Particle System not starting immediately

I'm looking to get my particle system to start immediately upon Play(). I have the Start Delay set to 0, but there's a delay - I've set its Emission->Rate Over Time as 8 (for an automatic gun), but it doesn't start until the the first interval. In this case, the first particle emits at 0, plus (I'm guessing here) one second divided by the number of shots per second, so the first particle is visible at roughly .125 seconds from the time its Play() method is called.

So, how do I fix this to start immediately?

 

https://docs.unity3d.com/ScriptReference/ParticleSystem.MainModule-prewarm.html



Try the prewarm setting, I think that does it.

 

That bumps it up to at least 21 particles immediately, which isn't my desired effect for a gun. It also has them starting away from the source. By using prewarm, you'd think it might generate the first 8 immediately and then work the way it was intended, so I don't know why the number is so high.

 

If you're going for poofs of smoke as rounds are fired, you might want to set its emission to zero and then call the .Emit() method on it periodically to poof out some smoke. That should be instantaneous.

 

T

Thank you, it looks like it was as simple as that - calling Emit() with one particle, followed by Play().

 

Sweet! I think the .Play() call is not needed, as long as the ParticleSystem is already playing.

Reason: I have emitted a particle or two in my career.

 

I actually called it with quite a few particles and made them very translucent for this effect:

 

This worked great for me, I wish they would have this as part of the control but maybe this has something to do with making your own systems. However this did work on Asset Store system's that I didn't create. So

private ParticleSystem instantiate(ParticleSystem prefab, Vector3 position)
{

//https://forum.unity.com/threads/particle-system-not-starting-immediately.1075693/
ParticleSystem newParticleSystem = Instantiate(prefab,position,Quaternion.identity) as ParticleSystem;
newParticleSystem.Emit(1);
/// -----------------------------
// Make sure it will be destroyed
/// -----------------------------
/// https://stackoverflow.com/questions/41393814/unity-5-5-obsolete-particle-system-code
Destroy(
newParticleSystem.gameObject,
newParticleSystem.main.duration
);

return newParticleSystem;
}

Thanks to Creepy Cat
3D Games Effects Pack Free
3D Games Effects Pack Free | VFX Particles | Unity Asset Store
for the starter script..

Also Added Sound and the time the system is done.

Full Edited

using UnityEngine;

/// ------------------------------
/// Creating instance of particles
/// ------------------------------
///
[RequireComponent(typeof(AudioSource))]
public class InstanceExample : MonoBehaviour
{
/// ------------------------------
/// Singleton
/// ------------------------------
public static InstanceExample Instance;
public ParticleSystem effectA;
public ParticleSystem effectB;
private AudioSource Audio = null;

void Awake()
{
/// ---------------------
// Register the singleton
/// ---------------------
if (Instance != null)
{
Debug.LogError("Multiple instances of InstanceExample script!");
}

Instance = this;

Audio = gameObject.GetComponent<AudioSource>();
Audio.playOnAwake = false;
/// https://stackoverflow.com/questions/41393814/unity-5-5-obsolete-particle-system-code
ParticleSystem.MainModule main = effectB.main;
//Stops Loops if there is one.
main.loop = false;

}

void Update(){

if (Input.GetKeyDown(KeyCode.Space))
{
/// -----------------------------------------
/// Instanciate into a box of 5 x 5 x 5 (xyz)
/// -----------------------------------------
InstanceExample.Instance.Explosion(new Vector3(Random.Range(-5.0f, 5.0f), Random.Range(-5.0f, 5.0f), Random.Range(-5.0f, 5.0f)));

if (Audio.clip != null)
{
Audio.Play();
}
}

}

/// -----------------------------------------
/// Create an explosion at the given location
/// -----------------------------------------
public void Explosion(Vector3 position)
{
instantiate(effectA, position);
instantiate(effectB, position);
}

/// -----------------------------------------
/// Instantiate a Particle system from prefab
/// -----------------------------------------
private ParticleSystem instantiate(ParticleSystem prefab, Vector3 position)
{

//https://forum.unity.com/threads/particle-system-not-starting-immediately.1075693/
ParticleSystem newParticleSystem = Instantiate(prefab,position,Quaternion.identity) as ParticleSystem;
newParticleSystem.Emit(1);
/// -----------------------------
// Make sure it will be destroyed
/// -----------------------------
Destroy(
newParticleSystem.gameObject,
newParticleSystem.main.duration
);

return newParticleSystem;
}

}

 

Thanks for posting this, but it would work even greater for everybody else if you went back and formatted your code properly so it isn't a wall of incomprehensible text barf for the future to suffer.

If you post a code snippet, ALWAYS USE CODE TAGS:

How to use code tags: https://forum.unity.com/threads/using-code-tags-properly.143875/

 

For anyone else coming across this, I was able to solve the issue by using a single count "Burst" emission rather than "Rate over Time" in the Emission module.

 

This worked for me, thank you!

 

Thank you

 

Thank you men!I couldn't decide that problem in my game for a long time.But now thanks to you i can to do this!The Emit() method is similar to the WakeUp() from Rigidbody