Crowd to Unreal Engine and VAT 3 problems

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Hey all,
What is the best way to export a crowd of 2000plus to Unreal Engine? Rigged in Maya and exported FBX to Houdini for simulation. Now it's packed and takes forever just to unpack 1 frame.

I tried VAT 3 but have a few errors. Should I use Soft or Rigid body method? The Rigid body has an error "render position and packed pscale"? And the Soft body method is stuck on "reducing polygons" for ages then an error "render_position_and_packed_normal". This is only a test with 20 people...

Thanks for any help
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Check out the the imposter tools. https://www.sidefx.com/tutorials/game-tools-imposter-textures/ [www.sidefx.com]
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joelnberg
Hey all,
What is the best way to export a crowd of 2000plus to Unreal Engine? Rigged in Maya and exported FBX to Houdini for simulation. Now it's packed and takes forever just to unpack 1 frame.

I tried VAT 3 but have a few errors. Should I use Soft or Rigid body method? The Rigid body has an error "render position and packed pscale"? And the Soft body method is stuck on "reducing polygons" for ages then an error "render_position_and_packed_normal". This is only a test with 20 people...

Thanks for any help

Currently one of the best ways is to leverage VAT3 LOD system so you can static mesh instance your 2000+ characters in UE. There shouldn't be any errors though, so please email support or if possible, post your HIP file here. You can use Rigid if your characters are made of entirely rigid body pieces, like armour pieces, this is much lighter on the texture sizes. Use soft if your characters have soft deforming parts. There are tutorials coming up the next month, but some existing info is already available on SideFX Labs ArtStation page.
Mai Ao
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Ok, thanks for that. Ill check into it and see if I can post a test scene.
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joelnberg
What is the best way to export a crowd of 2000plus to Unreal Engine

You don't need to export 2000 characters if you're planning to control them in realtime. You need to bake only one character with all necessary animations.

Bake all sections of character into one single static mesh in T-Pose with single material slot. This will coste only 1 render pass.

Control this animations in single VAT shader.

Generate the crowd as a Instanced Static Mesh with your 2000 instances.

Please keep in mind - if you will have only 1 material slot - then you will render entire crowd with single render pass.

This is the best example of 15,000 characters with 12 render passees overall, one per character type: https://youtu.be/thpJebPxXSo [youtu.be]
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I am currently running into a wierd issue using 19.5.435 VAT 3.0 and UE 5/5.1

I am isolating just 1 crowd agent for the sake of testing, unpacking it so its just geo and using the Soft body preset to export the VAT. it "works" as in it loads and run in UE, but it looks not quite right and I cannot figure out why.

I have attached a few videos of different attempts and you can see how when the model is lying still ish, the points move in very odd ways, like a shimmer or just noisey. gives it this jagged look, I have tried everything from 256 to 8k in texture size and it seems to make no difference.

any pointers on why this stuff would happen would be most appreciated.

P.S. when I use a simple object like an animated box, it all seems to work fine, so I'm wondering if its something about the mesh or model or..?!

Attachments:
UnrealEditor_37ZrTETlZQ.mp4 (7.7 MB)
UnrealEditor_0hQkbRlcjc.mp4 (11.7 MB)
UnrealEditor_mkTIjcfmGG.mp4 (1.9 MB)

https://www.thomaskchristensen.com [www.thomaskchristensen.com]
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