Hello,
 
I am working on Save/Load of my obi rope. The thing is that rope changes length at runtime, so I managed that by saving length changes, positions and velocities in the solver. When I need to load the rope, I just change its length in For loop the same as I did for the rope before with the cursor.ChangeLength(len) and after that I set the same positions in solver as before and that worked in v6.x. Now in v7.0, it doesn't work anymore. The main problem, as I see it, is that the rope isn't changed immediately, but at the start of the next solver update so my positions and velocities are loaded before the rope changes. I tried waiting with Enumerators or in while loops, but none worked for me. So I changed my approach and tried with an example from this thread: https://obi.virtualmethodstudio.com/foru...0#pid16920 . When I set up this approach I got the same issue. It was all good when the rope got shorter, but when it grew and I needed to add new particles, the particles that I added weren't active. They would be in the right position but static and old particles would move normally. Is it that this new rope.ActiveParticle() without input activates one of the pooled particles? I am still trying to find a way to add particles without problem or a different approach to Save/Load the rope.
 
Thanks in advance for your reply.

Hello!

I've sent the test project to the support(at)virtualmethodstudio.com.

The project has player, and platforms attached to the rope. When the player jumps on any of them, the platforms fall down a bit and than come back to default position very sharply.
The one fix for this that I've found is use many character joints attached to each of the platforms but it is quite messy and I'm sure the solution is much simpler and all Obi-based.

P.S. Please do not answer to the email, thanks.

Kind regards,

Hello. I have an Obi Fluid Emitter of 12 Particles, which generally just sits there (purple) without any input. But I noticed that at low particle numbers, the individual particles seem to narrowly clump together, and become somewhat jittery, like boiling water droplets. They also seem to gain a lot of friction to the WASD controls, making it generally annoying/ impossible to control.

I had no intuition that it was Particle Velocities, but on trying to refine the WASD controls I discovered that bodies of 4 or less particles have these interesting symmetrical velocities. I don't know if they are pointing in or out vs the position of the centermass of the droplet.
Obi seems to modify velocities in a lot of places, and I was wondering if you could point me in the right direction. Where might there be relevant forces applied, that I can try to hook into?

I had previously attempted passing around a duplicated velocities array, and copying/zeroing it out, but it didn't work at all in the few locations I tried.

Images of Debug Velocities: various numbers of particles. At just 1 particle remaining, the particle is a bit jumpy and sometimes meanders around a little even without any input

  12 moving.png (Size: 6.58 KB / Downloads: 14)
  4 still.png (Size: 6.84 KB / Downloads: 13)
  3 still.png (Size: 10.77 KB / Downloads: 12)
  2 still.png (Size: 10.05 KB / Downloads: 13)
  1 jitter.png (Size: 6.75 KB / Downloads: 13)

There is rod with some bended initial shape and I push it into place where it's not possible to keep this shape fully. In my case it's some kind of tunnel collider.
The problem is that rod loses it's shape during that operation, like it had plastic deformation enabled. Meanwhile plastic creep and yield is set to 0.
Is that expected outcome?

Example of such a deformation below.
All constraint values are set to default (0).

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After updating to 7.1 every time I do a domain reload one part of a rope hierarchy chain spasms (one of two symmetrical ears) out by aerodynamic forces.
Interestingly, once I reduce drag for that Obi Bone component from 10 to 0, another Obi Bone component on the same Solver starts spasming out. If I restart, it doesn't seem to spasm out.

Hi, I have got several quesions about scripting rods.

1. Is there valid way to calculate rod tension? For example I need to know if rod is pressed against the wall and it's being compressed. I tried to compare compressed distances, but with chain constraint it does not work.
   
2. Is there way to calculate pressure against softbody or get it from softbody directly?
   
3. Is it possible to make different parts of rod have different elasticity? There is rotational mass, but it's hard to balance and there can't be huge difference in mass (1:10). Sometimes even if difference is not huge, the rod becomes wiggly and can't stop.
   
4. Is there way to damp rod without touching solver main parameter (damping)? I guess I could write script just for rod to reduce velocities every step, but it also affects other forces.
   
5. What is difference between changing particle velocity and externalForces?
   
6. Is it possible to change rod default (initial) shape during runtime? There are various properties like startPositions, endPositions, restPositions, any many other, but some of them has no effect and others are not what would be expected. I would expect particle delta to show something, but I think they are reset during simulation.
   
7. Is there way to "pin" my burst job to main job queue? I wish I could just add my job handle to be executed with all other stuff without need to complete job instantly.
   

Hi, when rod is attached in dynamic mode and constraint orientation is enabled, then the whole attachment becomes broken. To be precise the orientation taken into account is flipped and rod tries to keep opposite direction. This bug can be sometimes not obvious, because when rod is rotated it gets apparent stability for short time.
To reproduce, simply create box with rigidbody (can be frozen and kinematic for particles for better result) and create dynamic attachment with constrained orientation.

I want to not that it's best if box and rod is perfectly aligned and not rotated.
Attached image shows my setup before and several frames after starting simulation.

Obi 7.1
Unity 6000.0.54

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Pinhole inspector uses rope as target instead of base class for rope and rod, so when used with rods it spams console with errors.

Hello,

I am procedurally generating my world in 256x256 mesh chunks and whenever player is on one chunk, I am adding ObiCollider to it. However this blocks the main thread for a second and locks the game.

Is there a way to do this in Jobs system inside a thread?

Thanks!

Hey team,

I would really appreciate your help on this one. Its got me a bit stumped. 

When upgrading from 7.0 to 7.1 all of the connections between my rods and other objects were flipped. I tried recreating all my rods, and then I tried it in the 7.1 sample scenes in a brand new project but the issue persists. 

I am using the SpringRod sample. I have disabled the animation for simplicity. The default scene as it is works fine.
I delete the cube named load, and add in a capsule. I add a basic collider and Obi Collider, all with default settings as pictured. In the Rod settings, I set the target of the Obi Particle Attachment that was set to the cube (control point 0) to target the new capsule. I dont edit the path of the rod at all.
When I play, the rod/spring twists around to point control point 0 facing out of the capsule instead of in (see image). I dont know what I have done to cause this or how I can correct the orientation of the rod relative to the attachment when using Constraint Orientation.

Cheers,
Matt

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