1.7.10 Custom Entity Command Based AI

muetakappaepsilon · August 24, 2016

I have been working on a mod that includes an entity (EntityCommoner) that responds to custom user commands. To get started, I tried to get the commoner to go to the player's position at the time the "$come" command is issued. The AI task should change state to active when this happens. Sometimes it works fine and the entity moves to the correct location. However, the task state sometimes alternates every tick between active and inactive and the entity does not move or respond, and I have no clue as to why. In the output below, should ex should either be false or true for a while, not alternating on every tick. The target coordinates alter between what they should be (the player's coordinates when the command is issued) and what they were previously, if that helps anyone.

Below is the relevant code and console output from a print staement in the entity's onUpdate function.

Command Handler

/*

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* To change this template file, choose Tools | Templates

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*/

package com.mike1.command;

import com.mike1.entity.commoners.EntityCommoner;

import cpw.mods.fml.common.eventhandler.SubscribeEvent;

import net.minecraft.entity.Entity;

import net.minecraft.entity.EntityLivingBase;

import net.minecraft.entity.player.EntityPlayer;

import net.minecraft.util.ChatComponentText;

import net.minecraft.world.World;

import net.minecraftforge.common.MinecraftForge;

import net.minecraftforge.event.ServerChatEvent;

/**

*

* @author Mike

*/

public class CommandHandler {

public static void register() {

MinecraftForge.EVENT_BUS.register(new CommandHandler());

}

@SubscribeEvent

public void ServerChat(ServerChatEvent event) {

EntityPlayer player = (EntityPlayer) event.player;

String message = event.message;

if (message.startsWith("$")) {

// then it is a command

processCommand(player, message); // process it

if (event.isCancelable()) { // cancel it

event.setCanceled(true); // so no one else sees it

}

private void processCommand(EntityPlayer player, String message) {

String[] arguments = message.split(" ");

if (arguments.length < 1) { // check to make sure there is a command, there should be

return;

}

String command = arguments[0];

String[] args = new String[arguments.length - 1];

if (arguments.length > 1) { // check to make sure there is a command, there should be

for (int i = 1; i < arguments.length; i++) {

args[i - 1] = arguments;

}

command = command.substring(1); // cut off the '$'

if (false) {// true for printing command

System.out.println("Command: " + command);

for (String a : args) {

System.out.println(a);

}

if (command.equals("hey")) {

sayHey(player);

} else if (command.equals("help")) {

showHelp(player);

} else if (command.equals("commoner")) {

summonCommoner(player, args);

} else if (command.equals("come")) {

nearestCommonerToEntity(player, player);

} else if (command.equals("stop")) {

nearestCommonerStop(player);

} else {

notCommandMessage(command, player);

}

private void sayHey(EntityPlayer player) {

player.addChatComponentMessage(new ChatComponentText(

"Hey " + player.getDisplayName()));

}

private void showHelp(EntityPlayer player) {

String splitter = " ||| ";

String help = "--Commands--" + splitter;

help += "hey - says hey to the user" + splitter;

help += "help - shows this dialogue";

player.addChatComponentMessage(new ChatComponentText(help));

}

private void notCommandMessage(String command, EntityPlayer player) {

player.addChatComponentMessage(new ChatComponentText(

"\"" + command + "\" is not a command."));

}

/// commoner commands

private void summonCommoner(EntityPlayer player, String[] args) {

double x = player.posX;

double y = player.posY;

double z = player.posZ;

World world = player.worldObj;

Entity entity = new EntityCommoner(world);

entity.setPosition(x, y, z);

world.spawnEntityInWorld(entity);

}

private void nearestCommonerToEntity(EntityPlayer player,

EntityLivingBase entity) {

EntityCommoner c = EntityCommoner.getClosest(player);

if (c != null) {

c.goTo(entity);

}

private void nearestCommonerStop(EntityPlayer player) {

EntityCommoner c = EntityCommoner.getClosest(player);

if (c != null) {

c.stop();

}

EntityCommoner

/*

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* To change this template file, choose Tools | Templates

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*/

package com.mike1.entity.commoners;

import com.mike1.entity.ai.EntityAIGoToPosition;

import java.util.ArrayList;

import java.util.List;

import net.minecraft.entity.Entity;

import net.minecraft.entity.EntityLiving;

import net.minecraft.entity.EntityLivingBase;

import net.minecraft.entity.SharedMonsterAttributes;

import net.minecraft.entity.ai.EntityAILookIdle;

import net.minecraft.entity.ai.EntityAISwimming;

import net.minecraft.util.DamageSource;

import net.minecraft.world.World;

/**

*

* @author Mike

*/

public class EntityCommoner extends EntityLiving {

public static List<EntityCommoner> entities = new ArrayList<EntityCommoner>();

public static final double minDetectionDistance = 100;

public static EntityCommoner getClosest(Entity entity) {

return EntityCommoner.getClosest(entity.posX, entity.posY,

entity.posZ);

}

public static EntityCommoner getClosest(double x, double y, double z) {

double minDistance = Double.MAX_VALUE;

EntityCommoner closest = null;

for (EntityCommoner commoner : entities) {

double dist = commoner.getDistance(x, y, z);

if (dist < minDistance) {

minDistance = dist;

closest = commoner;

}

if (minDistance > minDetectionDistance) {

return null;

}

return closest;

}

public static final String unsomethingName = "EntityCommoner";

public static final double moveSpeed = 0.25;

public static final double maxHitpoints = 20;

// un static

private EntityAIGoToPosition goToPosition;

public EntityCommoner(World world) {

super(world);

float minDetectionDistanceF = (float) (EntityCommoner.minDetectionDistance);

this.setSize(0.6F, 1.8F);

this.getNavigator().setBreakDoors(true);

this.getNavigator().setAvoidsWater(false);

EntityCommoner.entities.add(this);

this.clearAITasks();

this.tasks.addTask(0, new EntityAISwimming(this));

this.goToPosition = new EntityAIGoToPosition(this, 1.5,

1.0F,

minDetectionDistanceF);

this.tasks.addTask(1, this.goToPosition);

this.goToPosition.deactivate();

this.tasks.addTask(10, new EntityAILookIdle(this));

}

@Override

protected void applyEntityAttributes() {

super.applyEntityAttributes();

//this.getEntityAttribute(SharedMonsterAttributes.followRange).setBaseValue(80D);

this.getEntityAttribute(SharedMonsterAttributes.movementSpeed).setBaseValue(

EntityCommoner.moveSpeed);

//this.getEntityAttribute(SharedMonsterAttributes.attackDamage).setBaseValue(2.0D);

this.getEntityAttribute(SharedMonsterAttributes.maxHealth).setBaseValue(

EntityCommoner.maxHitpoints);

//this.getEntityAttribute(SharedMonsterAttributes.knockbackResistance).setBaseValue(25.0D);

}

@Override

public void onUpdate() {

System.out.println("should ex: " + this.goToPosition.shouldExecute());

System.out.println(

this.goToPosition.xTarget + " : " + this.goToPosition.zTarget);

//System.out.println(this.goToPosition.isActive());

super.onUpdate();

}

@Override

protected boolean isAIEnabled() {

return true;

}

private void clearAITasks() {

tasks.taskEntries.clear();

targetTasks.taskEntries.clear();

}

public void stop() {

this.goToPosition.deactivate();

}

public boolean isStopped() {

if (this.goToPosition.isActive()) {

return false;

} else {

return true;

}

public void goTo(double x, double y, double z) {

//System.out.println("goto called");

this.goToPosition.activate();

this.goToPosition.xTarget = x;

this.goToPosition.yTarget = y;

this.goToPosition.zTarget = z;

//System.out.println(

// this.goToPosition.xTarget + " : " + this.goToPosition.zTarget);

//System.out.println("from go to: " + x + " : " + z);

//System.out.println(this.goToPosition.isActive());

//System.out.println("going to " + x + " : " + y + " : " + z);

}

public void goTo(EntityLivingBase entity) {

this.goTo(entity.posX, entity.posY, entity.posZ);

}

@Override

public void onDeath(DamageSource ds) {

EntityCommoner.entities.remove(this);

super.onDeath(ds);

}

/**

* Determines if an entity can be despawned, used on idle far away entities

*

* @return

*/

@Override

protected boolean canDespawn() {

return false;

}

/**

*

* @return

*/

@Override

public boolean allowLeashing() {

return false;

}

// sounds --------------------

/**

* Returns the sound this mob makes while it's alive.

*

* @return

*/

@Override

protected String getLivingSound() {

return "mob.villager.idle";

}

/**

* Returns the sound this mob makes when it is hurt.

*

* @return

*/

@Override

protected String getHurtSound() {

return "mob.villager.hit";

}

/**

* Returns the sound this mob makes on death.

*

* @return

*/

@Override

protected String getDeathSound() {

return "mob.villager.death";

}

EntityAIGoToPosition

package com.mike1.entity.ai;

import com.mike1.entity.commoners.EntityCommoner;

import net.minecraft.entity.ai.EntityAIBase;

import net.minecraft.pathfinding.PathNavigate;

import net.minecraft.util.MathHelper;

import net.minecraft.world.World;

public class EntityAIGoToPosition extends EntityAIBase {

private EntityCommoner theCommoner;

World theWorld;

private double moveSpeed;

private PathNavigate commonerPathfinder;

private int field_75343_h;

float maxDist;

float minDist;

private boolean field_75344_i;

private static final String __OBFID = "CL_00001585";

public double xTarget;

public double yTarget;

public double zTarget;

private boolean active;

public EntityAIGoToPosition(EntityCommoner theEntity, double speed,

float minimumDistance, float maximumDistance) {

this.theCommoner = theEntity;

this.theWorld = theEntity.worldObj;

this.moveSpeed = speed;

this.commonerPathfinder = theEntity.getNavigator();

this.minDist = minimumDistance;

this.maxDist = maximumDistance; // does nothing right now

this.deactivate();

this.setMutexBits(3);

}

/**

* Returns whether the EntityAIBase should begin execution.

*

* @return

*/

@Override

public boolean shouldExecute() {

//System.out.println("from should ex: " + this.isActive());

//System.out.println(

// "from should ex: " + this.xTarget + " : " + this.zTarget);

if (!this.isActive()) {

return false;

} else if (this.theCommoner.getDistanceSq(this.xTarget,

this.yTarget,

this.zTarget) < ((double) (this.minDist * this.minDist))) {

this.deactivate();

return false;

} else if (!this.commonerPathfinder.noPath()) {

this.deactivate();

return false;

} else {

return true;

}

/**

* Returns whether an in-progress EntityAIBase should continue executing

*

* @return

*/

@Override

public boolean continueExecuting() {

if (this.shouldExecute()) {

return true;

} else {

return false;

}

/**

* Execute a one shot task or start executing a continuous task

*/

@Override

public void startExecuting() {

this.field_75343_h = 0;

this.field_75344_i = this.theCommoner.getNavigator().getAvoidsWater();

}

/**

* Resets the task

*/

@Override

public void resetTask() {

this.deactivate();

this.commonerPathfinder.clearPathEntity();

}

/**

* Updates the task

*/

@Override

public void updateTask() {

this.theCommoner.getLookHelper().setLookPosition(

this.xTarget,

this.yTarget,

this.zTarget,

10.0F,

(float) this.theCommoner.getVerticalFaceSpeed());

if (this.isActive()) {

if (--this.field_75343_h <= 0) {

this.field_75343_h = 10;

if (!this.commonerPathfinder.tryMoveToXYZ(

this.xTarget,

this.yTarget,

this.zTarget,

this.moveSpeed)) {

if (!this.theCommoner.getLeashed()) {

if (this.theCommoner.getDistanceSq(

this.xTarget,

this.yTarget,

this.zTarget) >= 144.0D) {

int i = MathHelper.floor_double(

this.xTarget) - 2;

int j = MathHelper.floor_double(

this.zTarget) - 2;

int k = MathHelper.floor_double(

this.yTarget);

for (int l = 0; l <= 4; ++l) {

for (int i1 = 0; i1 <= 4; ++i1) {

if ((l < 1 || i1 < 1 || l > 3 || i1 > 3) && World.doesBlockHaveSolidTopSurface(

this.theWorld, i + l, k - 1, j + i1) && !this.theWorld.getBlock(

i + l, k, j + i1).isNormalCube() && !this.theWorld.getBlock(

i + l, k + 1, j + i1).isNormalCube()) {

this.theCommoner.setLocationAndAngles(

(double) ((float) (i + l) + 0.5F),

(double) k,

(double) ((float) (j + i1) + 0.5F),

this.theCommoner.rotationYaw,

this.theCommoner.rotationPitch);

this.commonerPathfinder.clearPathEntity();

return;

}

public void activate() {

//System.out.println("activate task");

this.active = true;

}

public void deactivate() {

//System.out.println("Deactive task");

this.active = false;

}

public boolean isActive() {

if (this.active) {

return true;

} else {

return false;

}

some console output

[19:28:56] [server thread/INFO]: Starting integrated minecraft server version 1.7.10

[19:28:56] [server thread/INFO]: Generating keypair

[19:28:56] [server thread/INFO] [FML]: Injecting existing block and item data into this server instance

[19:28:56] [server thread/INFO] [FML]: Applying holder lookups

[19:28:56] [server thread/INFO] [FML]: Holder lookups applied

[19:28:56] [server thread/INFO] [FML]: Loading dimension 0 (New World) (net.minecraft.server.integrated.IntegratedServer@390d6d6b)

[19:28:56] [server thread/INFO] [FML]: Loading dimension 1 (New World) (net.minecraft.server.integrated.IntegratedServer@390d6d6b)

[19:28:56] [server thread/INFO] [FML]: Loading dimension -1 (New World) (net.minecraft.server.integrated.IntegratedServer@390d6d6b)

[19:28:56] [server thread/INFO]: Preparing start region for level 0

[19:28:58] [server thread/INFO] [sTDOUT]: [com.mike1.entity.commoners.EntityCommoner:onUpdate:95]: should ex: false

[19:28:58] [server thread/INFO] [sTDOUT]: [com.mike1.entity.commoners.EntityCommoner:onUpdate:96]: 0.0 : 0.0

[19:28:58] [server thread/INFO]: Changing view distance to 12, from 10