Support for adding modified content to the game has been added after integrating Steam Workshop into the games.

This document describes guidelines, possibilities, mod creating process, information about available tools, uploading method and moderation.

Because of the new DX12 implementation the shaders should be separately pre-compiled by the external tool listed below.

Other than that - you can modify and change the big variety of the files through mods.

The types of files that can be modified:

• Animations
  
• Textures
  
• Models
  
• Videos
  
• Sounds
  
• Configs
  
• Scripts

Modification of any other file types (.dll libs and .exe binary file) is not allowed by the distributing platform standards and
the files will not be loaded by the game.

Because of the limitations on consoles and safety reasons, actual implementation of Mod.io SDK allows modifying only already existing files on consoles. It means that content like new models or sounds can be added to the games using the SDK only as a replacement for the already existing files. In other words, changes can only be introduced to currently used game files.
As for the PC mods - you’re free to modify all of the files listed below.

The types of files that can be modified:

• Animations
  
• Textures
  
• Models
  
• Videos
  
• Sounds
  
• Shaders (only on PC)

Modification of any other file types (.dll libs and .exe binary file) is not allowed by the distributing platform standards and
the files will not be loaded by the game.

Consoles special:

Modification of any other file types (like scripts, configs or libraries) is not allowed through https://mod.io/ and
the files will not be loaded by the game and accepted by moderation.

Modifications have size limitations for consoles - single modification cannot be bigger than 1GB in
unpacked version.

In order to create new mods modders have to use the same tools that they were
using to modify earlier versions of the games on PC.

The only difference is the way of
packing and installing modifications.

To mod the game the user needs:

• Stalker modding tools (Stalker SDK) from the original games,
  
• Sound editor software that can edit .ogg files (for example Audacity
software),
  
• 3D visual effects software (for example Maya),
  
• Image manipulation software (for example gimp or Photoshop),
  
• Video editing software.

To create mod package for PC, two tools and list of modifiable files are needed:

• File packer that allows to pack to .zip format (7-zip for example) Needed only for ModIO
  
• Provided xrCompress[modio.stalker-game.com] tool to prepare .pak files

First step is creating a proper file structure that corresponds to the original game files.


Example of the file structure

After preparing the structure, the user needs to launch the xrCompress[modio.stalker-game.com] tool(Pay attention as theres 2 set of xrCompressors made for http://mod.io and a separate one made for Steam Workshop) through the command console, with the path to the root of the mod added as a parameter.
The tool will generate .pak files that will be loaded by the game. The exceptions are .mp4 files that should not be packed and should be added to the modification archive in non-packed form. Packer must be unpacked to work. In order to launch it the user needs to open command prompt, open folder containing unpacked xrCompress[modio.stalker-game.com] and run it with command:
bin\xrCompress.exe <path_to_the_raw_mod_files> -store

Example command for packing mod files

After the compiler ends its task the packed files will be located in the folder below root of the modification (for example C:/mods when mod is stored in C:/mods/myMod).

Steam Workshop: Place the packed files in a separate folder without any other files than .pack or .mp4 extensions.
Here’s an example of file structure after packing:

—Mod_folder:
—textures\ui\video\example.mp4
—packed-mod.pack
—packed-mod.pack2

Mod.IO: These files need to be packed to a .zip file if you plan for the mod to be uploaded on mod.io servers. If any .mp4 file needs to be added to the mod then it should be added to the package maintaining the file structure.

To modify and compile the shaders you need:

• Shader instruments that contain shader examples and shader compiling tool for all 3 titles

Provided stk-shaders[modio.stalker-game.com] tool to prepare selected shaders

• Windows SDK with the latest libraries Windows SDK[developer.microsoft.com] to use dxc.exe (DirectX compiler)

1. Unpack the shaders tool in any short pathed folder for example (C:/stk-shaders/)
2. Locate the compile_shaders.cmd file inside of the shaders tool folder
3. Open it using any text editor and enter the proper path to dxc.exe that was installed with Win SDK, usually “C:\Program Files (x86)\Windows Kits\10\bin\10.0.22621.0\x64\dxc.exe”

Now you’re set to edit and compile shaders!

To compile the already existing shaders you need to open the stk-shaders\shaders\r4_dx12 folder, find the shader you want to modify and make changes to it.
Then you should generate a parameter config file for this exact shader with a cmd command
“filter_shader.cmd cop hud_font.ps” the example if for Call of pripyat title for hud_font.ps shader

Running the command from above will generate a “stk_cop_slist.txt” file in utils folder. It contains the name of the shader and all the proper parameters for it to be compiled.
You can modify multiple shaders at once for one title and use filter_shader.cmd to add all the modified shaders to the parameters list.

As for the shaders created from scratch - you will need to search for the proper parameters that it will require and manually modify the “stk_cop_slist.txt” for the proper shader variants to be created during compiling.

After all the modifications and “stk_cop_slist.txt” file generation you’re set to compile the shaders via CMD commands:

SteamWorkshop: “compile_shaders.cmd cop crc” - fits for direct mounting into the gamedata or for packing to SteamWorkshop mods via xrCompress[modio.stalker-game.com] tool.

ModIO: “compile_shaders.cmd cop as-is” - fits for ModIO mods packing via xrCompress[modio.stalker-game.com].

After compilation you can check the stk_cop.log file for the possible errors and the final compiled shaders can be found in ”objects\cop” folder and if they’re compiled with ”crc” options - you can test them by simply placing in "gamedata\shaders\r4_dx12\objects" folder of the corresponding title (cop,cs or soc). The shaders should apply on the title during the next boot.

After placing the modification packages into a separate folder, the user needs to launch the xrSWS_Upload[modio.stalker-game.com] tool from the root folder of any stalker trilogy game title. Simply drag-n-drop the xrSWS_Upload.exe into the game root folder and run it from the console to get the help details.

Example help command for uploading mods to workshop


steamapps\common\STALKER Call of Prypiat - EE\ >xrSWS_Upload.exe --mode=create --game=CS --path=<path_to_the_packed_mod_files_folder> --preview=<path_to_the_preview.jpg> --title="Here goes the mod title" --desc="Description text" --changelog="Changelog text"

Shortly after a successful mod creation - you can find it in your private mods in a workshop page:
Private mods for Stalker Call of Prypiat EE on steam workshop page

After preparing the modification package, the user needs to go to the Mod.io website using a browser, open a proper game and click the “add mod” button.
Main page of Stalker Call of Prypiat on mod.io site

Add your Mod window should be displayed. The user needs to fill all required fields like name of the mod, description and all other needed data and resources.
Add mod page on mod.io site

After that images of the modification should be chosen and uploaded. The last step is uploading the modification package and publishing the modification.
File managing page from one on sample mods on mod.io page

Lastly, the uploaded mod needs to be approved by the Publisher to be visible for users.

When modification is uploaded but not yet accepted only the author is able to see it and download it. This way the author will be able to test the modification before providing it to the public. The mod becomes available to other users once it is accepted by moderators.

All of the uploaded modifications are moderated by the Publisher who ensures that all available modifications meet the requirements and do not break the game. Moderators accept the uploaded modifications before being released, arbitrate user reports and take appropriate action towards modifications that break the terms or service.
To report modification users need to use the report button in the main menu or use the report button that’s present on the modification page.