Particle System Emitters

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General Operations

Operator Fade In/Fade Out/Fade Oscillate - These are standard operators that work on continuous emitters. Currently they do not fade in and out, but this will work eventually.

In and Out times are relative to the emitter lifespan, so an emitter that fades in after 3 seconds does so relative to the emitters life, not any given individual particle.

If an oscillation time is set, fade in and fade out times become 0.0 to 1.0 times relative to that oscillation time. That is if you wish your emitter to oscillate in and out, setting an oscillation time of 4, a fade in of .25 and a fade out of .75 would mean that the emitter has no effect for 1 second (one quarter the oscillation cycle time), works for 2 seconds (.25-.75), fades back out at 3 (three quarters of the oscillation cycle time), and then the cycle loops at the 4th second back to the start.


emit_instantaneously

Emits particles in one instantaneous burst.

emission_start_time
Time at which to begin emitting particles (seconds).
num_to_emit
Number of particles to emit in a burst.
num_to_emit_minimum
The minimum number of particles to emit in a burst. Any value other than -1 will tell the system to randomly emit a number of particles between this value and the num_to_emit value.
maximum emission per frame
The maximum number of particles to emit per frame. For example, if the game is running at 30 frames per second and this value is set to 1, then 30 particles will be emitted in one second. Keep in mind that even though the particles are emitted at a different time, they will all die together at the same time. Therefore, if lifetime random is set to 2, then every particle regardless of when it was created will be removed after 2 seconds of the system's lifetime.

emit_continuously

Emits particles continuously over a specified period of time.

emission_start_time
Time at which to begin emitting particles (seconds).
emission_rate
Number of particles to spawn (per second).
emission_duration
Length of time to continue emitting particles (seconds).

emit noise

Emits particles over a specified period of time using Perlin noise.

emission_start_time
Time at which to begin emitting particles (seconds).
emission_duration
Length of time to continue emitting particles (seconds).
scale emission to used control points
Which control point should be used (integer).
time noise coordinate scale
How much should time be scaled for noise? (seconds)
For example, a value of 0.1 "changes" between the maximum value and minimum value every 10 seconds, a value of 1 changes every second, a value of 10 changes every 0.1 seconds, etc.
time coordinate offset
The value at which to offset the time coordinate. (float)
absolute value
Only pick out absolute values (positive values) from the noise? (boolean)
(bias towards the emission minimum due to only picking highest values to emit particles)
invert absolute value
Only pick out inverted absolute values (negative values) from the noise? (boolean)
(bias towards the emission maximum due to only picking lowest values to emit particles)
emission minimum
Minimum amount of particles to emit. (float)
emission maximum
Maximum amount of particles to emit. (float)
world time noise coordinate scale
How much should time be scaled for noise relative to world? (float)