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Stop Cursor Removing Particle Attatchment - Printable Version

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Stop Cursor Removing Particle Attatchment - MisterToot - 30-01-2026

Hello! as the title suggests I'd love to be able to block the cursor from reducing the size of a rope if it is about to remove a particle that is subject to a particle attatchment. 

I have a starting rope blueprint & setup like this: 

  1. static particle attatchment (start)
  2. rope cursor (pointing towards the start like this <-0)
  3. a dynamic particle attatchment (middle)
  4. another rope cursor (again, pointing towards the middle like this <-0) 
  5. then some dynamic attatchments at the end that won't get affected because the cursors won't ever remove particles in that direction. 
See screenshot attatched. 

I'd love to block via code, the cursors from removing the particles attatched to the dynamic attatchments, and I feel like this is the sort of thing that might have already been solved 

Thanks! 


RE: Stop Cursor Removing Particle Attatchment - josemendez - 30-01-2026

Hi there!

This isn't something the cursor currently can do, it just treats pinned (dynamically attached) or fixed (invMass == 0) particles as it would any other particle. It is not currently possible to easily determine whether a particle is pinned without iterating trough all pin constraints in the solver and see if any of them references that specific particle. (in general, it's not easy to determine which constraints affect a specific particle since the system is designed to quickly answer which particles are affected by a given constraint and not the other way around)

For Obi 8 (currently in development) I'd like to implement for cursors a system similar to what we have for pinholes, that is, a valid range of the rope for them to act on, not just a starting point. This would allow you to limit the cursor to a specific area of the rope, avoiding pinned/fixed particles, or any arbitrary area you feel should be avoided.
kind regards,


RE: Stop Cursor Removing Particle Attatchment - MisterToot - 01-02-2026

All Good, I think I can simply solve this by just splitting this into a two rope setup, since I already have a length based limitation to stop the cursor removing a particle at the ropes start. 

Very hyped for obi 8!

Cheers, 
Matthew