public void reset(int index) {
if (systems == null) {
systems = new ParticleSystem[maxStep];
steps = new int[maxStep];
addVelocities = new Vector3[maxStep][particleSize];
}
if (systems[index] == null) { // initialize
Geometry geometry = THREE.Geometry();
for (int i = 0; i < particleSize; i++) {
geometry.vertices().push(THREE.Vector3(0, 0, 0));
}
ParticleSystem system = THREE.ParticleSystem(geometry, baseMaterial.build());
// system.setSortParticles(true);
systems[index] = system;
parent.add(system);
} else {
//
ParticleSystem system = systems[index];
((ParticleBasicMaterial) system.getMaterial()).setSize(baseSize);
for (int i = 0; i < particleSize; i++) {
Vector3 vertex = system.getGeometry().vertices().get(i);
vertex.set(0, 0, 0);
}
system.getGeometry().setVerticesNeedUpdate(true);
}
// addVelocities=new Vector3[maxStep][particleSize];
// simple and boring
for (int i = 0; i < particleSize; i++) {
addVelocities[index][i] =
THREE.Vector3(
plusMinus(velocityRange.getX()),
plusMinus(velocityRange.getY()),
plusMinus(velocityRange.getZ()));
}
Vector3 addwind =
THREE.Vector3(
plusMinus(velocityRange.getX()) * 2,
plusMinus(velocityRange.getY()) * 2,
plusMinus(velocityRange.getZ()) * 2);
// wind.addSelf(addwind);
if (index % 5 == 0) {
wind.set(
wind.getX() / 4 * 3 + addwind.getX() / 4,
wind.getY() / 4 * 3 + addwind.getY() / 4,
wind.getZ() / 4 * 3 + addwind.getZ() / 4);
}
for (int i = 0; i < particleSize; i++) {
winds[i] =
THREE.Vector3(
plusMinus(velocityRange.getX()) * 5,
plusMinus(velocityRange.getY()) * 5,
plusMinus(velocityRange.getZ()) * 5);
}
}
public void update() {
if (systems == null || systems[index] == null) {
reset(index);
}
for (int j = 0; j < maxStep; j++) {
ParticleSystem system = systems[j];
if (system == null) {
break;
}
Vector3 addAccel = THREE.Vector3(0, accel.getY() * steps[j], 0);
for (int i = 0; i < particleSize; i++) {
Vector3 vertex = system.getGeometry().vertices().get(i);
vertex.addSelf(velocity);
vertex.addSelf(addVelocities[j][i]);
vertex.addSelf(wind);
vertex.addSelf(addAccel); // do slow
// vertex.getPosition().addSelf(winds[i]);
}
system.getGeometry().setVerticesNeedUpdate(true);
((ParticleBasicMaterial) system.getMaterial()).setSize(baseSize + changeSize * steps[j]);
((ParticleBasicMaterial) system.getMaterial())
.setOpacity(Math.max(0, 1 - changeOpacity * steps[j]));
steps[j]++;
if (steps[j] == maxStep) {
reset(j);
steps[j] = 0;
}
}
index++;
if (index == maxStep) {
index = 0;
}
}