NVIDIA GameWorks Integration

[Andrew.Reidmeyer]

Why Flow is limited within GridActor ?
Wasn't the point of flow to work without such arbitrary limitations ? It severely limits it's usefulness only to statically placed effects.

Flow uses sparse 3D texture as the foundation to improve performance properties over traditional simulations based on conventional 3D textures. Sparse texture allows for only a subset of a given texture to be resident in VRAM. This allows Flow to create 3D textures covering volumes that would not fit in typical VRAM.

Sparse 3D texture does not allow for infinite address spaces, and larger address spaces require more resources to manage.

The current integration does require the bounding box to remain static. A future release will add support for a dynamically translating bounding box, with a minor increase in overhead. This will likely cover most use cases, as the grid component could be attached to the player, and cover a reasonable LOD region.

[Zero-Night]

For Flow, is there a good way to make it emit on a quickly moving object, like a character's weapon? My tests so far have had some difficulty on it, it seems to stop emitting until the object is brought to almost a full stop.

[Andrew.Reidmeyer]

On the Flow emitter, there is a parameter Couple Rate. This controls how fast an emitter moves grid values towards the smoke/fuel/temperature/velocity values set in the emitter. The default value is ideal for stationary objects, where the lower couple rate allows a better blending between the emitter and the simulation.

For fast moving objects, you can use a much higher couple rate to quickly hit the target values and still get good behavior, since the emitter will not occupy a given location for much time. You can also increase emitter sub-steps, to increase quality for fast moving emitters.

For a case like a character's weapon, would be best to dynamically vary the couple rate via blueprint, using velocity or animation information to manipulate couple rate (and sub-steps).

A future release may include some utilities to cover the common case, but blueprint will continue to offer much more control.

[overfuze]

Casting shadows onto other geometry will be added in a future release. Casting shadows from spot lights and point lights will also likely be added in a future release.

No support at the moment for rendering a single baked frame of a simulation.

The last example appears to be visualizing the smoke component, but the default allocation settings on the flow material only allocate based on temperature. To allocate based on smoke, go to the Flow Material -> Components -> Smoke, and set Alloc Weight to 1.0, and set Alloc Threshold to something like 0.05. You will see similar values on the temperature component.

To visualize the active domain of the simulation, type 'flowvis' in the console at runtime.

Happy to hear that all of those features are coming in future release

I would like to know, is there a way to "trigger" the flow emmiter (like in sequencer where there is a "particle toggle track"), and can the parameters like gravity etc... be keyframed in the sequencer aswell?

Edit: I tried, and I guess a "workaround" is to keyframe the scale of the emmiter to be 0 to deactivate it and anything above that to activate it. But the second question still stands.

[buzzdx]

I packaged for Windows x64. In fact I don't think I've ever even tried a 32-bit build.

I did notice this in the CrashContect.runtime-xml file, which again seems to be diretly tied to VXGI :-/

<ErrorMessage>Assertion failed: VXGIDLLHandle [File:J:\UEVXGI\Engine\Source\Runtime\Core\Private\Windows\WindowsPlatformMisc.cpp] [Line: 3000] &nl;&nl;</ErrorMessage>

line 3000 in that file is

check(VXGIDLLHandle);

in a function which loads the vxgi module (dll).

i checked the path the code looks for the dll. for me it looks like this when i open it in windows explorer:


maybe your dlls are missing in there?

[buzzdx]

i uploaded a simple project demonstrating the shadowing artifacts i get while using the vxgi-4.15 build.

could anybody please confirm that you get the same results as me pls?

i narrowed the problem down a bit more, it is only happening when the material has PN_Triangles tessellation enabled.
when disabled, or when using flat tessellation this doesn't happen.

screenshot of what it looks like here:


link to project: https://www.file-upload.net/download...oject.zip.html

thanks

[KradMoonRa]

I packaged for Windows x64. In fact I don't think I've ever even tried a 32-bit build.

I did notice this in the CrashContect.runtime-xml file, which again seems to be diretly tied to VXGI :-/

<ErrorMessage>Assertion failed: VXGIDLLHandle [File:J:\UEVXGI\Engine\Source\Runtime\Core\Private\Windows\WindowsPlatformMisc.cpp] [Line: 3000] &nl;&nl;</ErrorMessage>

Ya, the problem resides with packer ignoring and not recognize some macro definitions and pass all in the headers, has this VXGI- GFSDK_VXGI_x86.dll, not available in the dir, the linkage produce error's later.
In the UE4 Editor logs, warnings and messages popup about missing and truncated things about unrecognized pre def macros also.
Commenting all files with VXGI (PublicDependencyModuleNames.Add("VXGI") - /*|| (Target.Platform == UnrealTargetPlatform.Win32)*/ and removing linkage for x86 libs, fix some things.

[sbnewsom]

I've been using VXGI for lighting for over a month now and am EXTREMELY satisfied with the results and framerate (1080p not 4k). One of the major problems I'm having though is the effects on Subsurface materials. Normally my character's skin would lookk like skin, but indirect lighting on the skin makes it white/pale, as if it the material is having adverse effects from the VXGI. Is anyone else seeing this problem and is there a solution? I would love to keep using the SS affects to simulate skin, but if it's unfixed, I guess I can resort to not using SS on the material. :/

[sieumeo]

Thanks Nvidia team !

Congrats on the integration, I'm grabbing my seat for the day you release your 4.15 Nvidia tech build! I've been using your 4.14.3 build until 4.15 came out, now I'm using the official Nvidia 4.15 VXGI build while waiting <3

[MaximeDupart]

Congrats on the integration, I'm grabbing my seat for the day you release your 4.15 Nvidia tech build! I've been using your 4.14.3 build until 4.15 came out, now I'm using the official Nvidia 4.15 VXGI build while waiting <3

Nvidia released all their official 4.15 integration by now, while i actually brought every package to 4.15 from 4.14 except volumetric.
I need to double check everything as Nvidia official ports are way cleaner and relevant integrations than mine.
Also there's clear incompatibilities out of the box between VXGI and the Volumetric package.
While on the surface it might seems to work properly, there's real issues to adress, from performance to engine crashes.

The VXGI Debug feature for instance, is straight broken once both packages get merged, and creates engine crashes.

[DrifterGames]

Any news on VRWorks 4.15? Should be a powerful combination with some of the new features...

Thanks!

[sieumeo]

Nvidia released all their official 4.15 integration by now, while i actually brought every package to 4.15 from 4.14 except volumetric.
I need to double check everything as Nvidia official ports are way cleaner and relevant integrations than mine.
Also there's clear incompatibilities out of the box between VXGI and the Volumetric package.
While on the surface it might seems to work properly, there's real issues to adress, from performance to engine crashes.

The VXGI Debug feature for instance, is straight broken once both packages get merged, and creates engine crashes.

Wish I had technical background to help . I'm doing animated series in UE4 so I have the luxury of ignoring performance cost, but VXGI+Volumetric+Hairworks+Flex is a must-have in return. I really hope you could find time to update and share your 4.15 build later. Cheers man.

[Andrew.Reidmeyer]

Setting the Flow emitter couple rate to 0.0 is the best way to disable an emitter.

Blueprint timelines can be used to dynamically vary emitter parameters. The NvFlowSamplesVR project has effects that demonstrate this.

[TX_LOSER]

Nvidia released all their official 4.15 integration by now, while i actually brought every package to 4.15 from 4.14 except volumetric.
I need to double check everything as Nvidia official ports are way cleaner and relevant integrations than mine.
Also there's clear incompatibilities out of the box between VXGI and the Volumetric package.
While on the surface it might seems to work properly, there's real issues to adress, from performance to engine crashes.

The VXGI Debug feature for instance, is straight broken once both packages get merged, and creates engine crashes.

Hello, will it contain waveworks? If not, could you make a tutorial about how to merge them?

[MaximeDupart]

Can anyone confirm this issue with VXGI 4.15 ? Happens with a lot of emitters