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I'm trying to use Obi Rope to make the chains in a disc golf basket.

I've tried adding colliders to the chain blueprint and can't figure it out.

I've followed the tutorials and read through the documentation and I can get rope working just fine, but not chains.

Is there a way to render a rope component as a chain, or to add colliders to the chain object?
Hi,

Quote:Is there a way to render a rope component as a chain, or to add colliders to the chain object?
Simply swap the default ObiRopeExtrudedRenderer component with a ObiRopeChainRenderer component. See:
http://obi.virtualmethodstudio.com/manua...modes.html

Quote:I've tried adding colliders to the chain blueprint and can't figure it out.
You don't need to add collliders to a rope/chain, or to any Obi actor for that matter. Obi is a physics engine of its own, particles (which is what ropes are made of) already react to collisions by themselves. You only need to add colliders to other objects that you want the rope to collide with. See:
http://obi.virtualmethodstudio.com/manua...sions.html

Colliders are part of Unity's physics engine, with which Obi can interact, but otherwise they're not needed.
(09-07-2021, 06:00 AM)josemendez Wrote: [ -> ]Hi,

Simply swap the default ObiRopeExtrudedRenderer component with a ObiRopeChainRenderer component. See:
http://obi.virtualmethodstudio.com/manua...modes.html

You don't need to add collliders to a rope/chain, or to any Obi actor for that matter. Obi is a physics engine of its own, particles (which is what ropes are made of) already react to collisions by themselves. You only need to add colliders to other objects that you want the rope to collide with. See:
http://obi.virtualmethodstudio.com/manua...sions.html

Colliders are part of Unity's physics engine, with which Obi can interact, but otherwise they're not needed.

Hi,

The chain in the demo scene does not register a collision with a cube with a collider & obi collider attached to it, while a rope does: https://imgur.com/a/kAAvm9T

That said, switching to the chain renderer component on my rope worked well: https://imgur.com/a/QFEVh5M

Thank you for your help.
(09-07-2021, 06:43 AM)obiropequestion Wrote: [ -> ]Hi,

The chain in the demo scene does not register a collision with a cube with a collider & obi collider attached to it, while a rope does: https://imgur.com/a/kAAvm9T

Hi there,

In 6.2, the old ollision detection filtering has been replaced by a newer system (see "collision filtering" in the collisions manual page:
http://obi.virtualmethodstudio.com/manua...sions.html)

That particular sample scene has incorrect filtering settings, old settings might have slipped trough unchanged during submission. I will correct it  (just enter path edit mode and set the chain's "Collide with" property to "Everything"), and resubmit the asset. Thanks for reporting!
(09-07-2021, 11:10 AM)josemendez Wrote: [ -> ]Hi there,

In 6.2, the old ollision detection filtering has been replaced by a newer system (see "collision filtering" in the collisions manual page:
http://obi.virtualmethodstudio.com/manua...sions.html)

That particular sample scene has incorrect filtering settings, old settings might have slipped trough unchanged during submission. I will correct it  (just enter path edit mode and set the chain's "Collide with" property to "Everything"), and resubmit the asset. Thanks for reporting!

Thank you, I was able to get my chains working with collisions. Kudos for the quick support.

I noticed that the Rope Extruded Renderer component has the option to modify the collider area with the "Thickness" field, shown in your tutorial here: https://youtu.be/4i177iXR23o?t=261

The chain renderer component is missing the thickness field: https://imgur.com/a/wAyG7n1

For my use case, the colliders overlap at their default size and the chains are always colliding with eachother: https://imgur.com/a/ia3en3e

Is there a way to modify the thickness of colliders on the chain renderer component?
Hi there,

"Thickness" scale only makes sense for extruded renderers, as it scales the size of the shape being extruded in the other 2 axis. Note this simply scales the extruded shape to make it thicker or thinner than the actual particles, so it does not affect physics in any way. From the manual:

Quote:Thickness scale : Scales the actual mesh thicnkess with respect to the particle radius. A value of 1 will generate a mesh that fits the particle radius exactly. Larger values will make a mesh thicker than the particle representation, lower values will make the mesh thinner.

For chains all 3 axis are free, so instead you have a link scale parameter that lets you scale all 3 axis independently. Again this is only affects visuals, has no impact on physics simulation.

If you want to change the physical thickness of the rope particles, you can do so in the path editor, on a per-control point basis. See:
http://obi.virtualmethodstudio.com/manua...setup.html

kind regards
(12-07-2021, 07:53 AM)josemendez Wrote: [ -> ]Hi there,

"Thickness" scale only makes sense for extruded renderers, as it scales the size of the shape being extruded in the other 2 axis. Note this simply scales the extruded shape to make it thicker or thinner than the actual particles, so it does not affect physics in any way. From the manual:


For chains all 3 axis are free, so instead you have a link scale parameter that lets you scale all 3 axis independently. Again this is only affects visuals, has no impact on physics simulation.

If you want to change the physical thickness of the rope particles, you can do so in the path editor, on a per-control point basis. See:
http://obi.virtualmethodstudio.com/manua...setup.html

kind regards

That is exactly what I needed to know, thank you. I now have just the solution I was looking for: https://imgur.com/a/pEFVqpF
(13-07-2021, 01:30 AM)obiropequestion Wrote: [ -> ]That is exactly what I needed to know, thank you. I now have just the solution I was looking for: https://imgur.com/a/pEFVqpF
Just wondering if there is a YouTube chain tutorial ??
(25-11-2022, 07:58 PM)idmah Wrote: [ -> ]Just wondering if there is a YouTube chain tutorial ??

Hi!

No there isn't, but making a chain shouldn't be too difficult: just use a ObiRopeChainRenderer component, select a prefab you want to use as the link, and adjust link scale (to make links larger/smaller) until it fits your rope.

Note prefabs are be laid out along their Z axis, so if they don't align with the chain simply rotate them so that they face positive Z.
Would love a video as well!

(25-11-2022, 07:58 PM)idmah Wrote: [ -> ]Just wondering if there is a YouTube chain tutorial ??
Did you get your disc golf chains working properly? I'm doing a similar thing, not DG, but also with chains. The problem I'm having is getting all the chains connected at the bottom, and then all reacting when one chain moves/gets hit with something.
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