The collision doesn’t work well

I want to make waterball but it doesn’t work well. This is my project file .
. Please help me.
test.usd (5.7 MB)

Please what version of Create are you using? I can see the particles to splash on the sphere, what is the expected behavior here please?
Thanks, regards

Hi. Thank you for replying. I am using latest version and second latest version. I want like this. Blender Tutorial - Satisfying Fluid Particle Animation - YouTube . So I want to make a container made by sphere. And I drop it and simulated it.

Yes, we can simulate it. The problem is that you are having a sphere collider which will not collide from the inside.
Instead create a sphere mesh collider, then change the mesh winding so that the normals point towards the middle, then assign collider to it and you should be ready to go, here is a video:!thank you so so so much. I can get it. This video is amazing.
I have two more questions. How do I change samples of simulation. I am using rtx 3070 , so this simulation is very heavy for me ,and sometimes shutdown the software because of lack of vram.
And I want drop the sphere like this 不思議な球体 - YouTube.
I am so beginner. I really don’t know about this software and this software is too difficult for me, so if you have time please help me.

yes kind of. But it does not work out of the box. You need triangle mesh collisions in order to have this working and such a body cant be dynamic. So what you could do is create a rigid body that is kinematic and its movement be defined by animation. See attached video:

Thank you for replying.
I see. I get it. Thank you so much .
And I have more question. I am sorry I ask a lot of questions . So if you don’t mind, could you tell me the how to simulate more lightly. In blender, I can change number of particles of simulate. Does omniverse create have similar function? Or am I able to do differently way?

I think you used the generated data from one of the demos right? Currently the particles generate the point instancer data that are simulated. So you cant just change a value atm. You could modify that demo and reduce the number of particles there.

Additionally you can do two other things:

  1. Enable async simulation → on a physics scene in advanced section
  2. Enable omni.physx.flatcache extension
    Those should give you some perf boost.

A colleague of mine tried to get this asset working with our new SDF collision path and managed to get it working very well. The difference is that the triangle mesh sphere now has a proper thickness so that the SDF collisions can be generated properly. Then the sphere can be a dynamic body, please see the attached USD scene.
FluidInRigidBall.usd (35.8 MB)

How did you add the Physics Mesh in the video?

Edit: I think I found it: Particals - Mesh.

If you could make a full tutorial on how you did this, I have tried stuff like this for 3 months and don’t get how this was made.

The mesh was generated using a python code. Then in order to have it working as SDF you add the collider with TriangleMesh approximation, next in the Advanced section you set the SDF resolution to something higher then 0, like 128, 256 and that will generate the SDF mesh. From then on you can use this mesh as part of a dynamic rigid body.
For upcoming minor release we will move the SDF approximation into its own type, so its more easier to created it.

I 'm sorry , It doesn’t work from the very first step. I try to do it the same way you do it, but I can’t do it. The collision doesn’t work and the water splash. I don’t know anything anymore. Sorry for being such a stupid questioner.

You need to add just collider, not rigid body with a collider.

If you do Add->Physics->Rigid body with collider the approximation will be a convex hull hence stuff will get pushed out. So just Add->Physics->Collider

I could do it. Thank you so much. By the way, what is the shadow in the my movie. How can I delete it.

You can uncheck the cast shadow on the sphere mesh:

I see. I want to ask about

Where I can change this value

Not sure what demo you did used, but there is a python code that generates this, you can check what the code does, how many particles it does instantiate. If you find that file on your disc you can modify it, I think there are buttons to navigate to those files.

I used demo the named “fluid isosurface. I can’t find the code. And when I try it, it will shutdown the software. How can I fix this problem.
2022-11-16 12-22-33.mkv (54.7 MB)

When you have the demo window, there is open source button and then you can see the path to the python script:

Can you please send me the log? In the log folder:

kit_20221119_171937.log (1.3 MB)