How to save capability data?

[k-off]

I want my capability data to persist between deaths, dimensions, and when the player exits the game and returns but I'm confused as to how it works. I already have everything set up and my Mana capability works so that if the player falls, it will absorb damage. Then it regenerates after some time. However, while it's doing so, if I exit the game and return, the mana is automatically filled up because every variable is reset when the player rejoins the world. I do this in the player joining world event.

 

But where should I be retreiving this data when the player rejoins? If I set all my capability's mana variables when the object is created, how is it supposed to remember them if the player exits the world?

 

I can confirm that indeed my write and read nbt methods are called, and the data I print in writenbt are correct. It's just that when I reload the game, the value printed in readnbt is the default value 0, that's set in the constructor.

Edited May 22, 2020 by k-off

[ChampionAsh5357]

For death persisting and changing between dimensions, you should probably read over the forge documentation and look at some implementations (credits to Choonster). As for the data when the player joins, if the data is being reset to zero (assuming your write method is correct), then your error probably comes from incorrectly reading the values back. Another error I can think of has to do with logical sides, but this would have to deal with synchronization issues depending on how you call and read the information given.

[k-off]

1 hour ago, ChampionAsh5357 said:

For death persisting and changing between dimensions, you should probably read over the forge documentation and look at some implementations (credits to Choonster). As for the data when the player joins, if the data is being reset to zero (assuming your write method is correct), then your error probably comes from incorrectly reading the values back. Another error I can think of has to do with logical sides, but this would have to deal with synchronization issues depending on how you call and read the information given.

I modified my mana class a bit, and now it correctly reads the saved value when the player rejoins the game (checked by printing inside readnbt), so it's being saved/read correctly now. I.e. if it's 124/256 when exiting, it's 124/256 when rejoining. But when I then fall, absorb damage, etc, the server's counter reads back to the maximum. This is definitely a server/client issue right? It's uninitialized on the client so it still prints 0 there, while it's 256 on the server.

 

So correct me if I'm wrong: I handle the mana counter on the server, and when the player falls, the event fires and if on the logical server, I decrement the mana counter. Then when I exit the game, the game writes nbt data to the client, which I must then write back to server upon rejoining the game. Is that about right?

Edited May 23, 2020 by k-off

[k-off]

I think I got it, my problem was that when the player joins the world, I was initializing the member variables as if it was uninitialized, so it kept setting to 256.