Hi, I'm a newbie here and am testing out the power that is Houdini. However, I would like to know whether it is possible for instanced particles to take the form of any shaped geometry.

I know about the Attractor POP but that only assigns particles to surface points. I would like the particles to form the basic surface shape of the target geometry PLUS occupy the volume space e.g. a dense swarm of locusts forming the shape of bus.

How can this be done?

Thanks

look into the follow POP. that'll do what you want.

create a particle cloud in from the volume of your “bus” to which your “locusts” will be targeted.

Jerry

To fill a volume with particles simply wire in a POP network at the end of your SOP chain that defines your model. Add a single source POP in the POP network and set the Geometry source to “Use First Context Geometry”, set the Emission Type to “Volume” . Impulse Activation to “$F==1” and Constant Activation to 0. Then set Impulse Birth Rate to the the number of particles you want to fill the volume and that's all there is to it. These points could act as attractors for a second set of particles that could be your locust swarm.

Thanks guys! Jerry for the hint to look into the Follow POP and Grasshopper for the step by step instructions on how to populate a volume with particles!

The Follow POP is good for assigning motion to the particles before they form the shape I want and the filling the volume information was invaluable in actually getting numerous particles to ‘fill’ the target geometry.

Thanks to you guys once again. If I have any more questions based on this and any other topic, I know where to go!

For completeness, you might also want to know about the POP Shape Match DOP. This is a dynamics operator that (used in conjunction with a few other DOPs) allows you to treat an incoming piece of geometry like a particle system. The difference is that the connectivity of the primitives is maintained, so you can do squishy shapes and things like that.

And just to overkill this thread, there is a unsupported sop called the MetaScatter SOP. It works just like the Scatter SOP but its for filling volumes defined by MetaBalls. You can install it via the proto_install. If you need help on installing ops from the proto_install, just ask.

For future reference, we should start putting info on the wiki. Here's the proto_install page: http://www.odforce.net/wiki/index.php/Proto_install [odforce.net]