Getting constant crashes when recompiling character blueprint with animation graph open. So far my experience with 4.26 is mostly finding new unexpected ways to get a crash.

[freaknbigpanda]

@Tim_Hobson

Enable the Groom and Alembic Groom Importer plugins. Then, import or open an existing Groom Asset from the Content Browser. You’ll get the new Groom Asset Editor that way.

Thank you for that!

The typical workflow described here requires that the user import every interpolated hair as a nurb curve and then some number of them are automatically considered guide curves. I was wondering if there is a way to only import guide curves and then get unreal to do the interpolation of the hairs itself? The xgen groom I am working with has literally millions of strands and trying to generate nurbs curves in maya for every strand crashes my computer since it eats over 60GB of ram/virtual memory. It would be easier for me if I could just import the guides and have unreal engine do the hair strand interpolation instead. Otherwise I will probably try to break the groom up into smaller chunks and import it that way.

[freaknbigpanda]

@Aceskey

​Found out that hair cards is just an experimental make me a little bit sad. Performance gain a lot with hair cards. This should be the solution for this gen while the regular groom is suitable for the next gen.

What’s stopping you from using the feature even if it is experimental? I guess there is the potential for bugs/issues but as long as you test it thoroughly it should be fine to ship a game with right?

@scha

I don’t understand, what do you put in “Procedural Mesh” field? On the screenshot it’s called “Cards_Mesh_Group” I think?

Maybe that mesh was generated when he selected ‘Procedural’ from the dropdown menu? Have you tried it?

[scha (scha (inu games))]

@freaknbigpanda

Maybe that mesh was generated when he selected ‘Procedural’ from the dropdown menu? Have you tried it?

You have to put 0 or more in the LODIndex field on the bottom of that tab, then choose “cards” in the LOD tab, that does the trick

[elettrozero]

@Chosker

thanks for this info!
I compiled the 4.26 branch on GitHub and I can confirm the new Experimental Water Plugin is there

Done the same but it seems the plugin is not quite ready yet.

[tofuscrambled]

Ray tracing shadows does not work in 4.26 yet? When “Cast Ray Tracing Shadows” is enabled under any light, it renders all wrong

[RoyAwesome]

Are physics asset setups built in previous versions of Unreal Engine expected to just work with Chaos now that PhysX is deprecated?

All of my vehicle setups are broken in 4.26. I even pulled down some assets from the marketplace that were broken, and the vehicle sample project is broken. I cannot seem to get vehicles to function.

[MostHost_LA]

@RoyAwesome

Are physics asset setups built in previous versions of Unreal Engine expected to just work with Chaos now that PhysX is deprecated?

All of my vehicle setups are broken in 4.26. I even pulled down some assets from the marketplace that were broken, and the vehicle sample project is broken. I cannot seem to get vehicles to function.

its the editor thats not ready yet. This release doesn’t have physx parity.

[S-ed]

Small icons are missing from UI.

[EverFire]

how to switch mobile preview. click （ Setting -> Preview Rendering Level -> Android ES 3.1 ） there is no any response. Someone has the same problem as me

[anonymous_user_a8c95a8e]

Enabling HZBO causes the 4.26 Preview 2 to crash:

Fatal error: [File:/Build/++UE4/Sync/Engine/Source/Runtime/RenderCore/Private/RenderingThread.cpp] [Line: 907]
Rendering thread exception:
Assertion failed: !bIsLoadActionInvalid [File:/Build/++UE4/Sync/Engine/Source/Runtime/RenderCore/Private/RenderGraphValidation.cpp] [Line: 421]
Pass 'TestHZB' attempted to bind texture 'HZBResultsGPU' as a render target with the 'Load' action specified, but the texture has not been produced yet. The render target must use either 'Clear' or 'NoAction' action instead.

UE4Editor_Core
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ntdll

0x00007ffd009a3e49 KERNELBASE.dll!UnknownFunction ]
0x00007ffcbfd5e9c6 UE4Editor-Core.dll!UnknownFunction ]
0x00007ffcbfd620e8 UE4Editor-Core.dll!UnknownFunction ]
0x00007ffcbfa734ad UE4Editor-Core.dll!UnknownFunction ]
0x00007ffcbfa0b475 UE4Editor-Core.dll!UnknownFunction ]
0x00007ffcbfa0d520 UE4Editor-Core.dll!UnknownFunction ]
0x00007ffccf06e1df UE4Editor-RenderCore.dll!UnknownFunction ]
0x00007ffccefa5a67 UE4Editor-RenderCore.dll!UnknownFunction ]
0x00007ffccef9122c UE4Editor-RenderCore.dll!UnknownFunction ]
0x00007ffca7e0427d UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca7e4e42d UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca7878ac5 UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca7e42b02 UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca786fedb UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca7e43dc2 UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca7e190ff UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca7e2d82d UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffca7e313bd UE4Editor-Renderer.dll!UnknownFunction ]
0x00007ffcbf825ceb UE4Editor-Core.dll!UnknownFunction ]
0x00007ffcbf8260de UE4Editor-Core.dll!UnknownFunction ]
0x00007ffccef7fcf2 UE4Editor-RenderCore.dll!UnknownFunction ]
0x00007ffccef88314 UE4Editor-RenderCore.dll!UnknownFunction ]
0x00007ffcbfd7a1eb UE4Editor-Core.dll!UnknownFunction ]
0x00007ffcbfd72e80 UE4Editor-Core.dll!UnknownFunction ]
0x00007ffd01b96fd4 .DLL!UnknownFunction ]
0x00007ffd02dbcec1 ntdll.dll!UnknownFunction ]

[Menesis]

In OP it says

• Volumetric Clouds. The new Volumetric Clouds Actor provides a material-driven real-time cloud rendering system. The component requires a material to work. You can use the default one found in Engine/EngineSky/VolumetricClouds/M_SimpleVolumetricCloud.

But there is no folder called EngineSky in my Unreal 4.26 installation folder?
stupid me. It’s in the standard engine content that you can enable inside each project.

[Dazzer1234567]

nDisplay still crashes UE4.26p if you have both SteamVR & nDisplay plugins enabled… PLEASE fix this!!!

[Loux_xavier]

In Preview 2 when I try to play in VR Engine crash.

Assertion failed: !bIsLoadActionInvalid [File:D:/Build/++UE4/Sync/Engine/Source/Runtime/RenderCore/Private/RenderGraphValidation.cpp] [Line: 421] Pass 'Tonemap %dx%d (PS GammaOnly=%d)' attempted to bind texture 'Tonemap' as a render target with the 'Load' action specified, but the texture has not been produced yet. The render target must use either 'Clear' or 'NoAction' action instead.

UE4Editor_Core
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UE4Editor_Core
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UE4Editor_Core
UE4Editor_Core

ntdll

[MothDoctor]

@RoyAwesome

Are physics asset setups built in previous versions of Unreal Engine expected to just work with Chaos now that PhysX is deprecated?

All of my vehicle setups are broken in 4.26. I even pulled down some assets from the marketplace that were broken, and the vehicle sample project is broken. I cannot seem to get vehicles to function.

If you’re using PhysX Vehicles, that plugin becomes deprecated.
https://github.com/EpicGames/UnrealEngine/commit/8cd4350a309a9d0f08b8ee68d622d3038ee8c5ca

I guess, you will need rework your vehicles into Chaos Vehicles. I expect this is special area that might implemented very differently from the old PhysX version.
https://github.com/EpicGames/UnrealEngine/tree/c20d048e3a7018d4c3e6d89984c257bed9aa3e88/Engine/Plugins/Experimental/ChaosVehiclesPlugin

[Loux_xavier]

Oh and in Preview 2 with GPU Building, Emissive on Static Mesh produce light but “Use Emissive for Static Lighting” is unchecked