Unpacking GCF and VPK Files

Posted Mar 3, 2015
Last Updated Mar 13, 2017

Important Note: As of WW 3.04, you generally do not need to extract models, materials or textures as long as you are using 3ds Max 2015+. For the latest WW and Max 2015+, WW can natively load MDL, VMT and VTF files directly from the game and the VPK files. The information below is largely for older versions of Max.


For the most part the assets inside of Source Engine games are stores in GCF and VPK files. In order to use those inside Max 2014 and older, you'll need to extract them with a program called GCFScape; (as noted above, this isn't necessary for Max 2015+). If you don't have Wall Worm Pro, you'll also need VTFEdit to convert all the VTF files to TGA. And to use your models, you'll need Crowbar. Links for all are below.

Extract Content

  1. Create a folder on your computer that will store all of your raw game assets. Make sure that folder is writable. Later we will refer to this as your RAW directory. You can also skip creating this and instead simply use your mod's SDK Content folder as the RAW folder. But read the hints below.
  2. Download & Install GCFScape.
  3. Open GCFScape and open the Directory VPK file for the assets you want to extract. Different games/mods have different structures. For CS:GO, you open the pak01_dir.vpk to see all assets. For other mods, there are multiple directory VPK for different types of assets.
  4. Extract the folders from the VPK to your RAW directory. If all you are interested in is materials for brushes, extract just the materials folder. If you also want to use models, extract the models folder as well.
  5. Open the Wall Worm Settings and set the MatGen path to the materials folder inside your RAW directory.
  • If re-using your SDK Content folder as your content folder, be aware that it is possible that your original SMD/QC files can get overwritten if the paths/names already exist. Using the SDK content folder is actually the easiest method for re-using assets but you must remember the possible risk.

Convert Bitmaps

If you do not have Wall Worm Pro installed, you will need to convert the VTF Files into TGA files.

Convert the VTF files to TGA in VTFEdit by clicking Tools > Convert Folder in VTFEdit and the Output set as To tga From *.vtf. If you do not do this, no textures will import. Wall Worm Pro has native VTF support.

Now the Material Library Generator can be used to create libraries of materials from the Source materials and the VMF Importer can generate materials when importing scenes and the QC Importer can get materials when importing models.

Convert the MDL Files (Models)

At this time, there is now a native MDL viewer inside Max. That MDL loader only works in 3ds Max 2015. If you have 3ds Max 2015+ and the latest Wall Worm, you do not need to decompile any models. This section is only for 3ds Max 2014 and older. Skip this section if you have 3ds Max 2015+ (but make sure you have WW 2.915+.

The instructions for decompiling is dependent on your version of Crowbar. The preferred version is 0.26+. If you have an older version, you should update it. Get Crowbar here.

  • Decompiled models are not guaranteed to work exactly as the originals. There may be information that was lost during the original compile process. Do not be suprised if you sometimes have to edit a decompiled model.

Crowbar 0.26 +

  1. Create a folder inside the RAW directory named modelsrc.
  2. Open Crowbar and open the Decompiler Tab.
  3. Set the Output Folder to the Full Path option and use the modelsrc path you created above.
  4. Check/uncheck the Options per your needs. Those settings you absolutely need are QC File and Reference mesh SMD file. (If you are only using the props for re-use in your levels, you do not need the other options. Also, games like CS:GO no longer use LOD meshes, so unchecking that can speed up the process and take up less hard drive space.)
  5. Change the Folder drop-down menu to Folder and Subfolders.
  6. Click the Decompile button.
Importing Source Assets

This series covers the steps needed to re-use Source assets inside of 3ds Max.

  1. Unpacking GCF and VPK Files
  2. SMD, VTA and QC Importer
  3. Prop Libraries
  4. Using Props in Your Scene