Render>Particle>??? A "how-to" question

[OneWatt]

Greetings. Sorry for this lengthy post. It's a bit detailed and I want to be clear.

Also want to preserve a full solution for anyone else coming up behind me with similar objective...

I'm trying to create an effect where a large "flock" of objects scatter from a generally central cluster outward in all directions (i.e., none inward) ... kind of like a slow-mo puddle splash effect but using  skinned/texture object. The skin texture object is no problem at all. 

But I've tried creating a "control" object (ellipse in either vector and/or raster) assigned as Control1 and then animating it from there. So far, attempting each and every kind of particle FX, linking the ellipse as a Control1 object in FX screen, I've failed to achieve my objective as described.

The Starfield effect seems to provide the closest approximation except that I cannot get it to refrain from including the creation of objects that move toward the center of the control oval. I'm trying to limit all birthed objects to move outward AWAY from the center point.

Despite reading through the documentation, obviously I'm not grasping something about how controls and particle effects work as I cannot seem to exert much control over post-birth subsequent movement thereafter (at least not using the particle FXs  as available).

1) Is there a particular particle type that's best suited for what I'm trying to achieve?

2) Can someone further clarify what all those Control parameters set to "0" mean? The documentation doesn't seem to clearly address what any # other than "0" would indicate for controls. I've simply assumed a "1" would indicate Control1, but that doesn't seem to be the case. 

Will keep trying in the meanwhile. Thanks for any insights you might have!    

p.s. - The closest I've come is to use the starfield with an ellipse as control shape and also fill in the circle with a drawing (placed above the particle level) and fill it in with some background'ish color to hide those objects moving into the center of the circle - effectively revealing only the ones moving outward. This is sloppy but perhaps a hack that will get me somewhere. 

[OneWatt]

UPDATE: Still not having a breakthrough. 

Am testing with a Matte In/Out to see if I can block in/out those particles that are wanted vs those that are not. 

Not getting close enough to desired effect yet. Will keep exploring possibilities...

[OneWatt]

As a follow up, I seem to have made some meaningful progress toward creating the effect I described above...

Using SpotSmoke Particle effect, I created a small elliptical control image (black against transparent background) and tweaked a number of variables in the Particle FX panel such that the texture image sprouts out of the ellipse in various directions and each one falls to the ground based on various mass/gravity parameters. Then I doubled the whole thing and supplied a different random seed # and it seems to work nicely for what I was after.

Hope this helps someone else trying to achieve something similar. I'd post a clip, but not sure how to accomplish that on this forum.

[Gabriel Gazzán (gab3d)]

Hi,

I just read this.

I'm glad you've found a solution.

Just to clarify to others that might read these messages in the future.

The "Control Image" parameters refer to the "Control" input ports of the Particle FX node.

Typically if you want something to be controlled by an image/image sequence you will connect the column where it's exposed to one of the Control ports and, after that, change the relevant "Control Image" parameter to use that Control port.

More in depth info on this topic can be found here.