Hi,

I am using Obi Fluid 7.0.4 in Unity 2023.1.3f1 with Universal 2D, and I encountered the following error message:

Hi,

I am testing collision between Fluid and cloth. 
Works fine between ObiCloth and ObiFluid, but when switching to ObiTearableCloth, fluid doesn't collide anymore with Tearable cloth. Do I need extra setup for collision to work ?

thanks,
Diego

First off, I just want to say how amazing Obi Fluid is! I've had so much fun creating various liquids for my projects—huge thanks for the fantastic work. Keep it up! 

The Issue:
I initially ran into an issue with the compute backend struggling when handling a large number of colliders in the scene. The fluid wouldn't collide with anything, but I found a fix on the forum by adjusting:

• Colliders: ~150 (mostly Box Colliders), positioned close together.
  
• Fluid Resolution: 3
  
• Particle Count: Around 185k particles—at this point, the fluid starts ignoring colliders and becomes jittery.
  

1. Instability at High Particle Count
   • Even with a high-end GPU, the compute backend becomes unpredictable when the particle count increases.
     
   • Reducing the resolution only delays the breaking point.
     
2. Collisions Causing Jitter
   • The fluid behaves erratically when colliding with many objects, even with particle count around 100k.
     
   • This jitteriness leads to excessive foam generation.
     

1. Jittering Fluid at High Particle Count 
   demo
   
2. Fluid Passing Through Multiple Colliders
   demo
   

Hi, in my company we have Obirope asset and i have a few problems setting it up.

We have overcomplicated vr setup using MetaXR sdk. Obirope 7.0.3, burst solver. 
There is image limit on forum so i uploaded it here. In Editor it looks ok (attachment 1. Cables in editor image),
but when app is built and run on quest2 cables are not snapped in place(attachment 2. Cables on the device).

Attachments 3-7 show my in editor setup. On image 4 control points on the edges collide with noting. Image 7 shows attachments that are set up on both sides of rope.
Stuff is connected to each other using meta SnapInteractable to SnapInteractor connection creating ”chains” of objects (they must be coupled/decoupled dynamically).
I also tried to write custom script for forcing renderable position into target Transform position. Sadly there is no visible change on the device.

Another issue is that I have problems with setting up rope as cable so it will behave more like cable, not like rope. Any suggestions?
And fps drop (-20fps) but I assume it's caused by multiple ropes, for now I just want rope endings to attach. 

Please let me know if I can specify something more or you need any additional information regarding my setup.

I'm working on this scene where I have a chain that is connected to 2 hooks. Both particle attachments are set to static. In the first attached image "Editor Setup" you can see how the setup looks in the editor. When I run this scene, the green mesh rotates downwards (due to the rigidody and hinge components) and we get the second image "Scene Running (Static)". Up until now everything is behaving as expected. 

Since I want the amount of strain on the chain to influence the rotation of the bottom hook (green mesh) I make the bottom particle attachment dynamic (and add the needed obi collider and rigidbody components to the bottom hook). When I don't change the settings of the chain, running the scene will lead to very erratic behavior: The chain immediately disconnects and all the components just start shaking uncontrollably (seen in image 3 "Dynamic No Changes").

I then tried modifying the chain constraints but it always results in a chain that doesn't have enough strain on it and that doesn't connect to the the mesh properly (as seen in image 4 "Dynamic With Stretch Compliance").

In the fifth attachment "Constraints" I have the constraints I used for the static image and the dynamic one + the Obi Solver settings. I tried tweaking every possible constraint to get a working dynamic attachment but nothing has worked. Any ideas what I could possibly be doing wrong?

Thanks in advance!

Attached Files

Thumbnail(s)
                   

Hello!

Using Obi Rope, I'm trying to make a simple system where a rope is connected to a wall (attachment pin), and to an object that the player can control (another attachment pin); both of those static. I want to make sure that when the object moves away from the wall attachment, the rope gets longer, and when it gets closer, the rope gets shorter. I'm using a cursor, and I tried a few different solutions, but I couldn't get it to work. Here is the current code:

We have a system where a virtual garment is procedurally generated, consisting of multiple fabric shapes stitched and stretched around the character model. I’ve noticed an issue where the fabric vibrates and sometimes clips through the model, and I think this is because of the fabric being stretched too tight.

I tried loosening the stretch scale and stretch compliance (they’re normally at 1 and 0 respectively), but any value loose enough to stop the vibrating also resulted in the fabric drooping and losing its shape (more than it already does). I compensated by increasing the particle inverse mass (to try and decrease the mass and make the fabric less likely to droop down), but this makes it start vibrating again.

Another solution I thought of was to directly modify the mesh before generating. The cloth has two halves, front and back, which are initially flat meshes. I made some code that uses raycast checks to manually modify each vertex, to make the mesh wrap more closely around the body. This reduces some of the vibration, but still has some jittering and causes the fabric to droop (albeit in a slightly more crinkly and polygonal way).


I've been thinking about making a system to have most of the garment non-simulated. so it conforms to the model and doesn't move about in ways it doesn't need to, but since the garment is procedurally generated I'm not sure yet how to differentiate between the bits that need to simulate realistically and the bits that can stay in place.

What other methods could I try to reduce jittering?

Thanks!

Is it possible for a Unity (non-Obi) collider to detect interaction events with Obi colliders? Do Obi colliders adapt according to the shape of a deformed object? I intend to use it for haptic feel so shape of colliders is important. I added a Unity mesh collider with softbody and that does not appear to deform with particles. Kindly suggest any possible approach.

I'm trying to attach some objects to a softbody via Obi Particle Attachments. 

I created some particle groups in the blueprint and assigned the objects to their respective particle group in the attachments. I want the objects to maintain their orientations relative to their particle group and I don't want the attached objects to influence the softbody if possible. I've tried every option and configuration I can think of, but the behavior is always undesirable or unstable.

   
I want the spikes to stick out of the ball like this and maintain their relative positions and rotations as the ball rolls around.


  SoftbodyAttachments.gif (Size: 787.22 KB / Downloads: 10)
Instead the objects drift away from the surface or roll around their local axis. They also seem to pull the softbody around a bit instead of just going along for the ride, which is undesirable.

Is there a way to achieve the behavior I'm looking for? Or maybe I'm missing something with my setup? Any thoughts are appreciated. I can link you this project if you'd like to see my setup. Thanks!

Hi! 

I had to upgrade Obi Rope from version 3 to 7 because I bought Obi SoftBody as well, and unfortunately, they don't work on separate versions. 

I’m not quite familiar with this version yet. 

How can I generate a ropes that always has the same length? 
Currently, it generates the rope based on the distance between the Start and End points, but I don’t want that. I tried using "controlPoints.Add(Vector3.down * ropeLength);" like in the old version but it's does not work anymore.