Tutorial: Scene Interactions with Niagara Fluids

General Tutorial & Course Discussions
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Niagara Fluids can collide against many component types. This tutorial will introduce methods to allow your fluid simulations to react to the world they occupy.

https://dev.epicgames.com/community/learning/tutorials/8kkP/scene-interactions-with-niagara-fluids

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Hey Dan,

Thanks for the great tutorial. Can I ask how would I customise this to work with a character who isnā€™t a player but is keyframe within sequencer then ideally render out the interactions in mrq?

Many thanks

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Hi Dan
sorry, but iā€™m french and your accent is very difficult for me and the video has no transcript or subtitle
can you add that?
thanks

4

Also after much testing we canā€™t get these fluids to appear in mrq. Any more tips on this would be hugely appreciated.

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ā€˜Use Physics Asset Collisionsā€™ is gone in 5.1. It seems itā€™s removed from Grid3D_ComputeBoundary. If itā€™s intentional, whatā€™s the workaround for the tutorial steps?

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Iā€™m having the same problem! Did you find an option?

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hey, same on UE5.3 - there is no ā€œUse Physics Asset Collisionsā€ option. Any idea how to solve this issue? Thanks in Advance! :smiling_face:

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Please, @DanPearson we need your wise suggestions :sunglasses: :smiling_face:

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Apologies, my notifications are not working so great!

With the latest templates colliding against skeletal meshes should ā€œjust workā€.

Under the hood we are using the Rigid Mesh Collision Query module which will grab all meshes inside the bounds of the fluid. For skeletal meshes that includes distance fields from capsules etc.

You can filter the meshes it finds if your scene is complex by adding an actor or component tag to the emitter. Then add the same tag to the meshes you want to collide against.

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You can also debug your collisions by activating ā€˜Debug Collision Volumeā€™ under the Debug tab. This will copy the boundary condition into the Density attribute so you can render it as a volume.

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This should all work the same way via MRQ.

Iā€™ll try to find some time to update the tutorial.

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thanks a lot for the reply.

11

What is the technique for getting the VR Hands from the VR Template to interact with the Fluid sims? Iā€™m using deferred shader and disabled stereo rendering, so the fluids work fine in the headset, but my hands donā€™t interact with the fluid at all. Grabbable objects, like the cubes in the VR Template, can be picked up and then interact with the fluid correctly. Iā€™ve tried changing collision settings on the hand meshes inside the VRPawn to blockalldynamic and physicsactor with no success. Any ideas?