This is an implementation of the CPack file reader in C# using .NET Standard 2.1.
CPack(.cpk) is a file format used to store game assets in the game Pal3(仙剑奇侠传三) and Pal3a(仙剑奇侠传3外传-问情篇) created by Softstar Technology (Shanghai) Co., Ltd.
dotnet build// Example to load and open one file stored inside a CPK archive using Cpk.Net
using Cpk.Net;
const string CpkPath = "...";
const string VirtualFilePath = "..."; // Virtualized/relative file path within CPK archive
var cpk = new CpkArchive(CpkPath);
await cpk.LoadAsync();
await using var stream = cpk.Open(VirtualFilePath, out uint size, out bool isCompressed);
...// Example to load and upack all files stored inside a CPK archive using Cpk.Net
using Cpk.Net;
const string CpkPath = "...";
const string OutputFolderPath = "...";
var cpk = new CpkArchive(CpkPath);
await cpk.LoadAsync(loadIntoMemory: true);
var rootNodes = await cpk.GetRootEntriesAsync();
Unpack(rootNodes, OutputFolderPath);
void Unpack(IList<CpkEntry> nodes, string rootPath)
{
foreach (var node in nodes)
{
// You need to replace CPK directory separator char with
// your current system directory separator char.
// So this code can run anywhere.
var relativePath = node.VirtualPath.Replace(
CpkConstants.CpkVirtualDirectorySeparatorChar, Path.DirectorySeparatorChar);
if (node.IsDirectory)
{
new DirectoryInfo(rootPath + relativePath).Create();
Unpack(node.Children, rootPath);
}
else
{
using var readStream = cpk.Open(node.VirtualPath, out var size, out var isCompressed);
using var writeStream = new FileStream(rootPath + relativePath, FileMode.Create, FileAccess.Write);
CopyStream(readStream, writeStream, (int)size, isCompressed ? size : 32768);
Console.WriteLine($"{node.VirtualPath} unpacked.");
}
}
}
static void CopyStream(Stream input, Stream output, int length, uint bufferSize)
{
byte[] buffer = new byte[bufferSize];
int read;
while ((read = input.Read(buffer, 0, Math.Min(buffer.Length, length))) > 0)
{
output.Write(buffer, 0, read);
length -= read;
}
}MIT License
Copyright (c) 2022 Jiaqi Liu
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