Hi all,
I'm trying to make a ghost who only appears during a few hours at night, patrols between some markers, and disappears in the morning.
Is there an "easy" way to activate/deactivate NPC on a schedule ?
Thanks!

I'm not sure if you can do this in an AI Package (which has a schedule). Anyway scripts are useful, as always. There seems to be a cool function http://www.creationkit.com/WaitGameTime_-_Utility. So I would create a quest script that would go like this:

Wow thanks. As i'm nowhere near beginning to understand this kind of scripting, i'll need time to carefully break down your example, but i'm sure it'll help me to find a general lead.
Thanks a lot anyway.

The CritterSpawn script implements a similar kind of timer. Here are the code sections that help CritterSpawn decide whether it's the right time to be actively spawning critters. The Critter script (or individual critter scripts like critterMoth seem to handle despawning critters when needed), but I haven't looked at those as much.... Hope this helps!

GlobalVariable property GameHour auto{ Make this point to the GameHour global }float property fStartSpawnTime = 6.0 auto{ The Time after which this spawner can be active}float property fEndSpawnTime = 11.0 auto{ The Time before which this spawner can be active}

bool Function IsActiveTime()	  bool binTimeRange = false	  if (fEndSpawnTime >= fStartSpawnTime)  			  binTimeRange = (GameHour.GetValue() >= fStartSpawnTime) && (GameHour.GetValue() < fEndSpawnTime)	  else			  binTimeRange = (GameHour.GetValue() >= fStartSpawnTime) || (GameHour.GetValue() < fEndSpawnTime)	  endIf	  ; this script also takes into account weather conditions - Ashs	  return binTimeRange && ((Weather.GetCurrentWeather() == none) || (Weather.GetCurrentWeather().GetClassification() < 2) || (bSpawnInPrecipitation == TRUE))endFunction

Ashs, this is great! I didn't know about this GameHour global. So I'm pasting an updated version of my script (note that I made a mistake previously, writing: "Property Actor" when it should be "Actor Property"). I can't know for sure whether it will work or not, so you've got to try yourself.

Scriptname GhostScript extends QuestActor Property Ghost  Autoint i = 0GlobalVariable Property GameHour Autoauto State Initialization    Event OnInit()        Registerforupdate(300)    EndEvent    Event OnUpdate()        if GameHour.GetValue() >= 24.0 ; It's possible that it should be value 0.0. You could also just say 23 and be safe.            UnregisterForUpdate()            GoToState("Schedule")        endif    EndEventEndStateState Schedule    Event OnInit()        while i >= 0            Ghost.enable()            WaitGameTime(5)            ; The script now pauses for 5 in-game hours.            Ghost.disable()            WaitGameTime(19)            i = i + 1            ; After pausing for 19 hours the script will go from the beggining,            ; enabling the ghost, then waiting, disabling him and so on.        endwhile    EndEventEndState

Thanks to you two!
Now, keep in mind i've actually zero experience in the scripting field, so don't be surprised if i try/say silly things I added Universal's script to my quest scripts tab, and the compilation returns the following errors :

(8,4): function oninit cannot be defined in state initialization without also being defined in the empty state(24,12): WaitGameTime is not a function or does not exist(27,12): WaitGameTime is not a function or does not exist(21,4): function oninit cannot be defined in state schedule without also being defined in the empty state

Did i miss something ? Or maybe there is actually some mistake in the script ? Thanks anyway !

Those were my mistakes. Try this:

Might be easier with two states:

State GhostOn    Event OnBeginState()        Ghost.enable()        Utility.WaitGameTime(5)        GoToState("GhostOff");    EndEventEndStateState GhostOff    Event OnBeginState()        Ghost.disable()        Utility.WaitGameTime(19)        GoToState("GhostOn");    EndEventEndState

Well, maybe the first part of my script should be in a state after all and then "OnInit()" should be replaced with "OnBeginState()"... But DocClox, what you're forgetting is that you can't just enable the ghost at any hour. You must first check if the starting hour is right, THEN create a "schedule" script.

I thought onBeginState didn't trigger in the empty state? Which isn't to say Papyrus might not want it defined, I suppose.


Sure. All you do is enter GhostOn state at midnight instead of Schedule Then it should work the same way.

Heh, now I'm not sure whether you read what I wrote wrong or vice versa.

I said that the first part of my script should be in a state, call it Initialization like in my first attempt to script this. So "RegisterForUpdate(300)" would be inside "Event OnBeginState()" and it would be inside "auto State Initialization". I believe it would work then.

Can you do that? Hm, I guess you can... But you know, then Lemsama could just create an AI Package with schedule set to begin in the evening and end, say, 5 hours later, and with scripts in the Begin and End Papyrus fragments that would be just "Ghost.Enable" and "Ghost.Disable".

So I guess some things are just possible to accomplish in a multitude of ways.

For another example you could look at the headless horseman actor and see what is done to make him only show up at night.

Well, I tried Universal's corrected script, I tried the script using DocClox states instead of the original schedule, I even tried to put the script in the AI Package fragments as Universal suggested. It seems i'm not able to make anything work
There's probably something wrong on my side. Oh well, i guess i still lack more basic knowledge to make use of your generous help Anyway, thanks to you all, i still learned useful things, and i will keep trying.

@Riakon : Yup, it's the first thing i checked before starting this, but i'm afraid i couldn't find any leads when i looked at this actor, his quest, scripts, etc. Thanks for the idea!

I'm a little surprised that none of the methods suggested worked... If it returns any errors on compilation, copy/paste them. Anyway, good luck and sorry that my advices didn't help. Learn and try to make it work and if you have any specific problem, just write.

Sure. I didn't mean to suggest there was anything wrong with your approach. I just suggested using two states because it cleaned the logic up a little.

Of course, none of this matters if the thing doesn't work at all. I should have access to my CK instance tonight. I might see what I can do with that.

Hey, Doc, no problem! I'm not so easily offended.

Actually, there are no compilation errors. That's why i guess the issue is certainly on my side. I think the script is fine, but i may not trigger it properly. I don't really know if I should put it in the quest scripts, in the alias scripts, in the actor scripts, ... I tried it all actually, but even then, i'm not sure if i need to do something more to trigger it correctly, and if the actor should be checked as "initially disabled".
My brain is melting ! (I'm sure tomorrow i'll realize i was just missing a stupid single obvious thing)

It should be in quest scripts, the quest should be running and you may want to wait a little in-game time, like 24 hours, to get the script started and then just wait till evening.

One of the points in the notes section of that page is How reliable is this function? How much longer would the wait be if the player fast traveled?