org.j3d.geom.particle
Class PointEmitter

java.lang.Object
  org.j3d.geom.particle.BaseEmitter
      org.j3d.geom.particle.PointEmitter

All Implemented Interfaces:

ParticleInitializer

public class PointEmitter
extends BaseEmitter

Particle emitter that generates particles with an initial speed and direction from a single point in space.

Version:

$Revision: 2.0 $

Author:

Justin Couch

Field Summary

Fields inherited from class org.j3d.geom.particle.BaseEmitter

color, initialMass, lifetime, lifetimeVariation, particleCount, randomiser, speed, surfaceArea, variation

Constructor Summary

PointEmitter()
Construct a new default emitter.

PointEmitter(int maxTime, int maxParticleCount, float[] position, float[] direction, float[] color, float speed, float variation)
Construct a new emitter instance for a point emitter that gives the particle a random force direction and strength.

Method Summary

boolean	initialize(Particle particle) Initialize a particle based on the rules defined by this initializer.
int	numParticlesToCreate(int timeDelta) The number of particles that should be created and initialised this frame.
void	setDirection(float x, float y, float z) Change the initial velocity that the particles are endowed with by modifying the direction.
void	setMaxParticleCount(int maxCount) Adjust the maximum number of particles that this initializer is going to work with.
void	setParticleLifetime(int time) Change the maximum lifetime of the particles.
void	setPosition(float x, float y, float z) Change the basic position that the particles are being generated from.
void	setSpeed(float speed) Change the initial speed that the particles are endowed with.

Methods inherited from class org.j3d.geom.particle.BaseEmitter

getColor, getLifetimeVariation, getMass, getMaxParticleCount, getParticleLifetime, getParticleVariation, getSpeed, getSurfaceArea, setColor, setLifetimeVariation, setMass, setParticleVariation, setSurfaceArea

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PointEmitter

public PointEmitter()

Construct a new default emitter. All values are set to zero, and the direction is straight up along the Y axis.

PointEmitter

public PointEmitter(int maxTime,
                    int maxParticleCount,
                    float[] position,
                    float[] direction,
                    float[] color,
                    float speed,
                    float variation)

Construct a new emitter instance for a point emitter that gives the particle a random force direction and strength. The number of particles to create each frame is driven from the maximum particle count divided by the average lifetime.

Parameters:

maxTime - The time length of the particles to exist in milliseconds

maxParticleCount - The maximum number of particles to manage

position - The emitting position in the local space

direction - The emitting direction in the local space

speed - The initial color of particles (4 component)

variation - The amount of variance for the initial values

Method Detail

setMaxParticleCount

public void setMaxParticleCount(int maxCount)

Adjust the maximum number of particles that this initializer is going to work with. This should not normally be called by the end user. The particle system that this initializer is registered with will call this method when it's corresponding method is called.

Specified by:

setMaxParticleCount in interface ParticleInitializer

Overrides:

setMaxParticleCount in class BaseEmitter

Parameters:

maxCount - The new maximum particle count to use

setParticleLifetime

public void setParticleLifetime(int time)
                         throws java.lang.IllegalArgumentException

Change the maximum lifetime of the particles. The lifetime of particles is defined in milliseconds, and must be positive.

Specified by:

setParticleLifetime in interface ParticleInitializer

Overrides:

setParticleLifetime in class BaseEmitter

Parameters:

time - The new lifetime, in milliseconds

Throws:

java.lang.IllegalArgumentException - The lifetime is zero or negative

numParticlesToCreate

public int numParticlesToCreate(int timeDelta)

The number of particles that should be created and initialised this frame. This is called once per frame by the particle system manager. Sends all particles initialially and nothing after that.

Parameters:

timeDelta - The delta between the last frame and this one in milliseconds

Returns:

The number of particles to create

initialize

public boolean initialize(Particle particle)

Initialize a particle based on the rules defined by this initializer. The particle system may choose to re-initialise previously dead particles. The implementation should not care whether the particle was previously in existance or not.

Parameters:

particle - The particle instance to initialize

Returns:

true if the ParticleSytem should keep running

setPosition

public void setPosition(float x,
                        float y,
                        float z)

Change the basic position that the particles are being generated from.

Parameters:

x - The x component of the location

y - The y component of the location

z - The z component of the location

setSpeed

public void setSpeed(float speed)

Change the initial speed that the particles are endowed with.

Specified by:

setSpeed in interface ParticleInitializer

Overrides:

setSpeed in class BaseEmitter

Parameters:

speed - The magnitude of the speed to use

setDirection

public void setDirection(float x,
                         float y,
                         float z)

Change the initial velocity that the particles are endowed with by modifying the direction. Speed still stays the same. The direction value will be normalised to a unit length vector before being applied to the velocity calculation.

Parameters:

x - The x component of the velocity direction

y - The y component of the velocity direction

z - The z component of the velocity direction