private void applyForces(final double dt) {
for (final Object object : this.particles.keySet()) {
final Particle particle = this.particles.get(object);
final Vector oldSpeed = particle.getSpeed();
final Vector newSpeed = oldSpeed.add(this.forces.get(object).scale(dt / particle.getMass()));
particle.setSpeed(newSpeed);
}
}
/**
* @see
* org.newdawn.slick.particles.ParticleEmitter#updateParticle(org.newdawn.slick.particles.Particle,
* int)
*/
@SuppressWarnings("null")
@Override
public void updateParticle(Particle particle, int delta) {
particleCount++;
// adjust the particles if required
particle.x += adjustx;
particle.y += adjusty;
particle.adjustVelocity(
windFactor.getValue(0) * 0.00005f * delta, gravityFactor.getValue(0) * 0.00005f * delta);
float offset = particle.getLife() / particle.getOriginalLife();
float inv = 1 - offset;
float colOffset = 0;
float colInv = 1;
Color startColor = null;
Color endColor = null;
for (int i = 0; i < colors.size() - 1; i++) {
ColorRecord rec1 = colors.get(i);
ColorRecord rec2 = colors.get(i + 1);
if ((inv >= rec1.pos) && (inv <= rec2.pos)) {
startColor = rec1.col;
endColor = rec2.col;
float step = rec2.pos - rec1.pos;
colOffset = inv - rec1.pos;
colOffset /= step;
colOffset = 1 - colOffset;
colInv = 1 - colOffset;
}
}
if (startColor != null) {
float r = (startColor.r * colOffset) + (endColor.r * colInv);
float g = (startColor.g * colOffset) + (endColor.g * colInv);
float b = (startColor.b * colOffset) + (endColor.b * colInv);
float a;
if (alpha.isActive()) a = alpha.getValue(inv) / 255.0f;
else
a = ((startAlpha.getValue(0) / 255.0f) * offset) + ((endAlpha.getValue(0) / 255.0f) * inv);
particle.setColor(r, g, b, a);
}
if (size.isActive()) {
float s = size.getValue(inv);
particle.setSize(s);
} else particle.adjustSize(delta * growthFactor.getValue(0) * 0.001f);
if (velocity.isActive()) particle.setSpeed(velocity.getValue(inv));
if (scaleY.isActive()) particle.setScaleY(scaleY.getValue(inv));
}
private void slowdownSpeeds(final double dt) {
for (final Object object : this.particles.keySet()) {
final Particle particle = this.particles.get(object);
final Vector oldSpeed = particle.getSpeed();
final double oldSpeedValue = oldSpeed.getLength();
final double newSpeedValue = this.slowdownFunction.evaluate(oldSpeedValue, dt);
final Vector newSpeed = oldSpeed.setLength(newSpeedValue);
particle.setSpeed(newSpeed);
}
}
