Birth particles on shape surface?

[mitchfx]

Sorry yea I was just going by memory..."parent shape surface" is the correct label. It should sample a random point on the shape of the particle that's doing the spawning.

As for sending out particles, the spawn operator has its own little output nub as you can see, and that will send all child particles. Child particles copy all properties of their parent, but you can strip those out in the next event. For example, there is a "shape remove" operator that removes a particle's shape, and you can tweak how much spin/speed/scale child particles will inherit from their parent in the spawn operator itself.

Attached is an image/flow showing some particles with large shapes having smaller particles spawned on them.

One extra thing worth mentioning: when setting up this test I noticed at lower spawn particle counts, the distribution on the parent shape surface seems oddly biased (not all faces getting same # of particles)...most likely a bug. I will fix that for the next release.

Ah that makes sense.  The clumping bias was what I was seeing, so explains why I thought I might have the wrong mode checked.  Your flow screengrab makes sense, even though I did the opposite thing on my end (spawning a single clone of the birthed shape particle, piping that out into a new event, then spawning the new ones on surface while killing the parent).  Although your method is cleaner, would it cause extra overhead if the spawned particles inherit the shape of the parent (assuming the parent has a much more complicated mesh shape) and then gets piped into the new even and assigned a new shape there?  Or does tyFlow evaluate the entire flow first and skip such redundant things?  Just curious from an optimization point of view.  

In terms of spawning, are there any plans to add more surface distribution controls?  Texture based, matID, uniform vs random, face center, vertex etc?  I also posted a feature request for more controls of the spawn particle offsets.   

Thanks!