I want to attach a particle emitter to a bird that flies around in my scene - I want the particles to be of random size within a tolerance, and fall as if they were effected by gravity. What is the simplest way to do this?
I read the particles page but didn’t see any mention of gravity or of randomizing values other than added velocity.
The “Min Size” and “Max Size” fields on particle emitters handle the random size (with tolerances for you). See the particle emitter documentation here. As for having them fall, you’d set the force on the Particle Animator to be the same as your gravity. If the object that’s dropping the particles is moving, you may or may not want to set the World Velocity in the emitter to match the object’s velocity, depending on how you want it to look. For example, bird droppings would start out with the same velocity as the bird, but sometimes spaceship trails/magic effects look more interesting dropping straight down.