Explosive Arrows

I would like some code that will make it so when a player shoots an arrow, it will make a TNT sized explosion where the arrow lands. Thanks!

 

You probably only need the last one, but I included all of them for completions sake.

 

MrFigg is there one that shows how to code an explosive arrow plugin?

 

... The last one... Like I said...

Edit: Also, you seem fairly new to this so I'm pretty sure you'll ask about this eventually. These videos are kinda old and still use the old event system, so you'll have to convert them to the new event system. (http://wiki.bukkit.org/Introduction_to_the_New_Event_System) But the code inside the listener should work fine.

 

MrFigg can I have link to that video because I can't see the link or title. Thanks!

 

Huh, when you post a link to youtube the forum auto-converts it. Interesting. Anyway here's the link to the video on his website; http://betterphp.co.uk/video.html?vid=_-WytSFkNK0

 

MrFigg thx sorry for bothering, I didn't see it probably because I was in my iPad.

 

Code:

 @EventHandler(priority=EventPriority.HIGH)
    public void onProjectileHit(ProjectileHitEvent event) {
      Entity entity = event.getEntity();
      if ((entity instanceof Arrow)) {
        Arrow arrow = (Arrow)entity;
        Entity shooter = arrow.getShooter();
        if ((shooter instanceof Player)) {
          Player player = (Player)shooter;
            player.getWorld().createExplosion(arrow.getLocation(), 5.0F);
        }
      }
    }

Be advised this will destroy blocks regardless of any protections in place.

 

Sephi is there a way to not damage blocks, but still give players damage?

 

0.0f instead of 5.0f

 

I've been looking into that myself but I can't for the life of me how to figure out how to replicate exactly a TNT explosion where damage is factored in by the proximity of your location to the initial blast, while leaving the surrounding blocks intact.

As Tirelessly said, you can negate the explosion power from 5.0F to 0.0F, but that will also negate all damage the surrounding entities receive.

 

what you do is get all the blocks within the radius of the explosion on the hit event, get the world of the hit event, make the explosion, restore the blocks that have been removed, clear the list/hashmap/hashset/whatever you are using to store blocks.

Sephi
there is the possibility of a player going through a portal, at the exact time before this line gets fired, making it so you will actually destroy blocks in the nether/end. To combat this, just do arrow.getWorld(), or event.getWorld()
player.getWorld().createExplosion(arrow.getLocation(), 5.0F);

 

Or

Code:

float size = 4.0F;
net.minecraft.server.Entity arrow = (net.minecraft.server.Entity)((CraftEntity)entity).getHandle();
Explosion explosion = new Explosion(arrow.world, arrow, arrow.locX, arrow.locY, arrow.locZ, size);
 
explosion.a();

where entity is the arrow

 

Thats the same exact thing, except it uses NMS code, which is subject to break. I would recommend using my way, because it uses bukkit methods, and Location contains world, x, y, z, pitch, and yaw, so you don't have to get all the info yourself.

 

My way doesn't even damage the blocks, where in your way you have to go back and replace each block, which could potentially leave some things non repaired (chests, signs, etc.). It could break, yes, so it's just preference I guess.

EDIT: Also with a large enough explosion, replacing each block from a hashmap could get quite laggy.

 

Hmm decisions, decisions. I could see Jnorr's method problematic if it blew up a player's worldguarded / faction protected chests full of goodies.. then it simply restores an empty chest, or worse, a chest with the original items and the explosion causing the chest to burst with the items on the ground (thus duplicating the contents of the chest). I know it is possible to store and restore the data inside the chest as well, but it is a bit beyond my league.. still pretty new to this.

Signs, I wouldn't be so concerned about unless it permanently deleted the text.. which it possibly could if all I did was store the block material and restore it after the event... that or I'm just being paranoid.

Kyle's way I can kind of understand on its own, but my dumbness (or maybe being awake for 30 hours is just making me brain dead at the moment sigh) is preventing me from seeing how it would be used in the listener's Event Handler..

I'll be doing even more research to try and understand both of these ways. Sleep might be a healthy option too! haha

 

kyle1320 You can use BlockStates, which are very fast, because your just getting info on the blocks. Problem solved

 

OR, you could do EntityExplodeEvent.blockList().remove(yourBlock). Because you are not storing the value of blockList in a local variable, blockList just passes a reference of the ArrayList<Block> in EntityExplodeEvent. You can clear it completely by .blockList().clear(), if you want to completely disable it. Its a nicer way of the reflection equivalent:

Code:Java

 
Field blockList = EntityExplodeEvent.class.getDeclaredField("blockList");
......
......
<in your event handler, where e is the EntityExplodeEvent>
blockList.set(e, ((List)blockList.get(e)).remove(yourBlock));
 

I do not advise using the above code. Just use the reference.

Jnorr44 Using this method, the chest wouldn't even be removed, so you wouldn't have to deal with storing the contents of the chest and readding them. More efficient, too.

 

Umm... yea. Making an explosion that deals full entity damage without doing block damage is a lot easier than ether Jnorr44 or kyle1320s suggestions. Just use the EntityExplodeEvent Icyeye mentioned. Though you don't even need to get that complicated. Just do something like this;

Code:JAVA

public class ExplodingArrow extends JavaPlugin implements Listener {
    private boolean clearBlocks = false;
 
    public void onEnable() {
        getServer().getPluginManager().registerEvents(this, this);
    }
 
    @EventHandler(priority=EventPriority.HIGHEST)
    public void onProjectileHit(ProjectileHitEvent event) {
        Entity entity = event.getEntity();
        if((entity instanceof Arrow)) {
            Arrow arrow = (Arrow) entity;
            Entity shooter = arrow.getShooter();
            if((shooter instanceof Player)) {
                noBlockExplosion(arrow.getLocation(), 5.0F);
                arrow.remove();
            }
        }
    }
 
    public void noBlockExplosion(Location location, float force) {
        clearBlocks = true;
        location.getWorld().createExplosion(location, force);
        clearBlocks = false;
    }
 
    @EventHandler(priority=EventPriority.HIGHEST)
    public void onEntityExplode(EntityExplodeEvent event) {
        if(clearBlocks) event.blockList().clear();
    }
}

I know it's kinda ugly having a boolean used like that but it's quite effective. I'd just put it, the explosion listener, and the noBlockExlposion method in it's own class to keep it out of sight.

 

MrFigg This idea works perfectly fine.

Icyene This idea also works great, though seems more efficient, and as MrFigg admitted, using the boolean as he did wouldn't exactly be encourage despite it having full functionality.

I think I will use Icyene's method, thank you so much to everyone who helped. I hope this helps the topic creator here, as I will mark my thread (that was created before this one, but basically asking the same thing) as [Solved].

http://forums.bukkit.org/threads/solved-onprojectilehit.101715/

 

Sephi yes?

 

chasechocolate If you don't like messing around with the complexity of Lists (though once you understand them they really aren't that complex), I recommend using MrFigg's code as at the very least it functions just as effectively as he states it does, both ways were tested.

 

Sephi NMS is much more complicated than lists. And will have to be updated when a() is renamed.

MrFigg Thas not very safe... You should store the id of the arrow and boolean in a Hashmap or Tuple. And have a list of those.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Not true.
It calls this code:
https://github.com/Bukkit/CraftBukk...a/org/bukkit/craftbukkit/CraftWorld.java#L440
Which calls this code:
https://github.com/Bukkit/CraftBukk...in/java/net/minecraft/server/World.java#L1519
Now look for yourself was explosion.a() and explosion.a(true); does: It fires all needed events for protection plugins.
https://github.com/Bukkit/CraftBukkit/blob/master/src/main/java/net/minecraft/server/Explosion.java


For a prove I compiled this:

Code:java

public class ExplosiveArrows extends JavaPlugin implements Listener
{
  public void onEnable()
  {
    getServer().getPluginManager().registerEvents(this, this);
  }
 
  @EventHandler(priority=EventPriority.HIGH)
  public void onProjectileHit(ProjectileHitEvent event)
  {
    Entity entity = event.getEntity();
    if(entity instanceof Arrow && ((Arrow)entity).getShooter() instanceof Player)
      entity.getWorld().createExplosion(entity.getLocation(), 5.0F);
  }
}

(which is basically the same, just simplified) and used it together with BananaRegion:

(needs some time to upload/convert).

 

Very true, I would never actually use that as is. Just a proof of concept.

 

As long as minecraft is single-threaded this is perfectly safe as it's impossible that another ExplosionEvent gets fired while the boolean is true.