ParticleEmitter

ParticleEmitter derives from BillboardSet to implement a particle system that updates automatically. Defined in the [Engine] library.

The particle system's properties can be set through a XML description file.

Most of the parameters can take either a single value, or minimum and maximum values to allow for random variation. Where available, the example below demonstrates setting both the minimum and maximum:

 <particleemitter>
   <material name="ParticleMaterial.xml" />
   <sorting enable="true|false" />
   <updateinvisible enable="true|false" />
   <relative enable="true|false" />
   <emittertype value="point|box|sphere" />
   <emittersize value="x y z" />
   <direction min="x1 y1 z1" max="x2 y2 z2" />
   <constantforce value="x y z" />
   <dampingforce value="x" />
   <activetime value="t" />
   <inactivetime value="t" />
   <interval min="t1" max="t2" />
   <particlesize min="x1 y1" max="x2 y2" />
   <timetolive min="t1" max="t2" />
   <velocity min="x1" max="x2" />
   <rotation min="x1" max="x2" />
   <rotationspeed min="x1" max="x2" /> 
   <sizedelta add="x" mul="y" />
   <color value="r g b a" />
   <colorfade color="r g b a" time="t" />  
 </particleemitter>

Note: zero active or inactive time period means infinite. Instead of defining a single color element, several colorfade elements can be defined in time order to describe how the particles change color over time.