Teleporting a Player Every Second.

[gmod622]

Hey all!

 

So I recently created an item that on eaten, will give potion effects and teleport the player around, however:

- The random function only teleports them in a positive x & z ( Want to keep y positive )

- The 'For-Loop' runs too quickly

 

So how would I slow this function down.

 

here is the current state of the fuction:

 

@Override
protected void onFoodEaten(ItemStack stack, World worldIn, EntityPlayer player) {
	super.onFoodEaten(stack, worldIn, player);
	player.addPotionEffect(new PotionEffect(MobEffects.NAUSEA, 100, 3));
	player.addPotionEffect(new PotionEffect(MobEffects.BLINDNESS, 100, 3));

	int playerX = player.getPosition().getX();
	int playerY = player.getPosition().getY();
	int playerZ = player.getPosition().getZ();
	int max = 5;
	int min = 0;

	for(int i = 1; i < 5; i++) {
	player.setPosition(playerX + min + (int)(Math.random() * ((max - min) + 1)) , playerY + min + (int)(Math.random() * ((max - min) + 1)), playerZ + min + (int)(Math.random() * ((max - min) + 1)));
	}
}

 

and yes, I have tried:

 

	player.setPosition(playerX + rand.nextInt(5), playerY + rand.nextInt(5), playerZ + rand.nextInt(5));

 

However, it wants me to make the

Random rand;

to

Random rand = null;

 

Also, I dont think nextint uses negitive numbers.

[hugo_the_dwarf]

you will have to give the player some sort of state (capability, or a combo of effects) that you can reference, then every player tick (or intervals of ticks) while the player is in the state apply your teleporting. And yes Random().nextInt() only takes postitives, however you can make the negative with another random

 

playerX + New Random().nextInt(5) * (New Random.nextInt(2) == 0 ? 1 : -1)

 

more or less the above will get a random of 0-4 then multiply by 1 or -1 if the random returns 0 or 1 making that 0-4 value negative or leaving it positive

 

also it should be

 

Random rand = new Random();

 

then call rand.nextInt();

 

EDIT:

 

Also don't use my example of new Random().nextInt(); it's better to declare an instance like above "Random rand = new Random();" and call it, or get the RNG from the player most entities have a function called "getRNG()" which returns a Random so you can use player.getRNG().nextInt();

[Draco18s]

Or...New Random().nextInt(10) - 5

(not that "New Random().nextInt(...)" will actually compile)

[gmod622]

So how do ticks work in code? If i uses a int that increases and at 20 (one second in the game) will fire a function.. however, I dont know if code is updated in sink with ingame ticks

 

ALSO:

Some times it wont teleport me due to:

 

[21:58:44] [server thread/WARN]: Player742 moved wrongly!

[hugo_the_dwarf]

You could subscribe to a tick event, preferably a playertick event. and in there check for if(player had special potion effect && player.world.time % 20 == 0) do teleport logic;

 

The game is in a constant loop, and each loop is more or less a tick, 20 MC ticks are roughly 1 second RL time. A tick event as it seems is run every tick. So instead of a for loop that will run x amount of times teleporting in a single game loop, you space it out every 20 ticks

[gmod622]

Which event would you recommend or how would I find a event/create one that functions like I want it...

New to events.

 

However, i have the code for when the event is called.

[Animefan8888]

Which event would you recommend or how would I find a event/create one that functions like I want it...

New to events.

 

However, i have the code for when the event is called.

Hugo suggested PlayerTickEvent and there is plenty of documentation on the internet I specifically like cool alias'.

http://www.minecraftforum.net/forums/mapping-and-modding/mapping-and-modding-tutorials/1571567-forge-1-6-4-1-8-eventhandler-and

Jaeblar has good tutorials.

[hugo_the_dwarf]

not that I'm against Dracos Approach of

rand.nextInt(10) - 5; as it looks like a very elegant solution done with less code and cpu

 

But nextInt() goes from 0 (inclusive) and to the bound (exclusive basically bound - 1)

 

so really the outcomes are (if the bound is 10):

 

-5 0

-4 1

-3 2

-2 3

-1 4

0 5

1 6

2 7

3 8

4 9

 

And just a question regarding my method (as it appears as a horrible approach) how does it "Generate 0 more often" 0 * anything is going to be 0. But if the random gave you a 0, you got a 0. if you got a 1, it might be +pos or -neg same with any other number given.

 

I wouldn't think it would return more 0's unless it's the fact that the bound is so low (0 to 4) that 0 is a higher possibility, but if the goal was to only move randomly 4 blocks left/right and 4 blocks forward/back my method would keep it as 4. where subtracting the number would allow the negative to have a -1 head start?

[Draco18s]

rand(9) - 4, then.

Seriously, it's not that hard to make a linear distribution across any range.

[gmod622]

I have one problem though, it doesn't seem like my event is working.

 

Here is the event:

public class PlayerTickHandler {

	private Minecraft mc;

	// create a constructor that takes a Minecraft argument; now we have it whenever we need it
public PlayerTickHandler(Minecraft mc) {
	this.mc = mc;
}

	@SubscribeEvent
	public void onPlayerTick(PlayerTickEvent event) {
			if (event.phase == Phase.START) {
			if(mc.thePlayer.isPotionActive(ModEvent.eventEffectTeleportation) && mc.thePlayer.getEntityWorld().getWorldTime() % 20 == 0) {
				int playerX = mc.thePlayer.getPosition().getX();
				int playerY = mc.thePlayer.getPosition().getY();
				int playerZ = mc.thePlayer.getPosition().getZ();
				Random rand = new Random();
				mc.thePlayer.setPosition(playerX + rand.nextInt(10) - 5, playerY, playerZ + rand.nextInt(10) - 5);
			}
		}
	}
}

 

and here is the potion registry & the event registry:

 

public class ModEvent {

public static Potion eventEffectTeleportation;


public static void init() {
	eventEffectTeleportation = new PotionEffectTeleportation();
	GameRegistry.register(eventEffectTeleportation);
}
}

 

public class ServerProxy implements CommonProxy {


@Override
public void preInit() {

	// Tile Registry:
	GameRegistry.registerTileEntity(TileEntityCrate.class, "plentifulmisc_crate");

	// GUI Registry:
	NetworkRegistry.INSTANCE.registerGuiHandler(PlentifulMisc.instance, GuiRegistyHandler.getInstance());
	GuiRegistyHandler.getInstance().registerGuiHandler(new GuiHandler(), GuiHandler.getGuiID());
}

@Override
public void init() {
	FMLCommonHandler.instance().bus().register(new PlayerTickHandler(Minecraft.getMinecraft()));
}



}

[Animefan8888]

Your code in the ServerProxy never runs because you never call it, and that is good because you are calling client code in server elements.

FMLCommonHandler.instance().bus().register(new PlayerTickHandler(Minecraft.getMinecraft()));

You should be registering your EventHandler in common code, aka your main mod class.

Why do you have a Minecraft instance when you are given a EntityPlayer instance from the event.

[gmod622]

Okay thanks, however im getting this error now:

 

Caused by: java.lang.NullPointerException
at com.lambda.PlentifulMisc.events.PlayerTickHandler.onPlayerTick(PlayerTickHandler.java:24) ~[PlayerTickHandler.class:?]
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_6_PlayerTickHandler_onPlayerTick_PlayerTickEvent.invoke(.dynamic) ~[?:?]
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90) ~[ASMEventHandler.class:?]
at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:185) ~[EventBus.class:?]
at net.minecraftforge.fml.common.FMLCommonHandler.onPlayerPreTick(FMLCommonHandler.java:360) ~[FMLCommonHandler.class:?]
at net.minecraft.entity.player.EntityPlayer.onUpdate(EntityPlayer.java:215) ~[EntityPlayer.class:?]
at net.minecraft.entity.player.EntityPlayerMP.onUpdateEntity(EntityPlayerMP.java:341) ~[EntityPlayerMP.class:?]
at net.minecraft.network.NetHandlerPlayServer.update(NetHandlerPlayServer.java:174) ~[NetHandlerPlayServer.class:?]
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher$1.update(NetworkDispatcher.java:216) ~[NetworkDispatcher$1.class:?]
at net.minecraft.network.NetworkManager.processReceivedPackets(NetworkManager.java:308) ~[NetworkManager.class:?]
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:195) ~[NetworkSystem.class:?]
... 5 more

[Animefan8888]

Okay thanks, however im getting this error now:

 

Caused by: java.lang.NullPointerException
at com.lambda.PlentifulMisc.events.PlayerTickHandler.onPlayerTick(PlayerTickHandler.java:24) ~[PlayerTickHandler.class:?]
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_6_PlayerTickHandler_onPlayerTick_PlayerTickEvent.invoke(.dynamic) ~[?:?]
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90) ~[ASMEventHandler.class:?]
at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:185) ~[EventBus.class:?]
at net.minecraftforge.fml.common.FMLCommonHandler.onPlayerPreTick(FMLCommonHandler.java:360) ~[FMLCommonHandler.class:?]
at net.minecraft.entity.player.EntityPlayer.onUpdate(EntityPlayer.java:215) ~[EntityPlayer.class:?]
at net.minecraft.entity.player.EntityPlayerMP.onUpdateEntity(EntityPlayerMP.java:341) ~[EntityPlayerMP.class:?]
at net.minecraft.network.NetHandlerPlayServer.update(NetHandlerPlayServer.java:174) ~[NetHandlerPlayServer.class:?]
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher$1.update(NetworkDispatcher.java:216) ~[NetworkDispatcher$1.class:?]
at net.minecraft.network.NetworkManager.processReceivedPackets(NetworkManager.java:308) ~[NetworkManager.class:?]
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:195) ~[NetworkSystem.class:?]
... 5 more

Caused by: java.lang.NullPointerException

at com.lambda.PlentifulMisc.events.PlayerTickHandler.onPlayerTick(PlayerTickHandler.java:24)

This is your problem, something is null on line 24.

[hugo_the_dwarf]

And just a question regarding my method (as it appears as a horrible approach) how does it "Generate 0 more often" 0 * anything is going to be 0. But if the random gave you a 0, you got a 0. if you got a 1, it might be +pos or -neg same with any other number given.

You have two randoms:

 

nextInt(3)nextInt(1) == 0 ? 1 : -1result

010

0-10

111

1-1-1

212

2-1-2

 

As you can see the 0 appears twice in the result column as opposed to every other number, hence it has a higher chance of appearing.

 

actually since I'm using rand.nextInt(2) == 0 ? 1 : -1;

which is a ternary so the random will return 0 or 1. If it is == 0 return 1, else -1

 

so even if I had rand.nextInt(50) == 0 ? 1 : -1;

it would most likely be -1 more often as it could be != 0 as it has more options to pick from (0 to 49)

 

But after I got up and left I figured Dracos is the best choice as my given example that I posted it'd be easier to just add 1, and it'd even it all out

 

rand.nextInt(11) - 5; would give a range of -5 to +5 (including 0) or simply "rand.nextInt((range * 2) + 1) - range;"

[Draco18s]

actually since I'm using rand.nextInt(2) == 0 ? 1 : -1;

which is a ternary so the random will return 0 or 1. If it is == 0 return 1, else -1

 

The fact that it's ternary doesn't matter.  0 * (rand.nextInt(2) == 0 ? 1 : -1) is still 0.

[gmod622]

Ah!

 

So I know whats wrong, however trying to do a nullcheck/falsecheck seems to not work.

 

here is the line thats crashing

			if(mc.thePlayer.isPotionActive(ModEvents.eventEffectTeleportation) && mc.thePlayer.getEntityWorld().getWorldTime() % 20 == 0) {

 

And i just did an else statement and returned, however i get same error

 

 

 

[Animefan8888]

Ah!

 

So I know whats wrong, however trying to do a nullcheck/falsecheck seems to not work.

 

here is the line thats crashing

			if(mc.thePlayer.isPotionActive(ModEvents.eventEffectTeleportation) && mc.thePlayer.getEntityWorld().getWorldTime() % 20 == 0) {

 

And i just did an else statement and returned, however i get same error

Does this ever get called?

public static void init() {
	eventEffectTeleportation = new PotionEffectTeleportation();
	GameRegistry.register(eventEffectTeleportation);
}

Plus

...and that is good because you are calling client code in server elements.

FMLCommonHandler.instance().bus().register(new PlayerTickHandler(Minecraft.getMinecraft()));

You should be registering your EventHandler in common code, aka your main mod class.

Why do you have a Minecraft instance when you are given a EntityPlayer instance from the event.

[gmod622]

I dont think I've given an entityplayer,

 

and does:

FMLCommonHandler.instance().bus().register(new PlayerTickHandler(Minecraft.getMinecraft()));

 

need to be in init() or preInit()

[Animefan8888]

I dont think I've given an entityplayer,

What?

 

and does:

FMLCommonHandler.instance().bus().register(new PlayerTickHandler(Minecraft.getMinecraft()));

 

need to be in init() or preInit()

What Minecraft version are you using?

[gmod622]

1.10

 

Does it matter if i use minecraft instance? or is it just more efficient the other way..

 

[Animefan8888]

1.10

 

Does it matter if i use minecraft instance? or is it just more efficient the other way..

Events are registered with MinecraftForge.EVENT_BUS.register() now no matter which one, and yes it does matter if you use Minecraft instance because that is a client side class.