Hi,

Let's say I have a bunch of points that I have created, and I want to treat them as particles in a popnet - how do I do this? Is it possible to do this without emitting from the source points for one frame? I noticed that you can set the initial geometry for the popobject node, and gravity and forces do effect these points, but no pop nodes do anything at all.

How do I get the pop solver to consider these points as particles?

I have attached a simple example.
(Note: The popsource node has the Geometry Source set to ‘Use DOP Objects’, but this is undocumented)

Where is the Problem with Emitting from Points at Frame 1? Source from Point, And incoming Pointcount in birthrate Field.
If you er happy with simple noises there is still the particle sop set to modify source.

Cheers

Modified your file

yes you are right it was kinda my habbit to use source giving me more option such as life etc..

Hi!

I ended up deleting my posts because I wrote something stupid… like repeat what the OP had already said

I guess it all depends how much work you like doing in SOPs, if what I want is to use POPs to advect an ‘object’, then I much prefer to apply those attributes on the object itself in SOPs. If the points are in fact a source for multiple other points, the POP source would be my way to go.

EDIT: I had a look at the original hip, and deleting the pop source node seems to give the expected behaviour…

friedasparagus
EDIT: I had a look at the original hip, and deleting the pop source node seems to give the expected behaviour…

Yes indeed - that's what I was looking for.
I'm relatively new to the world of DOPs, and all of this is slightly different to SOP land. So I guess that the POP Source node is needed to spawn particles from geo and assign all the attributes (age, life, etc).

So, I'm still curious about what the POP Source > Source Tab > Geometry Source > Use DOP Objects option actually means.

Here's a little example of using a DOP object as a particle source. What's quite groovy here is that the pop wind is not affecting the sphere at all directly. What's making the sphere move is the collisions with the particles that are being affected by the wind

If you try changing the ‘Affector Relationship’ on the merge1 node to ‘left input affects right input’ you'll see the ball stop being dragged over to one side.

Oh yes, one more thing that might be of interest… Try digging in to the POP source node, you should be able to unlock the asset as well (because Houdini is bloody great). You'll see that it is basically a SOP network…

friedasparagus
Here's a little example of using a DOP object as a particle source. What's quite groovy here is that the pop wind is not affecting the sphere at all directly. What's making the sphere move is the collisions with the particles that are being affected by the wind

Thanks for the example. It's sort of obvious now

If you try changing the ‘Affector Relationship’ on the merge1 node to ‘left input affects right input’ you'll see the ball stop being dragged over to one side.

This is interesting. I had no idea that pop nodes could affect RBD objects.
Also, I noticed that you wire in the popsource, popdrag and popwind all into a merge - is this any different to wiring one into the other? (So popsource is wired into popdrag, and popdrag is wired into popwind)