iw3xo/rtx - a Call of Duty 4 modification

This client mod brings various modifications and additions to the base game
and also includes support for nvidia's RTX Remix.

         

[ Most noteworthy features of iw3xo ]
map exporting -- live link between the game and radiant -- sp map loading in mp --
collision visualization -- day and night cycle with custom sky shader --
custom movement options and much more

[ Remix compatibility ]
tweak sunlight, fog and skybox per map -- spawning of unique anchor meshes to attach new prims --
remix friendly culling and the ability to override culling per portal --
3D is fully rendered with fixed-function

> Features / Guides / In-Depth <

https://xoxor4d.github.io/projects/iw3xo/

Usage

Mandatory but might not feature the latest and greatest:

1. Download the latest iw3xo release - the _rtx build comes with all files required for rtx remix

• Extract the contents into your cod4 root directory.
• Skip to Step 5 if you are not interested in nightly builds

Nightly (always up-to-date):

2. [rtx only] Install the latest full rtx-remix release (0.4.1 at this time)
   https://github.com/NVIDIAGameWorks/rtx-remix/tags

3. [rtx only] [optional] Install the latest github action builds of:
   remix bridge - https://github.com/NVIDIAGameWorks/bridge-remix/actions
   remix runtime - https://github.com/NVIDIAGameWorks/dxvk-remix/actions

4. Download the latest iw3xo (develop branch) github actions build:
   Build-Release - https://github.com/xoxor4d/iw3xo-dev/actions

• Drop iw3x.dll and the contents of the assets-remix folder [rtx only] into your cod4 root directory

5. Run run_remix.bat to start the game with rtx-remix features enabled
   or directly run iw3xo.exe

iw3xo.exe (modified to load iw3x.dll instead of d3d9.dll)
| -> iw3x.dll is a proxy d3d9.dll

6. Read the Dvars / Console Commands and Current issues sections

Remix section

🔷 To clarify, this client mod is only making CoD4 compatible with remix. 🔷

🔷 It does not enhance materials or meshes 🔷

My actual remix-mod with enhanced materials, meshes and lights can be found over at ModDB:
https://www.moddb.com/mods/cod4-mp-rtx-remix-iw3xo

• Use console command /devgui to open a developer gui -> RTX tab

  I suggest binding the /devgui command to a key, eg: /bind F5 devgui

• A. Commandline Arguments:

  • -rtx :: enable rtx modules (⚠️ required for rtx-remix)
  • -no_default_sky :: disable sky spawning (map settings)
  • -no_sun :: disable sun spawning (map settings)
  • -no_fog :: disable fog (map settings)
  • -stock_effects :: render effects using shaders
  • -old_anti_culling :: use the old anti culling system
  • -no_forced_lod :: do not set r_forceLod to high by default
  • -load_normal_spec :: enable loading of specular and normal maps (if you need to for some reason)
  • -no_playershadow :: disable player shadow casting

• commandline example:  c:\path\iw3xo.exe -rtx -no_default_sky -stock_effects

• B. Dvars (I recommend tweaking these via the /devgui) :

  🟩 encouraged to be tweaked
  🟦 can be useful in edge case scenarios
  🟧 shouldn't be touched

  Culling dvars:

  🟩 rtx_culling_tweak_mins :: prevents a bit of culling
  🟩 rtx_culling_tweak_maxs :: prevents a lot of culling
  🟩 rtx_culling_tweak_frustum :: disables frustum culling
  🟩 rtx_culling_tweak_smodel :: disables static model culling
  🟩 rtx_culling_plane_dist :: distance of frustum culling planes
  🟩 rtx_fx_cull_elem_draw_radius :: fx elements inside this radius around the player are not culled

  General dvars:

  🟩 r_forceLod :: force all models to a specific LOD
  🟩 r_forceLod_second_lowest :: prevent game from using the lowest LOD (sometimes used to hide the model)
  🟩 r_lodScaleRigid :: adjust static model draw distances (lower values increase draw distance)
  🟩 r_showTess :: draws material info (incl. all image names) of surfaces (geometry / models)
  🟩 r_showTessDist :: adjust draw distance of ^ info text
  🟩 r_showCellIndex :: show portal index info (useful for manual culling overrides via map settings)
  🟩 r_showModelNames :: draw names of static models around the player
  🟦 rtx_sky_hacks :: allows manually declaring textures as sky (maps w. multiple skies)
  🟦 rtx_sky_materials :: materials that iw3xo flags as 'sky' materials (logic that replaces the default sky)

  Dvars that should only be changed if you know what you are doing:

  🟧 rtx_warm_smodels :: build model vertex buffers on map load (enabled by default)
  🟧 rtx_hacks :: replace the skybox with a blue-gray texture
  🟧 rtx_extend_smodel_drawing :: disable static model draw limit (max amount of static models drawn at once)
  🟧 rtx_sky_follow_player :: sky will follow the player (helps with culling)
  🟧 rtx_fx_alpha_scalar :: global fx alpha scalar

  Culling dvars when old_anti_culling flag is set:

  🟩 rtx_disable_world_culling :: tweak overall culling
  🟩 rtx_disable_entity_culling :: tweak culling of script objects (entities)

• C. Console Commands :
  • mapsettings_update :: reload map settings
  • mapsettings_get_defaults :: prints sun direction, color and intensity in map_settings format based on the stock map settings to the consle

map_settings.ini :: root/iw3xo/rtx

🔸 Tweak sunlight / color, skybox and fog settings
🔸 Override culling per portal / cell (to fix light or shadow culling - dvar r_showCellIndex)
🔸 Spawn unique anchor meshes that can be used to attach unique prims and lights to

⚠️ Current Issues

• Swift changes in geometry (eg. teleporting) can crash the game.

  • Decrease geometry drawing by increasing culling or play with r_lodScaleRigid

• Remix might try to use your onboard gpu (that is a general CoD issue), so its best to disable it in the bios or within the device manager

• Some effects will slow down the game (really depends on the effect and the amount)

Questions?

• join the rtx-remix showcase discord and check out the cod4 thread within the remix-projects channel.
• join the iw3xo discord if you have questions related to iw3xo
• sp compatibility mod: iw3sp-mod-rtx
• rtx-remix: https://github.com/NVIDIAGameWorks/rtx-remix

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Requirements:

1. CoD4 1.7
2. English localization (other languages work when renamed)

• root/localization.txt   -> change first line to "english"
• root/main/   -> rename "localized_yourlanguage_iw**.iwd" files to "localized_english_iw**.iwd"
• root/zone/   -> rename folder "yourlanguage" to "english"

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Build / Compile

> How to build / compile the project using Visual Studio

1. Clone the repo! (zip does not include deps!)
2. Setup a COD4_ROOT environment variable with a path to your cod4 directory (optional)
3. Use generate-buildfiles.bat to build project files with premake
4. Open (build/iw3xo-dev.sln) and setup paths for the iw3x project (not needed if Step #2)

• General       output directory path -> path-to-cod4-root\
• Debugging   command -> path-to-cod4-root\iw3xo.exe
• Debugging   working directory -> path-to-cod4-root

4. Build -> Build Solution or run with debugger

Optional (Fastfile sources)

5. https://github.com/xoxor4d/xcommon_iw3xo (compiled, placed into root/zone/english/)
6. https://github.com/xoxor4d/xcommon_iw3xo_menu (compiled, placed into root/zone/english/)

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Optional:
https://github.com/xoxor4d/iw3xo-radiant

Project Page:
https://xoxor4d.github.io/projects/iw3xo/

Discord:
https://discord.gg/t5jRGbj

Credits

• X Labs (especially Snake)
• The Plutonium Project Team (especially Rektinator)
• Nukem9 - LinkerMod
• g-truc - glm
• ocornut - Dear ImGui
• Jelvan1 - cgame proxymod
• Nvidia - rtx-remix
• people of the rtx showcase discord (for testing, feedback and ideas)

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Disclaimer

This software has been created purely for the purposes of academic research. Project maintainers are not responsible or liable for misuse of the software. Use responsibly.