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Rope Moves across objects Issues - Barax94 - 30-08-2024

Can you please help With below issues & desired behavior:

Video Link
https://youtu.be/TKmrRWXuSQE


Overview of what Im trying to acheieve

I have a rope with two control points: 
  • Start, is freezed on roation and postion
  • End, this attchment will be moved using XR-Grab and it is freezed on rotation-xyz and only moves on X & Y.
  • Currentlly both Attached Dynamic
What I need:
  • this rope to be smooth and NOT jittery as in the video-link andfor that i used settings in images below
  • This rope should collide with those cylender and not slide on them, here i tried to use [ High-Friction ]
  • Rope should either stretch or increase in length in smooth/good way, while im moving it using XR-Grab  (Giving that Start atttchments is freezed-xyz). Also the initial length of rope should be normal not too long as shown in the picture below, only when i move its End-Control-Point then it should sterch or increas legnth
Issues Im facing Overall:
  • OBI Particles Renderer not showing not showing particles, attached is settings used
  • As you can see in Video-Link,,, rope is bouncy, jittery & Rigid mainly when it touches those objects
  • When moving one end  of the rope. The ends becomes not perfectly alined with the attachments. Gab is seen
  • Rope is not colliding very well (OBI colliders and filter are set alreaddy). And it snaps

Note* Im not using code currently . Mainly im using the OBI rope. componenets configs 

I Know im asking alot but,  can you give/share me the best setting for (The solver, rope & attchments) to solve those issues or is if it's (allowed/possible) to have a Breief Technical Session to achieve that 



RE: Rope Moves across objects Issues - asimofu_ok - 30-08-2024

May also need information on Blueprint and path editing.
In the case of particles not being displayed, is it simply because the Resolution of Blueprint is too low and particles are not being generated?


RE: Rope Moves across objects Issues - josemendez - 30-08-2024

Hi,

(30-08-2024, 01:24 PM)Barax94 Wrote: this rope to be smooth and NOT jittery as in the video-link andfor that i used settings in images below

Make sure the rope is not colliding against the object it is attached to. Attaching a rope inside or very close to a collider set to collide with it will lead to jittering, since it is impossible for the rope to be simultaneously inside the object (what the attachment wants) and outside of it (what collisions want). This situation and its solution are described in the manual, see "attachments inside colliders".

(30-08-2024, 01:24 PM)Barax94 Wrote: This rope should collide with those cylender and not slide on them, here i tried to use [ High-Friction ]

This doesn't make any sense whatsoever: what you want is precisely the rope to be able to slide over the cylinders, otherwise how are you going to weave it in between them if the rope just sticks to the surface of the cylinders when colliding with it? You must set friction to zero.

(30-08-2024, 01:24 PM)Barax94 Wrote: Rope should either stretch or increase in length in smooth/good way, while im moving it using XR-Grab  (Giving that Start atttchments is freezed-xyz). Also the initial length of rope should be normal not too long as shown in the picture below, only when i move its End-Control-Point then it should sterch or increas legnth
[/list]Issues Im facing Overall:

What you describe here doesn't make sense either, I believe you're rather confused about this: stretching and increasing length are two completely different things that lead to completely different behavior, both in the real world as well as a simulation.

- Stretching means the "amount" of rope stays the same, but it is forced to spread out over a larger distance. In the real world, this might lead to the rope breaking - or if the rope won't break, make it impossible to stretch it further. In a simulation, if you force the rope to stretch too much collisions will start to fail since the amount of particles stays constant, but the distance between them increases greatly.

- Increasing the length means "more" rope is created. In the real world this might mean you're reeling out rope from a coil. As a result, as long as there's enough rope left in the coil you can continue pulling without it breaking. Once there's no more rope left, you won't be able to continue pulling.

So you have to choose one of these behaviors. I believe that increasing the length makes most sense in your case, since stretching will lead to the rope spacing particles apart too much. This requires writing code that uses a ObiRopeCursor to change the length of the rope to match a target tension: the rope will elongate itself to follow the user's hand, and will shrink when the tension drops below a threshold. This is similar to an auto-reel coil in the real world.

(30-08-2024, 01:24 PM)Barax94 Wrote: OBI Particles Renderer not showing not showing particles, attached is settings used

Make sure they're not hidden by the rope's own geometry, try disabling the ObiRopeExtrudedRenderer component. Also make sure the material you're using is compatible with your current render pipeline.

kind regards,


RE: Rope Moves across objects Issues - josemendez - 30-08-2024

(30-08-2024, 01:43 PM)asimofu_ok Wrote: May also need information on Blueprint and path editing.
In the case of particles not being displayed, is it simply because the Resolution of Blueprint is too low and particles are not being generated?

Could simply be that your particles are too small to be seen. Could you share your blueprint settings as well as your ObiRopeExtrudedRenderer settings?