What I would like is some control over particle direction of movement.
For example, it would be nice to have some kind of "force emitter" that would add forces to the particles as they get closer to it.
Even better, it would be cool to have some kind of programmed control over the movement of the particle, like a callback function or something that the particle system can use when updating particle state.
I'm not sure what you ask but it look like vanilla unity particle system look here:
http://unity3d.com/support/documentation/Manual/Particle%20Systems.htmlhttp://unity3d.com/support/documentation/ScriptReference/ParticleEmitter.htmlhttp://unity3d.com/support/documentation/ScriptReference/Particle.htmlParticle Collider
The World Particle Collider is used to collide particles against other Colliders in the scene.
A Particle System colliding with a Mesh Collider
Properties
Bounce Factor Particles can be accelerated or slowed down when they collide against other objects. This factor is similar to the Particle Animator's Damping property.
Collision Energy Loss Amount of energy (in seconds) a particle should lose when colliding. If the energy goes below 0, the particle is killed.
Min Kill Velocity If a particle's Velocity drops below Min Kill Velocity because of a collision, it will be eliminated.
Collides with Which Layers the particle will collide against.
Send Collision Message If enabled, every particle sends out a collision message that you can catch through scripting.
Developer
