Emitters are simply a way of releasing particles. They have several different shapes that the released particles can form. Mercury Particle Engine already has some predefined shapes out of the box, but you are free to create your own by using the base class
Emitters have several important properties that define the characteristics of the emitter. You can see a description of them right here:
This is one of the most important properties. You need to set the budget on all emitters to tell them how many active particles they can have. If you set this to 1000, the emitter can't have more than 1000 active particles at one time.
This defines the quantity of particles released. Whenever you update the particle engine some particles will be released; this amount is defined by the value you set ReleaseQuantity to. With a budget of 3000 and a ReleaseQuantity of 10, you will get a light
steady stream of particles; you can control the density of the particles by having a higher ReleaseQuantity.
This is used to tell the emitter how long the released particles will stay active. Most particles will fade away after some time and thus we need a mechanism for keeping track of active particles. Term combined together with age (on each particle) is essentially
Particles need some sort of shape and texture. You could just do with a single pixel, but to get more complex and real particle simulation, you will need a shape and texture. This property defines the texture applied to the particles.
This is also one of the more important ones. We will describe modifiers later in its own chapter. This property is a collection of the working modifiers on the emitter.
We also have ReleaseSpeed, ReleaseColour, ReleaseOpacity, ReleaseScale and ReleaseRotation. They all control the initial properties of the particle when it's released.