Particles Along Curve Normals

[Guest ZThirtyTwo]

Hello,

I am having some trouble getting particles to move along a curve. Currently I am using groups to define the normal force, Force radius & drag for different sections of the curve. I am hoping there is easier way of moving particles along a curve with sharp turns more accurately. So far trying to manipulate these forces only results in the particles either shooting off the curve (Exiting the effect radius) or simply getting stuck along the curve. At best there's some delicate balance here but I'm hoping I don't have to spend a week trying to find it.

Hip file included with plenty of notes. Any suggestions?

Thanks,

John

ParticlesAndCurves.hipnc

[Macha]

Does this help?

Edit: forget the point2 node, it does nothing.

followcurve.hipnc

Edited November 28, 2010 by Macha

[Guest ZThirtyTwo]

Yes this helps thank you. Though I am not exactly sure how to control it. The edge force (Velocity) seems constant despite changing the force value in the point node. Is it to be controlled within the popnet?

[zglynn]

This could be another possible solution. In the on the voppop you can specify a min and max vel, and how much turbulence you want for the particles. On the vopsop the is a "normal multiplier" which can give you more magnitude on the vectors.

It's a pretty simple setup. I offset the pt numbers on the curve by one, then in vops, subtract the original by the offset to get the normals along the curve. Then in pops I transfer the normal attrib and use a voppop to manipulate it. I recommend playing around in the voppop. You can add all kinds of cool stuff to manipulate the particles.

Zach

particles_along_curve.hipnc

[Guest ZThirtyTwo]

This is the kind of solution I was looking for, the control is great. The VopPop is something I've been itching to play with for a good while. Though this file is throwing more segmentation faults than any file so far. The only way I can even get into this file is by opening the autosave file with Houdini 10 after the crash.

Ive tried installing service packs to fix the segmentation issue. My graphics card is a ATI 5650 with a dedicated gig of video memory. My build of 11 is the latest daily build as well. Ive switched my preferences on compatibility but to no avail.

That aside the setup is awesome

Thanks zglynn

[loogas]

Hi guys. This is an old topic, what do you think about translating it to Houdini 16?  
I've been trying to do this for several hours in H16 and I'm stuck. I've been working on a project with particles following a curve (using POP Curve Force and then POP Forces, POP Torque etc), everything fine but now I would like to have particles follow a curve which is turning and bending like crazy. The problem is they "escape" on sharp turns, even when I turn off all other forces (I've attached an image).
I guess POP Curve Force is too simple and doesn't give you controll over that. It works if you have the same amounts of orbit, follow and suction scale but I need them to follow only and then add some noise - no suction or orbit.
How would you go about doing this in POPnet? I found your examples in the old particle system (however the particles still don't stick perfectly to the path there - you can see them going away a bit on turns - which is physics I guess), tried to translate them somehow to the new system, but I know to little in Houdini. Here's my example/test file:
https://we.tl/DnR25hIRZv
I've included a POPVop attempt in the file which I think is the way to translate the old system to the new one, but I can't figure out how the particles should "inherit" the normals/velocity from the curve, along the curve.
Thanks for any help.