org.j3d.geom.particle
Class Particle

java.lang.Object
  org.j3d.geom.particle.Particle

public abstract class Particle
extends java.lang.Object

An abstract Particle that defines some physical properties and life-cycle properties.

This class is subclassed for specific types of particle that have a means of representing themselves. This class contains some fields commonly used to implement physics based particle systems, such as force, energy, surface area as well as a total age and a cyclable age.

Particles start with all settings as zero, except the dimensions, which default to 0.2.

Version:

$Revision: 2.0 $

Author:

Justin Couch, Daniel Selman

Field Summary

protected float	alpha Red component of the color of the particle
protected float	blue Blue component of the color of the particle
protected float[]	boundingBox bounding box for the particle
protected int	cycleAge a resettable cyclable age
protected float	depth depth of the particle
protected float	energy currently unused and undefined
protected float	green Green component of the color of the particle
protected float	height height of the particle
protected float	mass Mass of the object in kilograms
protected int	particleLife The maximum lifetime of this particle in milliseconds
protected javax.vecmath.Point3f	position Current position of the particle
protected float	red Red component of the color of the particle
protected javax.vecmath.Vector3f	resultantForce Force applied to the particle in newtons
protected float	surfaceArea Surface area of the particle in square meters
protected javax.vecmath.Vector3f	velocity Current velocity in meters per second
protected long	wallClockBirth The age of the particle in wall clock time (milliseconds), in this cycle
protected long	wallClockLife The end time in wall clock time (milliseconds)
protected float	width width of the particle in meters

Constructor Summary

Particle()
Construct a new particle instance.

Method Summary

long	getBirthTime() Get the wall clock time that this particle was born.
float[]	getBounds() Retrieve the bounds of this particle in local coordinate space.
void	getColor(float[] val) Retrieve the current colour that this particle has.
int	getCycleAge() Get the set maximum cycle age.
int	getCycleTime() Get the set maximum cycle time.
float	getDepth() Get the current depth of the particle.
float	getHeight() Get the current height of the particle.
float	getMass() Gets the mass of this particle.
void	getPosition(float[] val) Retrieve the current position of this particle.
javax.vecmath.Vector3f	getResultantForce() Gets the resultantForce applied to a particle.
float	getSurfaceArea() Gets the surfaceArea of the particle.
javax.vecmath.Vector3f	getVelocity() Gets the current velocity of the particle.
float	getWidth() Get the current width of the particle.
void	incAge() Increment the cycle age.
void	setColor(float r, float g, float b, float alpha) Set this particle to a new colour.
void	setCycleAge(int age) Set the cycle age to a new value.
void	setCycleTime(int time) Set the cycle time to a new value.
void	setDepth(float depth) Sets the depth of the particle.
void	setHeight(float height) Sets the height of the particle.
void	setMass(float mass) Sets the mass of this particle.
void	setPosition(float x, float y, float z) Set the new position of this particle.
void	setResultantForce(javax.vecmath.Vector3f force) Sets the resultantForce applied to a particle.
void	setSurfaceArea(float surfaceArea) Sets the surfaceArea.
void	setVelocity(javax.vecmath.Vector3f velocity) Sets the velocity of the particle.
void	setWidth(float width) Sets the width of the particle.

Methods inherited from class java.lang.Object

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

Field Detail

cycleAge

protected int cycleAge

a resettable cyclable age

wallClockBirth

protected long wallClockBirth

The age of the particle in wall clock time (milliseconds), in this cycle

wallClockLife

protected long wallClockLife

The end time in wall clock time (milliseconds)

particleLife

protected int particleLife

The maximum lifetime of this particle in milliseconds

surfaceArea

protected float surfaceArea

Surface area of the particle in square meters

energy

protected float energy

currently unused and undefined

mass

protected float mass

Mass of the object in kilograms

resultantForce

protected javax.vecmath.Vector3f resultantForce

Force applied to the particle in newtons

velocity

protected javax.vecmath.Vector3f velocity

Current velocity in meters per second

position

protected javax.vecmath.Point3f position

Current position of the particle

boundingBox

protected float[] boundingBox

bounding box for the particle

red

protected float red

Red component of the color of the particle

green

protected float green

Green component of the color of the particle

blue

protected float blue

Blue component of the color of the particle

alpha

protected float alpha

Red component of the color of the particle

width

protected float width

width of the particle in meters

height

protected float height

height of the particle

depth

protected float depth

depth of the particle

Constructor Detail

Particle

public Particle()

Construct a new particle instance. The dimensions default to 0.2 but no surface area or mass.

Method Detail

getPosition

public void getPosition(float[] val)

Retrieve the current position of this particle.

Parameters:

val - An array of length 3 to copy the values to

setPosition

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

Set the new position of this particle.

Parameters:

x - The x coordinate of the new position

y - The y coordinate of the new position

z - The z coordinate of the new position

getColor

public void getColor(float[] val)

Retrieve the current colour that this particle has.

Parameters:

val - An array of length 4 to copy the values to

setColor

public void setColor(float r,
                     float g,
                     float b,
                     float alpha)

Set this particle to a new colour.

Parameters:

r - The red component of the colour

g - The green component of the colour

b - The blue component of the colour

alpha - The alpha component of the colour

getBounds

public float[] getBounds()

Retrieve the bounds of this particle in local coordinate space. They are widht, height, depth in order, first for lower bounds and upper bounds

Returns:

The array of bounding information

incAge

public void incAge()

Increment the cycle age.

getCycleAge

public final int getCycleAge()

Get the set maximum cycle age.

Returns:

The cycle age in frames

setCycleAge

public void setCycleAge(int age)

Set the cycle age to a new value.

Parameters:

age - The new age to set

getCycleTime

public final int getCycleTime()

Get the set maximum cycle time.

Returns:

The cycle time in frames

getBirthTime

public final long getBirthTime()

Get the wall clock time that this particle was born.

Returns:

The birth time in milliseconds

setCycleTime

public void setCycleTime(int time)

Set the cycle time to a new value.

Parameters:

time - The new time to set

getMass

public final float getMass()

Gets the mass of this particle.

Returns:

Returns a double

setMass

public void setMass(float mass)

Sets the mass of this particle.

Parameters:

mass - The mass to set

getResultantForce

public javax.vecmath.Vector3f getResultantForce()

Gets the resultantForce applied to a particle.

Returns:

Returns a Vector3d

setResultantForce

public void setResultantForce(javax.vecmath.Vector3f force)

Sets the resultantForce applied to a particle.

Parameters:

force - The resultant Force to set

getSurfaceArea

public final float getSurfaceArea()

Gets the surfaceArea of the particle.

Returns:

Returns a double

setSurfaceArea

public void setSurfaceArea(float surfaceArea)

Sets the surfaceArea.

Parameters:

surfaceArea - The surfaceArea to set

getVelocity

public javax.vecmath.Vector3f getVelocity()

Gets the current velocity of the particle.

Returns:

Returns a Vector3d

setVelocity

public void setVelocity(javax.vecmath.Vector3f velocity)

Sets the velocity of the particle.

Parameters:

velocity - The velocity to set

setDepth

public void setDepth(float depth)

Sets the depth of the particle.

Parameters:

depth - The depth to set

setHeight

public void setHeight(float height)

Sets the height of the particle.

Parameters:

height - The height to set

setWidth

public void setWidth(float width)

Sets the width of the particle.

Parameters:

width - The width to set

getWidth

public final float getWidth()

Get the current width of the particle.

Returns:

The current width value

getHeight

public final float getHeight()

Get the current height of the particle.

Returns:

The current height value

getDepth

public final float getDepth()

Get the current depth of the particle.

Returns:

The current depth value