Basic particle sim questions

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Hello,

I have two basic questions regarding particle simulations in Houdini.

I have a very simple setup, where I make particles emanate from a human base mesh, and instance some simple geometry onto the particles to export the simulation as alembic to 3rd party software (Blender).

The first problem is that the simulation seems to duplicate all particles and place them at 0,0,0 global in global space (see the tiny sphere in the picture foreground). This is unwanted, because the geometry from these particles will show up in final render in Blender, and because it makes the simulation heavier than it needs to be. How can I get rid of it?

My second problem is that whenever I export the simulation as Alembic (with the setup also shown in the picture), Blender seems to read every particle as an individual object. Is there any way to merge all the geometry into a single object from Houdini before export? There is no option in Blender to make it read the file as a single object.

Thanks in advance!

//William

Attachments:
Particles at 0,0,0 P.PNG (535.9 KB)

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Hi Wiliam,
Would it be possible if you could attach your Houdini scene file to this post? I might be able to offer better insight after reviewing your setup.

With regards to the cause for the particles birthing at the origin, I assume there is geometry located here and is acting as a source for particle births. Possibly the centroid point of your human geometry which you imported to Houdini from another program? Try blasting that point.


When exporting a particle sim it is better to practice to use a file cache node. This might have the features you are looking for.

Regards,
Kimber
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Kimber
Hi Wiliam,
Would it be possible if you could attach your Houdini scene file to this post? I might be able to offer better insight after reviewing your setup.

With regards to the cause for the particles birthing at the origin, I assume there is geometry located here and is acting as a source for particle births. Possibly the centroid point of your human geometry which you imported to Houdini from another program? Try blasting that point.


When exporting a particle sim it is better to practice to use a file cache node. This might have the features you are looking for.

Regards,
Kimber

Thanks for the reply, Kimber.

I have attached the .hip file.

The birth at the origin is created by the POP Solver for some reason. A user on another forum suggested that the points on the origin may be some deleted particles in the sim that the instance node try to retrieve and then it just pop some particles at (0,0,0) to keep the @ptnum logic, but I still don't know how to get rid of them.

As for the export issue, I'll try using the file cache instead, as you suggest!

//William
Edited by WAV94 - July 29, 2020 06:14:41

Attachments:
Particle_Sim.hip (443.9 KB)

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Hi William,
Would you be able to lock your assets to your Houdini scene file? Unfortunately, the source asset is not included with your attachment.
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Figured it out! It had something to do with the POP Wrangle nodes in the DOP system causing the trouble.
But thanks anyways!
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