Virtual File Systems

Virtual Disk Files (or VDFs) are container files like ZIP or, more accurately TAR. A VDF contains a directory structure with multiple files within it. Originally, Gothic and Gothic II used a library called PhysicsFS to load these files and read from them. While PhysicsFS now supports VDFs out-of-the-box, ZenKit implements its own, modern parser for them. This page provides a high-level overview of the VDF implementation in ZenKit.

The original VDF implementation shipped with Gothic and Gothic II was not written by Piranha Bytes themselves but by a now defunct company called TRIACOM Software.

Overview

Using Virtual File Systems

CC++C#JavaPython

Example

#include <zenkit-capi/Vfs.h>

#include <stdio.h>

int main(int, char**) {
    ZkVfs* vfs = ZkVfs_new();
    ZkVfs_mountDiskHost(vfs, "Worlds.vdf", ZkVfsOverwriteBehavior_OLDER);

    ZkVfsNode* node = ZkVfs_findNode(vfs, "OLDWORLD.ZEN");
    if (node == NULL) {
        printf("Error: OLDWORLD.ZEN not found!\n");
        return -1;
    }

    ZkRead* rd = ZkVfsNode_open(node);
    // ...
    ZkRead_del(rd);
    ZkVfs_del(vfs);

    return 0;
}

Example

#include <zenkit/Vfs.hh>
#include <zenkit/Stream.hh>

#include <iostream>

int main(int, char const** argv) {
    zenkit::Vfs vfs {};
    vfs.mount_disk("Worlds.vdf");

    zenkit::VfsNode* node = vfs.find("OLDWORLD.ZEN");
    if (node == nullptr) {
        std::cerr << "Error: OLDWORLD.ZEN not found!\n";
        return -1;
    }

    std::unique_ptr<zenkit::Read> r = node->open_read();

    // ...

    return 0;
}

Example

using ZenKit;

var vfs = new Vfs();
vfs.MountDisk("Worlds.vdf", VfsOverwriteBehavior.Older);

VfsNode? node = vfs.Find("OLDWORLD.ZEN");

if (node == null)
{
    Console.Error.WriteLine("Error: OLDWORLD.ZEN not found!");
    return;
}

Read rd = node.Buffer;

// ...

Example

import dev.gothickit.zenkit.vfs.Vfs;
import dev.gothickit.zenkit.vfs.VfsNode;
import dev.gothickit.zenkit.vfs.VfsOverwriteBehavior;
import dev.gothickit.zenkit.Read;

var vfs = new Vfs();
vfs.mountDisk("Worlds.vdf", VfsOverwriteBehavior.OLDER);

VfsNode node = vfs.find("OLDWORLD.ZEN");

if (node == null)
{
    System.err.println("Error: OLDWORLD.ZEN not found!");
    return;
}

Read rd = node.open();

// ...

Example

from sys import stderr
from zenkit import Vfs, VfsOverwriteBehavior

vfs = Vfs()
vfs.mount_disk("Worlds.vdf", clobber=VfsOverwriteBehavior.OLDER)

node = vfs.find("OLDWORLD.ZEN")
if node is None:
    print("Error: OLDWORLD.ZEN not found!", file=stderr)
    exit(-1)

rd = node.open()

# ...