Particle emitters...

I want to stop a particle emitter emitting just after it has fired one shot. At the moment I am it doing via

Code (csharp):

1.  
2. var lifeTime = 3.0;
3. var startTime = 0.0;
4.  
5. function Awake(){
6.     startTime = Time.time;
7.     }
8. function Update () {
9.    
10.     if (Time.time - startTime > lifeTime) {
11.         gameObject.particleEmitter.emit = false;
12.     }
13. }

but I have to hand tweak the lifeTime to stop the emmision between "shots" - is there a better way to stop emission after one shot?

thanks,
Richard.

PS The emitter is being spawned at some unknown time.

 

If you enable 'oneshot', all particles will spawn at the same time, and no other particles will be spawned before some of them die.

This should give you plenty of room.

Do something like:

Code (csharp):

1.  
2. var lifeTime = 3.0;
3. var startTime = 0.0;
4.  
5. function Awake(){
6.    startTime = Time.time;
7.    // Call the stopme function halfway before the minimum
8.    //energy of the particles are spent. This is a good margin.
9.    Invoke ("StopMe", particleEmitter.minEnergy * .5F);
10.    }
11.  
12. function StopMe () {
13.   particleEmitter.emit = false;
14. }
15.  

A few points:
* Instead of checking every frame if you've spent too much time, it is a bit faster to just use Invoke to get a call a bit later in time
* You don't need gameObject.particleEmitter - particleEmitter will do - saves a bit of typing.

Hope this helps.

 

Excellent - just the type of tips I need - many thanks.

On a similar note, I want to re-activate the game object a random time after it has been de-activated (by a user mouseDown). So, at the momnet I was thinking to again check every frame to see if the random time interval has passed - is there a better way of doing this sort of thing.

thanks again,
Richard.

 

Actually, when you deactivate the GO, the script no longer gets update calls.

I _think_ you can still use Instantiate, though....

sth. like:

Code (csharp):

1.  
2. function OnMouseDown () {
3.    Invoke ("WakeMe", 3); // Wake me up again in 3 seconds
4.    gameObject.active = false;
5. }
6.  
7. function WakeMe () {
8.   gameObject.active = true;
9. }
10.  

 

I checked through the docs after your previous suggestion and tried the coroutine thing:

Code (csharp):

1.  
2. var mushRoomPuffParticles : GameObject;          
3.  
4.  
5. function Update () {  
6. }    
7.  
8. function OnMouseDown(){
9.     if (Input.GetMouseButtonDown (0) ) {  
10.       var  mr : GameObject = Instantiate (mushRoomPuffParticles, transform.position, Quaternion.FromToRotation (Vector3.fwd, transform.position));
11.     }  
12.      mr.particleEmitter.emit = true;
13.      gameObject.active = false;  
14.      var rndTime =  Random.Range(2.0,4.0);
15.      StartCoroutine("reactivateMushroom",rndTime);
16. }
17.  
18. function reactivateMushroom(time){
19.    
20.     yield new WaitForSeconds (time);
21.     gameObject.active = true;
22.    
23. }  

Seems to work beautifully!

thanks again,
Richard.

 

Mmmm... not quite so well - I have to destroy all the emitters that are Instantiated!

R.

 

Simple - just make 'mr' a local variable, so you can get to it later.

 

Hi Joachim,
Eerr it doesn't seem to work. I have "one shot" and "autodestruct" switched on. In the Game view I turn on Play, but the emitter just keeps shooting away.

Richard.

thanks,
Richard.

 

Sorry - I must be missing something, but how do I stop the emission of particles? If I switch off emit (ie = false) then all the particles disappear. If I set the min and max energy to zero, then emission stops - is that what I am suposed to do?

many thanks,
Richard.

 

What you say is what happens - I am not sure what I was doing wrong previously. Thanks very much for your help - Richard.