minecraft-kajetans-mod/src/main/java/me/km/pathfinder/PathfinderGoalDestroyBlock.java

package me.km.pathfinder;

import java.util.Random;
import net.minecraft.entity.EntityLiving;
import net.minecraft.entity.ai.EntityAIBase;
import net.minecraft.util.math.MathHelper;
import net.minecraft.world.World;
import net.minecraft.util.math.BlockPos;
import net.minecraft.util.math.RayTraceResult;
import net.minecraft.util.math.Vec3d;

public class PathfinderGoalDestroyBlock extends EntityAIBase
{
    private final EntityLiving entity;

    public PathfinderGoalDestroyBlock(EntityLiving liv)
    {
        this.entity = liv;
    }

    @Override
    public boolean shouldExecute() 
    {
        if(!entity.world.getGameRules().getBoolean("mobGriefing"))
        {
            return false;
        }
        return entity.getRNG().nextInt(3) == 0;
    }

    @Override
    public void updateTask()
    {
        Random random = entity.getRNG();
        World world = entity.world;
        int x = MathHelper.floor(entity.posX - 2.0D + random.nextDouble() * 4.0D);
        int y = MathHelper.floor(entity.posY + random.nextDouble() * 3.0D);
        int z = MathHelper.floor(entity.posZ - 2.0D + random.nextDouble() * 4.0D);
        BlockPos blockpos = new BlockPos(x, y, z);
        RayTraceResult ray = world.rayTraceBlocks(
                new Vec3d(MathHelper.floor(entity.posX) + 0.5f, y + 0.5f, MathHelper.floor(entity.posZ) + 0.5F), 
                new Vec3d(x + 0.5f, y + 0.5F, z + 0.5F), false, true, false);
        if(ray != null && ray.getBlockPos().equals(blockpos))
        {
            world.setBlockToAir(blockpos);
        }
    }
}