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Recent Forum Posts

How to use POP Replicate? July 25, 2014, 2:05 a.m.


I am a bit lost with the new POP Network. Several operators seem to have disappear and the replacing ones are not so easy to use.
Beside it seems the examples in the documentation are still based on the old POP Network, which is quite confusing.

So this is my problem: I try to generate new particles based on the collisions between particles from a given emitter and the ground. something quite similar to the BounceSplit example in the documentation.

When I created my particle system it went into the AutoDopNetwork. In this network the Split is not accessible. As far as I understand, and please correct me if I'm wrong, the Split has been replaced by the POP Replicate.

The thing is I don't manage to activate the replication when the hit occurs. I though I could use an expression based on the number of particles in the group from the hit, with npointsgroup, but it doesn't seem to work (I fact I don't know what to put in the Surface_Node parameter).

- Can someone tell me how to use npointsgroup within a POP please?

Here is an example scene.

Thank you very much


Simple bouncing particles July 24, 2014, 8:22 a.m.

I played again with the scene and found that particles are bouncing as expected on other kind of objects such as spheres and boxes.
It may be due to the fact that these primitives define volumes and not surfaces.

I thet tried to thicken the surface of the grid in its Static Object DOP, and tweaks some other settings too, but nothing changed.

At lead I have an alternative to my issue by using a box instead of a grid but I still have no idea how to make a grid work in that case.

Simple bouncing particles July 24, 2014, 7:49 a.m.

Hello Rabiee,

Thank you for your answer.
I checked all the points you mentionned and everything seem to be ok and though I keep having the particles going through the grid.

This is, step by step, what I did (and I did it again to be sure):
  • - I created a grid
    - I droped a Static Object DOP from the toolbar on it. It then created an AutoDopNetwork with the solver in this network. The Static Object get connected to a Static Solver.
    - I dropped a Location Particle Emitter into the scene
    - I then dropped a Collision Detect Particles in the scene, once again from the toolbar, and selected the grid. The Collision Detect is added into the AutoDopNetwork and my particles get red when going through the grid.

    … and them what?
    Particles are still not bouncing on the grid and, well, I really don't see where to change that.

    I've attached the described scene to the post.

    Thank you once again for your help,

    Best regards