_____                _____         _     _____            _            
|  _  |              |_   _|       | |   |  ___|          (_)           
| | | |_ __   ___ _ __ | | ___  ___| |__ | |__ _ __   __ _ _ _ __   ___ 
| | | | '_ \ / _ | '_ \| |/ _ \/ __| '_ \|  __| '_ \ / _` | | '_ \ / _ \
\ \_/ | |_) |  __| | | | |  __| (__| | | | |__| | | | (_| | | | | |  __/
 \___/| .__/ \___|_| |_\_/\___|\___|_| |_\____|_| |_|\__, |_|_| |_|\___|
      | |                                             __/ |             
      |_|                                            |___/ 

Thank you for downloading OpenTechEngine.

OpenTechEngine is idTech based engine, forked from RBDOOM-3-BFG.

---

CONTENTS

---

This file contains the following sections:

1) SYSTEM REQUIREMENT

2) GENERAL NOTES

3) LICENSE

4) GETTING THE SOURCE CODE

5) COMPILING ON WIN32 WITH VISUAL C++ 2013 EXPRESS EDITION

6) COMPILING ON GNU/LINUX

7) INSTALLATION, GETTING THE GAMEDATA, RUNNING THE GAME

8) CHANGES

9) CONSOLE VARIABLES

10) KNOWN ISSUES

11) BUG REPORTS

---

1. SYSTEM REQUIREMENTS

---

Minimum system requirements:

CPU: 2 GHz Intel compatible
System Memory: 512MB
Graphics card: Any graphics card that supports Direct3D 10 and OpenGL >= 3.2

Recommended system requirements:

CPU: 3 GHz + Intel compatible
System Memory: 1024MB+
Graphics card: Geforce 9600 GT, ATI HD 5650 or higher. 

---

2. GENERAL NOTES

---

This release does not contain any game data, the game data is still covered by the original EULA and must be obeyed as usual.

You must patch the game to the latest version.

Note that Doom 3 BFG Edition is available from the Steam store at http://store.steampowered.com/app/208200/

Steam:

The Doom 3 BFG Edition GPL Source Code release does not include functionality for integrating with Steam. This includes roaming profiles, achievements, leaderboards, matchmaking, the overlay, or any other Steam features.

Bink:

The OpenTechEngine GPL Source Code release includes functionality for rendering Bink Videos through FFmpeg.

Back End Rendering of Stencil Shadows:

The Doom 3 BFG Edition GPL Source Code release does not include functionality enabling rendering of stencil shadows via the "depth fail" method, a functionality commonly known as "Carmack's Reverse".

Mods:

The Doom 3 BFG Edition GPL Source Code release allow mod editing, in order for it to accept any change in your mod directory, you should first specify your mod directory adding the following command to the launcher:

"+set fs_game modDirectoryName"

as well as force the content of your mod directory over the content of the game with the following command:

"+set fs_resourceLoadPriority 0"

so it would end up looking like: OpenTechEngine +set fs_resourceLoadPriority 0 +set fs_game mymod

---

3. LICENSE

---

Most code and the shaders are licensed under a slightly modified GPLv3 license.
Most assets in base/ are released under WTFPLv2 or similar Public Domain licenses.

See COPYING.md for details and COPYING-GPLv3-id.txt for the modified GPLv3 license text.

ADDITIONAL TERMS: The Doom 3 BFG Edition GPL Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU GPL which accompanied the Doom 3 BFG Edition GPL Source Code. If not, please request a copy in writing from id Software at id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

---

4. GETTING THE SOURCE CODE

---

This project's GitHub.net Git repository can be checked out through Git with the following instruction set:

> git clone --recurse-submodules https://github.com/OpenTechEngine/OpenTechBFG.git

Don't forget "--recurse-submodules" it initialises the cegui submodule and downloads it for you.

If you don't want to use git, you can download the source as a zip file at https://github.com/OpenTechEngine/OpenTechBFG/archive/master.zip

---

5. COMPILING ON WIN32 WITH VISUAL C++ 2013 EXPRESS EDITION

---

1. Download and install the Visual C++ 2013 Express Edition.

2. Download the DirectX SDK (June 2010) here: http://www.microsoft.com/en-us/download/details.aspx?id=6812

3. Download and install the latest CMake.

4. Generate the VC13 projects using CMake by doubleclicking a matching configuration .bat file in the neo/scripts folder.

5. Use the VC13 solution to compile what you need: OpenTechEngine/build/OpenTechEngine.sln

6. Download ffmpeg-20140405-git-ec8789a-win32-shared.7z from ffmpeg.zeranoe.com/builds/win32/shared

7. Extract the FFmpeg DLLs to your current build directory under OpenTechEngine/build/

---

6. COMPILING ON GNU/LINUX

---

1. You need the following dependencies in order to compile OpenTechEngine with all features:

   On Debian or Ubuntu:

    > apt-get install cmake libsdl1.2-dev libopenal-dev libavcodec-dev libavformat-dev libavutil-dev libswscale-dev
   

   On Fedora

    // TODO add ffmpeg libs for bink videos
    
    > yum install cmake SDL-devel openal-devel
   

   On ArchLinux

    > sudo pacman -S sdl ffmpeg openal cmake  
   
    Alternatively you can install sdl2 instead of sdl.
   

   On openSUSE (tested in 13.1)

    > zypper in openal-soft-devel cmake libSDL-devel libffmpeg1-devel
   
    For SDL 2 replace "libSDL-devel" with "libSDL2-devel".
    "libffmpeg1-devel" requires the PackMan repository. If you don't have that repo, and don't want to add it, remove the "libffmpeg1-devel" option and compile without ffmpeg support.
    If you have the repo and compiles with ffmpeg support, make sure you download "libffmpeg1-devel", and not "libffmpeg-devel".
   

   Instead of SDL1.2 development files you can also use SDL2. Install SDL 2.0 and add to the cmake parameters -DSDL2=ON

   SDL2 has better input support (especially in the console) and better support for multiple displays (especially in fullscreen mode).

2. Generate the Makefiles using CMake:

   cd scripts
   ./cmake-eclipse-linux-profile.sh

3. Compile OpenTechEngine targets with

   cd ../build make

---

7. INSTALLATION, GETTING THE GAMEDATA, RUNNING THE GAME

---

If you use the prebuilt Win32 binaries then simply extract them to your C:\Program Files (x86)\Steam\SteamApps\common\Doom 3 BFG Edition\ directory and run OpenTechEngine.exe.

The following instructions are primarily intented for Linux users and all hackers on other operating systems.

To play the game, you need the game data from a legal copy of the game, which unfortunately requires Steam for Windows - Steam for Linux or OSX won't do, because (at least currently) the Doom 3 BFG game is only installable on Steam for Windows. Even the DVD version of Doom 3 BFG only contains encrytped data that is decoded by Steam on install.

On Linux and OSX the easiest way to install is with SteamCMD: https://developer.valvesoftware.com/wiki/SteamCMD See the description on https://developer.valvesoftware.com/wiki/SteamCMD#Linux (OS X is directly below that) on how to install SteamCMD on your system. You won't have to create a new user.

Then you can download Doom 3 BFG with

./steamcmd.sh +@sSteamCmdForcePlatformType windows +login <YOUR_STEAM_LOGIN_NAME> +force_install_dir ./doom3bfg/ +app_update 208200 validate +quit

(replace <YOUR_STEAM_LOGIN_NAME> with your steam login name)
When it's done you should have the normal windows installation of Doom 3 BFG in ./doom3bfg/ and the needed files in ./doom3bfg/base/
That number is the "AppID" of Doom 3 BFG; if you wanna use this to get the data of other games you own, you can look up the AppID at https://steamdb.info/

NOTE that we've previously recommended using download_depot in the Steam console to install the game data. That turned out to be unreliable and result in broken, unusable game data. So use SteamCMD instead, as described above.

Anyway:

1. Install Doom 3 BFG in Steam (Windows version) or using SteamCMD, make sure it's getting updated/patched.

2. Create your own Doom 3 BFG directory, e.g. /path/to/Doom3BFG/

3. Copy the game-data's base dir from Steam to that directory (e.g. /path/to/Doom3BFG/), it's in /your/path/to/Steam/steamapps/common/DOOM 3 BFG Edition/base/ or, if you used SteamCMD, in the path you used above.

4. Copy your OpenTechEngine executable that you created in 5) or 6) and the FFmpeg DLLs to your own OpenTechEngine directory (/path/to/OpenTechEngine/).

   Your own Doom 3 BFG directory now should look like: /path/to/Doom3BFG/ -> OpenTechEngine (or OpenTechEngine.exe on Windows) -> avcodec-55.dll -> avdevice-55.dll -> avfilter-4.dll -> avformat-55.dll -> avutil-52.dll -> postproc-52.dll -> swresample-0.dll -> swscale-2.dll -> base/ -> classicmusic/ -> _common.crc -> (etc)

5. Run the game by executing the OpenTechEngine executable.

6. Enjoy

7. If you run into bugs, please report them, see 11)

---

8. CHANGES

---

• Flexible build system using CMake

• Linux support (32 and 64 bit)

• Win64 support

• OS X support

• OpenAL Soft sound backend primarily developed for Linux but works on Windows as well

• Bink video support through FFmpeg

• Soft shadows using PCF hardware shadow mapping

  The implementation uses sampler2DArrayShadow and PCF which usually requires Direct3D 10.1 however it is in the OpenGL 3.2 core so it should be widely supported. All 3 light types are supported which means parallel lights (sun) use scene independent cascaded shadow mapping. The implementation is very fast with single taps (400 fps average per scene on a GTX 660 ti OC) however I defaulted it to 12 taps using a Poisson disc algorithm so the shadows look really good which should give you stable 100 fps on todays hardware (2014).

• Changed light interaction shaders to use Half-Lambert lighting like in Half-Life 2 to make the game less dark. https://developer.valvesoftware.com/wiki/Half_Lambert

• True 64 bit HDR lighting with adaptive tone mapping and gamma-correct rendering in linear RGB space

• Enhanced Subpixel Morphological Antialiasing For more information see "Anti-Aliasing Methods in CryENGINE 3" and the docs at http://www.iryoku.com/smaa/

• Filmic post process effects like Technicolor color grading and film grain

• Additional ambient render pass to make the game less dark similar to the Quake 4 r_forceAmbient technique

---

9. CONSOLE VARIABLES

---

r_antiAliasing - Different Anti-Aliasing modes

r_useShadowMapping 1 - Use soft shadow mapping instead of hard stencil shadows

r_useHDR [0 or 1] - Use High Dynamic Range lighting

r_hdrAutoExposure [0 or 1] - Adaptive tonemapping with HDR This allows to have very bright or very dark scenes but the camera will adopt to it so the scene won't loose details

r_exposure [0 .. 1] - Default 0.5, Controls brightness and affects HDR exposure key This is what you change in the video brightness options

r_useSSAO [0 .. 1] - Use Screen Space Ambient Occlusion to darken the corners in the scene

r_useFilmicPostProcessEffects [0 or 1] - Apply several post process effects to mimic a filmic look"

---

10. KNOWN ISSUES

---

Doom 3 wasn't designed to work with shadow maps so:

• Some lights cause shadow acne with shadow mapping
• Some shadows might almost disappear due to the shadow filtering

Also keep in mind following things:

• HDR does not work with old-school stencil shadows

• MSAA anti-aliasing modes don't work with HDR: Use SMAA

---

11. BUG REPORTS

---

OpenTechEngine is not perfect, it is not bug free as every other software. For fixing as much problems as possible we need as much bug reports as possible. We cannot fix anything if we do not know about the problems.

The best way for telling us about a bug is by submitting a bug report at our GitHub bug tracker page:

https://github.com/OpenTechEngine/OpenTechBFG/issues?state=open
And our fork source at
https://github.com/RobertBeckebans/RBDOOM-3-BFG/issues?state=open

The most important fact about this tracker is that we cannot simply forget to fix the bugs which are posted there. It is also a great way to keep track of fixed stuff.

If you want to report an issue with the game, you should make sure that your report includes all information useful to characterize and reproduce the bug.

* Search on Google
* Include the computer's hardware and software description ( CPU, RAM, 3D Card, distribution, kernel etc. )
* If appropriate, send a console log, a screenshot, an strace ..
* If you are sending a console log, make sure to enable developer output:

          OpenTechEngine.exe +set developer 1 +set logfile 2

NOTE: We cannot help you with OS-specific issues like configuring OpenGL correctly, configuring ALSA or configuring the network.