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Prevent rope stretching - Printable Version

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Prevent rope stretching - Tomek - 31-03-2022

Hello,
I have some issues with ropes. Is it possible to prevent ropes from scratching? 
I attached a rope to two static entities that I can pick up and move. I want the rope to always remain the same length.


RE: Prevent rope stretching - josemendez - 31-03-2022

(31-03-2022, 11:43 AM)Tomek Wrote: Hello,
I have some issues with ropes. Is it possible to prevent ropes from scratching? 

There's two main factors that contribute to spurious stretchiness (in any physics engine, not just Obi):
- Too high spatial sampling (too many bodies/particles)
- Too low temporal sampling (too large timesteps)

To fix the first one, you can reduce your rope's resolution.

To fix the second one, you can just use more substeps (setting found in the ObiFixedUpdater component). This will increase overall simulation quality and reduce stretching.

The manual contains a very detailed explanation of what iterations/substeps are and how they affect overall sim quality:
http://obi.virtualmethodstudio.com/manual/6.3/convergence.html

(31-03-2022, 11:43 AM)Tomek Wrote: I attached a rope to two static entities. I want the rope to always remain the same length.

If the objects are static and the distance between them is always <= rope length, simply using more substeps will do.