Solved Throwing back an entity

Hi there!


For my current project i need to throw back entities when they're rightclicked. They shall fly way behind, in the direction the damager looks at.

For testing, i wrote the following code:

Code:java

 
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.entity.EntityDamageByEntityEvent;
import org.bukkit.plugin.java.JavaPlugin;
import org.bukkit.util.Vector;
 
public class Main extends JavaPlugin implements Listener {
 
public void onEnable() {
getServer().getPluginManager().registerEvents(this, this);
}
 
@EventHandler
public void onDamageEntity(EntityDamageByEntityEvent e) {
if (e.getDamager() instanceof Player) {
Vector direction = e.getDamager().getLocation().getDirection();
e.getEntity().setVelocity(new Vector(direction.getX() * 20, direction.getY() * 5, direction.getZ() * 20));
}
}
 
}

When i now right click an entity, it is thrown back, but it does not gain any height, regardless if i multiply direction.getY() by 5 or by 50. Does not make any sense to me, i hope you can tell me why it is like this.


~Robin Bi

 

Code:java

Entity.setVelocity(Player.getLocation().getDirection().multiply(2D));

 

Joiner Sorry, but this seems to not multiply the Y as well. The entities don't raise.

 

Robin Bi It depends on where the player is in relation to the entity.

 

Joiner Yeah, didn't get this, sorry. But then i have to change the line of code anyways because the entitie should fly high in the air, also if the damager does look at the ground...

 

Robin Bi

Code:java

Vector direction = Player.getLocation().getDirection().multiply(2D);
Entity.setVelocity(direction.setY(1));

 

Joiner Now it's kinda embarrassing but i see no difference between

Code:java

Vector direction = e.getDamager().getLocation().getDirection().multiply(2D);
            e.getEntity().setVelocity(direction.setY(1));

and

Code:java

Vector direction = e.getDamager().getLocation().getDirection().multiply(10D);
            e.getEntity().setVelocity(direction.setY(50));

 

Why?

 

Joiner Because you're giving me one solution after the other and I just don't get it ^^

 

Robin Bi I may be wrong.

 

Joiner Well you seem to have experience with velocities! Don't you have any idea left?

 

No.

Code:java

Entity.setVelocity(Entity.getVelocity().setY(5));

 

Joiner Does not work either, but thanks for your time.

 

Robin Bi Check your code, might be buggy.
Else, someone more experienced will help you.
But, you can read https://forums.bukkit.org/threads/tutorial-how-to-calculate-vectors.138849/.

 

#Bump?

 

Robin Bi This works. If not, make a video.

Code:java

Entity.setVelocity(Player.getLocation().getDirection().multiply(3));

 

Joiner Yes it works, but as i mentioned before in this thread, it does not throw the entity as high in the air as i want. And multiplying the Y for its own did not work either, as we bothes detected.

 

Robin Bi

 

Robin Bi get the player's direction Vector, multiply by a number (depending on how far you want it to fly), and manually set the y to a value (> 1 should make them fly noticeably high)

 

For everyone who has the same problem:

Code:java

@EventHandler
public void onEntityDamage(EntityDamageByEntityEvent event) {
    event.setCancelled(true);
    Vector direction = event.getDamager().getLocation().getDirection();
    event.getEntity().setVelocity(new Vector(direction.getX() * 2.5D, 1.5D, direction.getZ() * 2.5D));
}

works. The problem was that the Minecraft-integrated knockback when damaging an entity was "more important" than my own Velocity. When cancelling the event first, the Entity is not damaged (what can be done via another line of code though) but thrown away.

However, thanks to everyone who helped me.
fireblast709 , Joiner



~Robin Bi