过去几天，我一直在研究一种方法，可以在保存时将我的 xna 游戏的 1.44 亿个图 block 表示压缩到非常小的尺寸。成功完成后，我现在发现自己对如何从文件中分块取回它们感到困惑。
在我的文件中。
- 一个整数(使用 7BitEncodedInt 方法将其压缩为字节)
- 一个字节
压缩后的整数表示瓦片的数量，后面的字节决定瓦片的类型。这一切都很好，而且效果很好。最重要的是，它将文件大小平均缩小到仅 50mb。
问题是我目前正在读回整个文件。 我从文件中得到这个。
- 每个图 block 的索引值(只是我抓取图 block 时的基本迭代)
- 每个图 block 的类型作为字节值
- 表示该图 block 纹理的字节值(这很难解释，但对每个图 block 而言都是必需的)
所有这一切的最终结果是我设法保存了文件并且只使用了大约 50mb。但是通过将整个东西加载回去，它在 ram 上扩展到近 1.5gigs。我真的不能再牺牲磁贴信息了。所以我需要一种方法来根据玩家位置只加载 map 的一部分。目标是在 100-200mb 范围内
我一直在研究文件的内存映射，使用四叉树，几乎所有我能找到的用于分块加载文件的东西。虽然这些选项看起来都不错，但我不确定哪个是最好的，或者如果考虑到这种情况，可能还有另一个更好的选项。所有这一切的另一个问题是，这些解决方案似乎都非常复杂(尤其是因为这是我第一次使用它们)，虽然我不反对将自己投入到一些冗长的编码中，但我想知道它会做我想做的事事先需要它。
我的问题是，考虑到我在拉入文件时必须如何处理文件，以及需要根据玩家位置完成此操作的事实，最好的方法是什么？我只是在这里寻找一些方向。代码总是受欢迎的，但不是必需的。
最佳答案
您想在 Tile 类中使用固定长度的变量并实现如下内容:
这是一个集合类 (People) 的示例，它可以根据索引从序列化到文件中的集合中获取值。
Person 是 People 集合的基础类。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace FileStreamDatabaseTest
{
class Program
{
static void Main(string[] args)
{
People.OpenCollection();
People.Test_WillOverwriteData();
People.CloseCollection();
Console.ReadLine();
}
}
public class Person
{
// define maxium variable sizes for serialisation
protected static int pMaxLength_FirstName = 64;
protected static int pMaxLength_Age = 10;
public static int MaxObjectSize
{
get
{
// return the sum of all the maxlegnth variables to define the entire object size for serialisation
return pMaxLength_FirstName + pMaxLength_Age;
}
}
// define each object that will be serialised as follows
protected string pFirstName;
public string Firstname
{
set
{
// ensure the new value is not over max variable size
if (value.Length > pMaxLength_FirstName)
throw new Exception("the length of the value is to long.");
pFirstName = value;
}
get
{
return pFirstName;
}
}
protected int pAge;
public int Age
{
get
{
return pAge;
}
set
{
pAge = value;
}
}
public byte[] Serialise()
{
// Output string builder
StringBuilder Output = new StringBuilder();
// Append firstname value
Output.Append(Firstname);
// Add extra spaces to end of string until max length is reached
if (Firstname.Length < pMaxLength_FirstName)
for (int i = Firstname.Length; i < pMaxLength_FirstName; i++)
Output.Append(" ");
// Append age value as string
Output.Append(Age.ToString());
// Add extra spaces to end of string until max length is reached
int AgeLength = Age.ToString().Length;
if (AgeLength < pMaxLength_Age)
for (int i = AgeLength; i < pMaxLength_Age; i++)
Output.Append(" ");
// Return the output string as bytes using ascii encoding
return System.Text.Encoding.ASCII.GetBytes(Output.ToString());
}
public void Deserialise(byte[] SerialisedData)
{
string Values = System.Text.Encoding.ASCII.GetString(SerialisedData);
pFirstName = Values.Substring(0, pMaxLength_FirstName).Trim();
pAge = int.Parse(Values.Substring(pMaxLength_FirstName, pMaxLength_Age).Trim());
}
}
public static class People
{
private static string tileDatasource = @"c:\test.dat";
private static System.IO.FileStream FileStream;
public static void OpenCollection()
{
FileStream = new System.IO.FileStream(tileDatasource, System.IO.FileMode.OpenOrCreate, System.IO.FileAccess.ReadWrite, System.IO.FileShare.None);
}
public static void CloseCollection()
{
FileStream.Close();
FileStream.Dispose();
FileStream = null;
}
public static void SaveCollection(Person[] People)
{
FileStream.SetLength(People.Length * Person.MaxObjectSize);
FileStream.Position = 0;
foreach (Person PersonToWrite in People)
{
// call serialise to get bytes
byte[] OutputBytes = PersonToWrite.Serialise();
// write the output buffer
// note: this will always be the same size as each variable should
// append spaces until its max size is reached
FileStream.Write(OutputBytes, 0, OutputBytes.Length);
}
}
public static Person GetValue(int Index)
{
// set the stream position to read the object by multiplying the requested index with the max object size
FileStream.Position = Index * Person.MaxObjectSize;
// read the data
byte[] InputBytes = new byte[Person.MaxObjectSize];
FileStream.Read(InputBytes, 0, Person.MaxObjectSize);
// deserialise
Person PersonToReturn = new Person();
PersonToReturn.Deserialise(InputBytes);
// retun the person
return PersonToReturn;
}
public static void Test_WillOverwriteData()
{
long StartTime;
long EndTime;
TimeSpan TimeTaken;
Console.WriteLine("-------------------------------------------------------------------");
Console.WriteLine("*** Creating 2,000,000 test people... ");
StartTime = DateTime.Now.Ticks;
Person[] People = new Person[2000000];
for (int i = 0; i < 2000000; i++)
{
People[i] = new Person();
People[i].Firstname = "TestName." + i;
People[i].Age = i;
}
EndTime = DateTime.Now.Ticks;
TimeTaken = new TimeSpan(EndTime - StartTime);
Console.WriteLine("-> Completed in " + TimeTaken.TotalSeconds + " seconds");
Console.WriteLine("-------------------------------------------------------------------");
Console.WriteLine("*** Serialising Collection to disk... ");
StartTime = DateTime.Now.Ticks;
SaveCollection(People);
EndTime = DateTime.Now.Ticks;
TimeTaken = new TimeSpan(EndTime - StartTime);
Console.WriteLine("-> Completed in " + TimeTaken.TotalSeconds + " seconds");
Console.WriteLine("-------------------------------------------------------------------");
Console.WriteLine("*** Redundancy Test... ");
StartTime = DateTime.Now.Ticks;
bool Parsed = true;
int FailedCount = 0;
for (int i = 0; i < 2000000; i++)
{
if (GetValue(i).Age != i)
{
Parsed = false;
FailedCount++;
}
}
EndTime = DateTime.Now.Ticks;
TimeTaken = new TimeSpan(EndTime - StartTime);
Console.WriteLine("-> " + (Parsed ? "PARSED" : "FAILED (" + FailedCount + " failed index's"));
Console.WriteLine("-> Completed in " + TimeTaken.TotalSeconds + " seconds");
Console.WriteLine("-------------------------------------------------------------------");
Console.WriteLine("*** Reading 10,000 index's at once... ");
StartTime = DateTime.Now.Ticks;
Person[] ChunkOfPeople = new Person[10000];
for (int i = 0; i < 10000; i++)
ChunkOfPeople[i] = GetValue(i);
EndTime = DateTime.Now.Ticks;
TimeTaken = new TimeSpan(EndTime - StartTime);
Console.WriteLine("-> Completed in " + TimeTaken.TotalSeconds + " seconds");
Console.WriteLine("-------------------------------------------------------------------");
Console.WriteLine("*** Reading 100,000 index's at once... ");
StartTime = DateTime.Now.Ticks;
ChunkOfPeople = new Person[100000];
for (int i = 0; i < 100000; i++)
ChunkOfPeople[i] = GetValue(i);
EndTime = DateTime.Now.Ticks;
TimeTaken = new TimeSpan(EndTime - StartTime);
Console.WriteLine("-> Completed in " + TimeTaken.TotalSeconds + " seconds");
Console.WriteLine("-------------------------------------------------------------------");
Console.WriteLine("*** Reading 1,000,000 index's at once... ");
StartTime = DateTime.Now.Ticks;
ChunkOfPeople = new Person[1000000];
for (int i = 0; i < 1000000; i++)
ChunkOfPeople[i] = GetValue(i);
EndTime = DateTime.Now.Ticks;
TimeTaken = new TimeSpan(EndTime - StartTime);
Console.WriteLine("-> Completed in " + TimeTaken.TotalSeconds + " seconds");
}
}
}
关于c# - 请求分块加载我的文件的方向(只需要建议)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/6352816/