Kismet includes an action type in the category Particles called Event Generator.
The usage would seem to be something like this. You have an emitter in the scene, and you want to drive a feature of the emitter via a vector which is sourced from some other kismet action, or you want to give the vector to another object. The parameters you can base off a vector include location (where you might vary where the particle emits based on the movement of an actor), direction (where you might change the direction of the particles to face a moving actor), and velocity (where you might change the speed of a particle relative to another actor).
Kismet also includes an event type in the category Particles called Particle Event, which appears to referenced by the Event Generator just mentioned.
How does it work actually? What's a concrete example?
All I've managed to find in terms of info is the UDN Kismet Reference which just provides a pic of the node in kismet and lists the properties.
Th Event Generator action allows you to generate a particle event from Kismet that can be received by a particle system receiver module. The Particle Event kismet event allows you to execute some sequence in Kismet when a particle event is generated. Basically, particle events are a way of allowing particle systems to interact with each other and with the level.
Here is what I could gather from a quick inspection of the variables:
Location specifies where the event occurred so you can, for instance, spawn a bunch of particles in a specific location in the world.
Direction is used mainly for generating collision events. It is the direction the particle was traveling when the collision occurred.
Velocity can be for spawn events or collision I believe. So it could be the velocity the particle was traveling when it collided or the velocity to give the particles being spawned if they should inherit velocity.
I'm trying what seems like a very simple operation.
Make a trace between two notes and have a kactor be the hit object.
When hit, at the hitloc there should be a spawn of the particles assigned, but
nothing is seen.
The particle system includes a spawn event receiver module with the settings Event Name = HitEffect and Event GeneratorType = Any. I've tried with other settings but don't see a change.
Well, I got the result I wanted by swapping the Particle Event Generator that was doing SweetNothing for a simple actor factory spawning an emitter at the hit location.
But it begs the question, if I can do this instead, then what is the Particle Event Generator really useful for?
Is it for getting new particles spawned off other particles when they're traced, rather then spawning particles off hit objects like rigid bodies?
Where can I find more information/examples of Particle event stuff?
I saw an example where you can get raindrops spawning wherever invisible particles from an emitter above an object collide with its mesh. But it looked pretty hard to get going.