using System;

using System.Collections.Generic;

​

public class Program

{

    public class Chunk{

        public string Nome;

    }

    public static void Main()

    {

        var dict = new IntPosDictionary<Chunk>();

        var chunk = new Chunk();

        chunk.Nome = "teste1";

        dict.Add(1,2,3,chunk);

        dict.Add(1,2,1,new Chunk(){Nome="teste2"});

        //Dois jeitos de recuperar

        // Direto

        Console.WriteLine(dict[1][2][3].Nome);

        // Pela função

        Console.WriteLine(dict.GetAtPos(1,2,3).Nome);

        Console.WriteLine(dict.GetAtPos(1,2,1).Nome);

    }

    public class IntPosDictionary<T> : Dictionary<int,Dictionary<int, Dictionary<int, T>>>{     

        public T Value(int x,int y,int z = 0){

            return this[x][y][z];

        }

        public void Add(int x,int y,int z,T value){

            Dictionary<int, Dictionary<int, T>> dictY;

            Dictionary<int, T> dictZ;

            if(this.ContainsKey(x)){

                dictY = this[x];// Pego o dicionario de Y

                if(dictY.ContainsKey(y)){

                    dictZ = dictY[y]; // Pego dicionario Z                  

                }else{

                    dictZ = new Dictionary<int, T>();// esse Y não tem, crio ele e o dicionario Z

                }

            }else{ // X nunca atribuido crio ele e o dicionaryo Y e Z

                dictY = new Dictionary<int, Dictionary<int, T>>();

                dictZ = new Dictionary<int, T>();

                dictZ.Add(z,value);

                dictY.Add(y,dictZ);

                this.Add(x,dictY);

            }

            if(!dictZ.ContainsKey(z)){

                dictZ.Add(z,value);

            }

        }

        public T GetAtPos(int x,int y,int z){

            return this[x][y][z];

        }

    }

}