public void Emit()
{
TransformComponent myXForm = Owner.GetComponent <TransformComponent>(ActorComponent.ComponentType.Transform);
for (int i = 0; i < 20; ++i)
{
mParticleSystem.AddParticle(myXForm.Translation, Vector3.Zero);
}
GameResources.ActorManager.PreAnimationUpdateStep += PreAnimationUpdateHandler;
}
private void PreAnimationUpdateHandler(object sender, UpdateStepEventArgs e)
{
if (mTargetActorId == Actor.INVALID_ACTOR_ID)
{
if (!mParticleSystem.HasActiveParticles)
{
Owner.Despawn();
}
return;
}
// Work out how much time has passed since the previous update.
float elapsedTime = (float)(e.GameTime.ElapsedGameTime.TotalSeconds);
Vector3 newPosition = GetPosition();
if (elapsedTime > 0)
{
// Work out how fast we are moving.
Vector3 velocity = (newPosition - mPreviousPosition) / elapsedTime;
// If we had any time left over that we didn't use during the
// previous update, add that to the current elapsed time.
float timeToSpend = mTimeLeftOver + elapsedTime;
// Counter for looping over the time interval.
float currentTime = -mTimeLeftOver;
// Create particles as long as we have a big enough time interval.
while (timeToSpend > mTimeBetweenParticles)
{
currentTime += mTimeBetweenParticles;
timeToSpend -= mTimeBetweenParticles;
// Work out the optimal position for this particle. This will produce
// evenly spaced particles regardless of the object speed, particle
// creation frequency, or game update rate.
float mu = currentTime / elapsedTime;
Vector3 position = Vector3.Lerp(mPreviousPosition, newPosition, mu);
// Create the particle.
mParticleSystem.AddParticle(position, velocity);
}
// Store any time we didn't use, so it can be part of the next update.
mTimeLeftOver = timeToSpend;
}
mPreviousPosition = newPosition;
}
private void PreAnimationUpdateHandler(object sender, UpdateStepEventArgs e)
{
mParticleSystem.AddParticle(mTransform.Translation, Vector3.Zero);
}