Package tripleplay.particle.effect

Class Gravity

java.lang.Object

tripleplay.particle.Effector

tripleplay.particle.effect.Gravity

public class Gravity
extends Effector

Applies uniform gravity to particles.

Field Summary

Fields

Modifier and Type	Field	Description
static final float	EARTH_G	Earth gravity.

Constructor Summary

Constructors

Constructor	Description
Gravity()	Creates a gravity effector with earth equivalent gravity.
Gravity(float accel)	Creates a gravity effector.

Method Summary

Modifier and Type	Method	Description
void	apply(int index, float[] data, int start, float now, float dt)	Applies this effector to the indexth particle in the supplied buffer.

Methods inherited from class java.lang.Object

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

Field Details

EARTH_G

public static final float EARTH_G

Earth gravity.

See Also:

• Constant Field Values

Constructor Details

Gravity

public Gravity()

Creates a gravity effector with earth equivalent gravity.

Gravity

public Gravity(float accel)

Creates a gravity effector.

Parameters:

accel - the constant acceleration to apply to the y velocity of a particle. Positive accelerates the particle toward the bottom of the screen.

Method Details

apply

public void apply(int index,
 float[] data,
 int start,
 float now,
 float dt)

Description copied from class: Effector

Applies this effector to the indexth particle in the supplied buffer. The effector must use the ParticleBuffer offsets to extract fields from data, for example: float x = data[start+ParticleBuffer.POS_X].

Specified by:

apply in class Effector

Parameters:

index - the index of the particle, which can be used to index into other per-particle data arrays.

data - the particle field data.

start - the offset into data at which the particle's fields start.

now - the number of seconds elapsed since the emitter came into being. Can be used to compute a particle's age.

dt - the amount of time (in fractions of a second) that has elapsed since the last update.