Events

[Dronus86]

I'm a little shaky on the events. I understand the concept well enough, but I don't know a lot of the specifics or standards. Is it possible to listen for 'any' in-game event, and then parse the events to only use what you need?

I'm aware this isn't standard, but if it is possible, is it a Really Bad Idea? If so, why? Is there significant overhead when doing this?

 

Thanks!

[jabelar]

You can learn more at my tutorial: http://jabelarminecraft.blogspot.com/p/minecraft-forge-172-event-handling.html

 

Anyway, events are meant to be used -- they are purposeful hooks to allow modders to intercept common points where different behavior may be useful.

 

If you have custom classes, then instead of events it is usually more logical to use their methods (@Override things like onUpdate).  Events are more applicable to modifying behavior of vanilla classes.

 

Some examples:

  - if you wanted something to happen when a vanilla block is broken by a vanilla item, use an event (probably BlockBreak)

  - if you wanted something to happen when a custom block is broken by a vanilla item, use method in custom block.

  - if you wanted something to happen when a vanilla block is broken by a custom item, use method in custom item.

  - if you wanted something to happen when a custom block is broken by a custom item, use method in either custom block or item.

 

So basically first consider if the code can run in your custom classes.  If not, events are quite acceptable.

 

In terms of the specific event to use, it is better to use the one that is most specific.  For example, if you want to modify the player drops you could use either LivingDropsEvent or PlayerDropsEvent, but in the former you'd have to check if the entity was the player each time which is a bit wasteful.

 

The events that can cause real perf problems are the tick events.  For the most part, Minecraft runs a LOT of code every tick, so a bit of code isn't too big of a deal.  But if you're doing complicated things like testing every block in the world every tick, you will cause trouble.  In those cases you need to use techniques for perf optimization (basically just make sure nothing is executing unnecessarily).  But tick events are really useful if you want to do processing across a lot of different classes.  For example, if you wanted to do something special if three players all were within some special area it makes more logical sense to check for that in a tick event than to have each player class trying to check it.

 

Overall, events are great.  I get "addicted" to them sometimes as they are logically an easy way to think about certain code, but you should check for other methods that may already be available to your need before going to events.

[Dronus86]

Thanks! I'll browse your tutorials before I ask more questions, but it seems like you may have confirmed that I should be using events. Unfortunately, I don't actually fall into any of those categories - It's going to be based off of NBT in the ItemStack rather than whether or not the subject/object is vanilla or from a mod. And the goal is to be able to add this NBT to a variety of things, including vanilla objects and (hopefully) other mods objects.

 

If any of that sounds crazy impossible, I'd be happy to hear why before I delve much deeper into this abyss.

[Ghostrec35]

What exactly do you want to do with this NBT data?