static void InitTime(EntityManager mgr, float deltaTime, Range lifetime, NativeArray <Entity> newParticles)
{
// The time is evenly distributted from 0.0 to deltaTime.
// The time of each subsequent particle will be increased by this value.
// particle.time[0..n] = (0 * timeStep, 1 * timeStep, 2 * timeStep, ..., n * timeStep).
float timeStep = newParticles.Length > 1 ? (deltaTime / (float)(newParticles.Length - 1)) : 0.0f;
// We need to subtract deltaTime from the particle's relative time, because later in
// the same frame we are adding deltaTime to the particle's relative time when we process
// them. This ensures that the first, newly created particle will start at a relative time 0.0.
float time = -deltaTime;
foreach (var particle in newParticles)
{
var cParticle = mgr.GetComponentData <Particle>(particle);
cParticle.lifetime = ParticlesUtil.RandomRange(lifetime);
cParticle.time = time;
time += timeStep;
mgr.SetComponentData(particle, cParticle);
}
}
