EntityAIMate.java

package net.minecraft.entity.ai;

import java.util.Iterator;
import java.util.List;
import java.util.Random;
import net.minecraft.entity.EntityAgeable;
import net.minecraft.entity.item.EntityXPOrb;
import net.minecraft.entity.passive.EntityAnimal;
import net.minecraft.world.World;

public class EntityAIMate extends EntityAIBase
{
    private EntityAnimal theAnimal;
    World theWorld;
    private EntityAnimal targetMate;

    /**
     * Delay preventing a baby from spawning immediately when two mate-able animals find each other.
     */
    int spawnBabyDelay = 0;

    /** The speed the creature moves at during mating behavior. */
    float moveSpeed;

    public EntityAIMate(EntityAnimal par1EntityAnimal, float par2)
    {
        this.theAnimal = par1EntityAnimal;
        this.theWorld = par1EntityAnimal.worldObj;
        this.moveSpeed = par2;
        this.setMutexBits(3);
    }

    /**
     * Returns whether the EntityAIBase should begin execution.
     */
    public boolean shouldExecute()
    {
        if (!this.theAnimal.isInLove())
        {
            return false;
        }
        else
        {
            this.targetMate = this.getNearbyMate();
            return this.targetMate != null;
        }
    }

    /**
     * Returns whether an in-progress EntityAIBase should continue executing
     */
    public boolean continueExecuting()
    {
        return this.targetMate.isEntityAlive() && this.targetMate.isInLove() && this.spawnBabyDelay < 60;
    }

    /**
     * Resets the task
     */
    public void resetTask()
    {
        this.targetMate = null;
        this.spawnBabyDelay = 0;
    }

    /**
     * Updates the task
     */
    public void updateTask()
    {
        this.theAnimal.getLookHelper().setLookPositionWithEntity(this.targetMate, 10.0F, (float)this.theAnimal.getVerticalFaceSpeed());
        this.theAnimal.getNavigator().tryMoveToEntityLiving(this.targetMate, this.moveSpeed);
        ++this.spawnBabyDelay;

        if (this.spawnBabyDelay >= 60 && this.theAnimal.getDistanceSqToEntity(this.targetMate) < 9.0D)
        {
            this.spawnBaby();
        }
    }

    /**
     * Loops through nearby animals and finds another animal of the same type that can be mated with. Returns the first
     * valid mate found.
     */
    private EntityAnimal getNearbyMate()
    {
        float f = 8.0F;
        List list = this.theWorld.getEntitiesWithinAABB(this.theAnimal.getClass(), this.theAnimal.boundingBox.expand((double)f, (double)f, (double)f));
        double d0 = Double.MAX_VALUE;
        EntityAnimal entityanimal = null;
        Iterator iterator = list.iterator();

        while (iterator.hasNext())
        {
            EntityAnimal entityanimal1 = (EntityAnimal)iterator.next();

            if (this.theAnimal.canMateWith(entityanimal1) && this.theAnimal.getDistanceSqToEntity(entityanimal1) < d0)
            {
                entityanimal = entityanimal1;
                d0 = this.theAnimal.getDistanceSqToEntity(entityanimal1);
            }
        }

        return entityanimal;
    }

    /**
     * Spawns a baby animal of the same type.
     */
    private void spawnBaby()
    {
        EntityAgeable entityageable = this.theAnimal.createChild(this.targetMate);

        if (entityageable != null)
        {
            this.theAnimal.setGrowingAge(6000);
            this.targetMate.setGrowingAge(6000);
            this.theAnimal.resetInLove();
            this.targetMate.resetInLove();
            entityageable.setGrowingAge(-24000);
            entityageable.setLocationAndAngles(this.theAnimal.posX, this.theAnimal.posY, this.theAnimal.posZ, 0.0F, 0.0F);
            this.theWorld.spawnEntityInWorld(entityageable);
            Random random = this.theAnimal.getRNG();

            for (int i = 0; i < 7; ++i)
            {
                double d0 = random.nextGaussian() * 0.02D;
                double d1 = random.nextGaussian() * 0.02D;
                double d2 = random.nextGaussian() * 0.02D;
                this.theWorld.spawnParticle("heart", this.theAnimal.posX + (double)(random.nextFloat() * this.theAnimal.width * 2.0F) - (double)this.theAnimal.width, this.theAnimal.posY + 0.5D + (double)(random.nextFloat() * this.theAnimal.height), this.theAnimal.posZ + (double)(random.nextFloat() * this.theAnimal.width * 2.0F) - (double)this.theAnimal.width, d0, d1, d2);
            }

            this.theWorld.spawnEntityInWorld(new EntityXPOrb(this.theWorld, this.theAnimal.posX, this.theAnimal.posY, this.theAnimal.posZ, random.nextInt(7) + 1));
        }
    }
}