Hi There
I am using Obi cloth to do a balloon, I have the scene setup and working but when I exit play mode I get a load of exception errors in the console and the scene wont work again and I have to exit unity and restart, the scene then works once only before the exceptions are back. All the exceptions seem to be coming from ObiColliderWorld.
If I unload my scene and load one of the sample scenes they stop working with the same load of exceptions.

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When should adding a new solver be considered?  Obviously if I want to use different solver settings, I'll need to add another solver.  But in what other circumstances, if any, would it be recommended/not-recommended to add a new solver?  Advantages/disadvantages?

1)  Two ropes but in very different areas of the same scene.  Same solver?  Separate solvers?

2)  Two ropes but with a desire to categorize them differently?  Like if you ideally want them in a different part of the object hierarchy so they are grouped with related objects.

Thanks.

Hi everyone,

Obi 8 has entered feature freeze, which means no new features will be added before release. We're hunting bugs, writing documentation and updating the manual.

In 2-3 weeks (once the manual has been fully updated) we'll release a public beta. Any existing users who wish to try it can write to support(at)virtualmethodstudio.com with the subject "Obi 8 beta", and we'll send it once available. After the beta ends and Obi 8 is publicly released, it will be a free upgrade for all existing users, and pricing for new users stays the same.

Here's the list of major changes in Obi 8:
https://obi.virtualmethodstudio.com/manu...tsnew.html

Hope you'll find something useful in there. As always, comments and feedback are most welcome, as they'll shape what's to come during the entire 8.X release cycle.

kind regards,

I'm aware 2D lightning is not supported, but I'm just trying a little transparence, without any kind of refraction or reflection with fluids over 2D sprites. 

Opaque fluids are working nicely enough over sprites, but if it could only have a small transparence over sprites it would be perfect for my use case. 

When I try the standard universal URP, fluids become translucid and do not take any colors, also fluids when above spirte, even being translucid, make sprites completly vanish. 

I'm quite sure I'm using the correct set up, but would greatly appreciate if there is anyway to make my use case work. 

Thanks!

So i am making a game and i want to simulate a usb cable. So i created a rope and added on both sides a  VR Grabbable game object with Particle attachments.
So when something hits USB connector it moves nice with cable, but my issue now is when i move the cable with controller/hands it lags behind, i tried changing
to Synchronous Fixed mode and setting interpolation to none but it did not help.

i found this old thread where it says to use LateFixedUpdate, that sounds similar to this S.Fixed but like i say it does not fix it for me. Should i try to downgrade
to version 6 so i can try LateFixedUpdate? Any other solution? I wasted full day trying to fix this

Hi, my English isn't very good, so I used AI to translate and summarize this article. Thanks for understanding!

My setup
- Obi Fluid 7.x, Unity 6000.3.24f1, URP, IL2CPP, arm64, Managed Stripping = Minimal, Development build.
- Device: Samsung Galaxy S23 (SM-S9180), Adreno 740, Android 14. Repro on both Vulkan 1.3 and OpenGL ES 3.2.
- In the Editor (desktop, Compute backend) everything works perfectly (~120 fps).

Problem
On device the screen is black. Logcat shows this NullReferenceException repeating every frame:
NullReferenceException: Object reference not set to an instance of an object.
  at UnityEngine.Rendering.Universal.UniversalRenderPipeline..ctor (UniversalRenderPipelineAsset asset)
  at UnityEngine.Rendering.Universal.UniversalRenderPipelineAsset.CreatePipeline ()
  at UnityEngine.Rendering.RenderPipelineAsset.InternalCreatePipeline ()
  at UnityEngine.Rendering.RenderPipelineManager.TryPrepareRenderPipeline (...) at UnityE
The whole URP pipeline fails to be created, so nothing renders.

Key finding — it is the Obi Fluid Renderer Feature
- With the Obi Fluid Renderer Feature ENABLED on the URP renderer → the NRE above → black screen.
- With the feature DISABLED → URP renders fine (I can see the scene and the raw fluid particles), no NRE.
- Reproduced with both Compute and Burst backends.
- Reproduced with both Vulkan and OpenGL ES 3.2.
- The stack trace contains no Obi frames or line numbers (IL2CPP), just URP internals.

The simulation itself runs on device
Obi's own warning appears in logcat: "Hashtable usage should be below 50% ... Increase max surface chunks in your ObiSolver" (from Obi...<Render>), so the solver + surface mesher are running — the crash is specifically in the URP renderer-feature / pipeline construction.

Separate issue I already worked around (maybe related)
With the Compute backend I first got:
ArgumentException: The total size of the graphics buffer (150994944 bytes) exceeds the maximum buffer size. Maximum supported buffer size: 134217728 bytes (mobile's 128 MB GPU buffer cap).
I traced this to the surface mesher buffers (maxVoxels = maxSurfaceChunks * chunkRes^3). Lowering ObiSolver.maxSurfaceChunks from the default 32768 to 16384 removed that ArgumentException. But the UniversalRenderPipeline..ctor NRE (above) still remains.

Question
Why does the Obi Fluid Renderer Feature make UniversalRenderPipeline..ctor throw a NullReferenceException on this Android device, and how can I get the URP fluid renderer to work on mobile? Is there a known fix / required setting / shader change for Adreno / Unity 6 / URP 17?

Thanks!

How do I add end caps to the rope extruded renderer?

Using the chains from the sample scene in a new scene with a large cube for a floor.

When surface collisions are off they sit still on a large cube but when surface collisions are on they jitter about.

I need the surface collision turned on otherwise a thin rope will pass right through the chain.

The rope doesn't jitter with surface collision on.

The rope has a thickness of 0.04 and resolution 0.113 and has surface collisions on
The chain has thickness 0.1 and resolution 0.43

I've tried having more or less substeps in the solver, only using cpu backend cos nothing appears on the gpu backend

What's the solution to have chains that don't allow ropes to pass through and doesn't jitter?

Has anyone got an example script to save and load the position of ropes?

I was experimenting with a rope tethered on one end, with a loose rigidbody attached on the other end.  Then I had a mesh with a big hole in it that I added an Obi Collider to.  I pushed the rigidbody through the hole and it fell through pretty normally.  But then if I start moving the rigidbody it can start to cut through the mesh collider of the model with the hole.

This can seemingly be fixed by adding an Obi Rigidbody to the rigidbody (had to tinker with collision categories so rope wouldn't freak out due to having the end embedded in the rigidbody object, putting them on different categories), and then also setting the attachments dynamic.  I assume that is the correct procedure.

I'm still having issues with initialization though.  Even though the entire rope is suspended above the mesh with the collider before starting, after going into play mode sometimes part of the rope is stuck inside or beneath the mesh with the hole in it.  How to I avoid this reliably?

   

Thanks for any tips,

EDIT:  I added a couple of screenshots for reference.  Put them together in one image as I was having trouble getting it to accept attachments.  One is the layout as it looks in the editor.  The other is in play.  The rope has moved a bunch from it's starting position and part of it has embedded in the mesh beneath it.

- Skotty