Executing code every tick and saving global data

[Anrza]

Hello! I am looking to have a global time variable that ticks up with the normal gameTick but skips forward when you use the time command or skip the night by sleeping, in order to simulate the time that has passed. Quite confident with the logical part of it, but I have a few questions regarding how to save/sync and properly update every tick:

1. What is the proper way to run code every tick? I've looked at listening for TickEvent or ClientTickEvent and ServerTickEvent. Would it be sensible to use them?
2. How do I save global data on the server? The documentation is somewhat useful, but it's outdated and I haven't found a way to save global data.
3. How do I conveniently send time data from server to client? Should I use my own packets? Can I include the numbers when sending initial world data to the client?
4. Can I count on World#getGameTime and World#getDayTime to stay in sync between server and client? If so, I should be able to just execute the same code every tick on both client and server to keep them in sync.
5. Can I count on World#getGameTime and World#getDayTime to be equal across different worlds on the server? From my testing, they seem to be the same regardless of which world you call the method from.

Thanks in advance for any answers to my questions!

[Alpvax]

1,2: It depends exactly what you are after. I would recommend using WorldTickEvent, and saving the time in a capability attached to the world. If you want to track each dimension independently, use the specific world#getGameTime, otherwise just use the overworld (using specific worlds the time will only increment when the world is loaded).

1&2: I would suggest listening to ServerTickEvent (with Phase END), and keeping the data attached to a capability attached to the Overworld. you can get the time using overworld#getGameTime. To keep track of time sleeping, subscribe to SleepFinishedTimeEvent (at EventPriority.LOWEST to run after all other listeners) and add the time difference.

3: packets, it depends what you need on the client. If it is just for rendering in a GUI, you could use a containerscreen to sync it, otherwise I believe you will need packets (sent whenever the offset between gametime and your gametime + sleeptime changes.

4: Yes, but the sleep event is only fired on the server, so you will have to manually sync your offset.

5: Yes, all worlds other than the Overworld use a DerivedWorldInfo, which just passes both times through from the overworld info. (I didn't realise this until I just looked).

[poopoodice]

Just a thought, instead having your own timer, you can have an "extra time" where when the night skips you add it by xx value...or something similar, and when you need that specific value you just get it by adding it with the current game time.

Edited July 15, 2021 by poopoodice

[Anrza]

@Alpvax

Thanks for your answers!

For the record, I'm not listening for any sleep events. Since AFAIK it's not fired if time is set by a command, I'm using a more general approach.

@poopoodice

Thanks for your reply! I am indeed looking to use an offset variable. It's a good point that I shouldn't have to store any other time variable, and I'll look into that.

[Alpvax]

  On 7/16/2021 at 2:00 PM, Anrza said:

@Alpvax

Thanks for your answers!

For the record, I'm not listening for any sleep events. Since AFAIK it's not fired if time is set by a command, I'm using a more general approach.

@poopoodice

Thanks for your reply! I am indeed looking to use an offset variable. It's a good point that I shouldn't have to store any other time variable, and I'll look into that.

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The `dayTime` value is set by the command, so you could listen for the command event, check the daytime before, subtract it from the daytime after (wait 1 tick to get the "after" time) and add that difference to your offset if you wanted. It depends how accurate you want to be.

Alternatively, when your offset changes, you could check the difference between `gameTime` and `dayTime` (you would then have to track a second offset to check when it changes, but it might give you a bit more accuracy).

 

  On 7/15/2021 at 2:26 PM, Alpvax said:

offset between gametime and your gametime + sleeptime

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I meant that you should just save the offset, as poopoodice suggested