Unpacking Your Pack

Half-Life stores the majority of it's content in PAK files. The PAK file is an archive that contains files in a specific directory structure that the game can read from.

For editing purposes, it is most preferable when some or all of a PAK's contents is "unpacked" - that is, that the contents reside in their normal directory structure rather than inside the PAK file.

There are a number of benefits to having the PAK file.

• easy access to sounds, sprites, and model files.
  

• for mod makers, easy to add and remove contents
  
• makes it possible to "browse" for content in the editor's entity properties, where applicable
  
• make it possible for the editor to display sprites in the 3D view (Hammer does not read out of the PAK file)

The first thing you need is a program capable of browsing and editing the PAK file. Wally is a good tool for this, since it's also a fantastic texture editor and is freely available. You can get Wally from it's website, here -

http://www.telefragged.com/wally/

Unpacking
Unpacking PAK contents is pretty simple. The following example shows how to unpack the Sprite folder.

1. Load Wally and click on Open in the File menu. Browse to the Half-Life folder. Double-click on the valve folder. Click on pak0.pak and press the Open button.
   

2. A window will open with the contents of the PAK file displayed. Right-click on the Sprites folder and select Export. In the Destination text box, browse to and select the valve folder inside your Half-Life folder.
   
3. Press the Ok button to extract the files.
   
4. That's it.

It's important to maintain the correct directory structure of files. If you're unpacking a PAK that is in a specific game directory, the unpacked files should be exported only to that game directory.