OpenTomb — an open-source Tomb Raider 1-5 engine remake
Table of contents
- What is this?
- Why create a new engine?
- Supported platforms
- Running and Configuration
What is this?
OpenTomb is an open-source re-implementation of the classic Tomb Raider engine, intended to play levels from all classic-era Tomb Raider games (1—5), as well as custom TRLE levels. The project does not use any of the original Tomb Raider code, as all attempts to retrieve source files from Eidos/Core were in vain.
Instead, everything is being re-developed completely from scratch. It should be noted, however, that OpenTomb uses certain legacy routines from unfinished open-source projects, such as OpenRaider and VT project (found at icculus.org), plus some code from Quake Tenebrae.
OpenTomb tries to recreate the original Tomb Raider series experience, although with contemporary updates, features and additions, being able to fully benefit from running on modern PCs with powerful CPUs and graphic cards.
Links to forums and info:
- TR forum link: http://www.tombraiderforums.com/showthread.php?t=197508
- Discord channel: https://discord.gg/d8mQgdc
Why create a new engine?
It's true that we have fully working Windows builds of TR2-5, and TR1 works perfectly through DosBox. However, as time progresses the situation will only worsen, with newer Operating Systems becoming increasingly unlikely to support the games. OpenTomb will always be able to be ported to any platform you wish.
It is also true that there are patchers for the original engine, aiming to improve and update it: TREP, TRNG, etc. The advantage with OpenTomb is that we are not limited by the original Binary, a huge limitation when it comes to new features, graphical enhancements, code modification and more. An open-source engine removes these limitations.
- OpenTomb has a completely different collision approach to the original engine, circumventing many of the limitations present. We use a terrain generator to make an optimized collision mesh for each room from so-called "floordata".
- OpenTomb is capable of a variable frame rate, not limited to 30fps like the original engine.
- OpenTomb uses common and flexible libraries, such as OpenGL, OpenAL, SDL and Bullet Physics.
- OpenTomb implements a Lua scripting engine to define all entity functionality. This means that, again, unlike the original, much less is hardcoded into the engine itself, so functionality can be extended or modified without havng to modify and recompile the engine itself.
- Many abandoned and unused features from the original engine have been enabled in OpenTomb. New animation, unused items, hidden PSX-specific structures inside level files, and so on!
OpenTomb is a cross-platform engine: currently it can be ran on Windows, Mac or Linux. No mobile implementations are in development yet, but they are indeed possible.
To run any of the levels from the original games, you will need the assets from that respective game. These resources often tend to be in cryptic formats, with variations across games. Because of this, you'll need to convert some game resources to usable formats yourself, or get them from somewhere on the Net.
Here is the list of all needed assets and where to get them:
Data folders from each game. Get them from your retail game CDs or Steam/GOG bundles. Just take data folder from each game's folder, and put it into corresponding
/data/tr*/folder. For instance, for TR3, the path would be
CD audio tracks. OpenTomb only supports OGG audiotracks for a moment, so you should convert original soundtracks by yourself, or just download whole TR1-5 music package here: https://opentomb.earvillage.net PLEASE NOTE: Files may need to be renamed for this to work, please see https://github.com/opentomb/OpenTomb/issues/447
Loading screens for TR1-3 and TR5. For TR3, get them from pix directory of your installed official game. Just put this pix directory into
/data/tr3/folder. As for other games, it's a bit tricky to get loading screens, as there were no loading screens for PC versions TR1-2, TR4 used level screenshots as loading screens, and TR5 used an encrypted format to store all loading graphics. So, to ease your life, you can simply download loading screen package here: http://trep.trlevel.de/temp/loading_screens.zip Just put it right into OpenTomb directory, and that should do the trick. Note: the engine supports png and pcx format of screen images.
There is a CMakeLists.txt file provided with source code, so you can compile OpenTomb using CMake. On Windows, you can also compile it from Code::Blocks or Netbeans IDE. Alternatively, you can manually compile it in Code::Blocks or Netbeans by recursively adding all source files from /src directory, and adding these libraries in Linker Settings under Project Build options:
On Linux, just download the source code and run in terminal:
cmake . && make
The required dependencies are the development headers for SDL2, png, ZLIB. You can install them in an Ubuntu-based distro with this command:
sudo apt-get install libopenal-dev libsdl2-dev libpng12-dev libglu1-mesa-dev zlib1g-dev
On Mac, use XCode project, which is also available in source code.
NB: Please note that OpenTomb requires C++11 (
-std=c++11) flag to compile
properly! You may use CPU-specific optimization flags (
-march=core2), as well as general optimization flags (
-O3 flag on old GCC versions may prevent to engine crash as Bullet tends to crash with this optimization level
(GCC 5.1+ may compile it without errors).
Running and Configuration
To run OpenTomb, simply run the executable generated by the build. By default, no command line options are needed. Access the console by pressing `. This allows you to enter commands to select levels, change settings, and more. Enter 'help' to get a list of commands. Enter 'exit' to quit the engine.
Currently, all settings in OpenTomb are managed through config.lua and autoexec.lua. Config.lua contains persistent engine and game settings, while autoexec.lua contains any commands which should be executed on engine start-up.
Config.lua is divided into different sections: screen, audio, render, controls, console and system. In each of these sections, you can change numerous parameters, the names of which are usually fairly intuitive.
Autoexec.lua is a simple list of commands which are ran at startup. Modifying existing commands may cause the engine to function incorrectly.
To select a level, enter 'setgamef(game, level) into either autoexec.lua or in
the console, where game is 1-5. Mansion levels are generally 0, and games which
do not have a mansion begin from level 1. For example, to load level 2 of TR3,
you would enter
OpenTomb is an open-source engine distributed under LGPLv3 license, which means that ANY part of the source code must be open-source as well. Hence, all used libraries and bundled resources must be open-source with GPL-compatible licenses. Here is the list of used libraries and resources and their licenses:
OpenGL — does not need licensing (https://www.opengl.org/about/#11)
OpenAL Soft — LGPL
SDL / SDL Image — zlib
Bullet — zlib
Freetype2 — GPL
Lua — MIT
ffmpeg rpl format and codecs (http://git.videolan.org/)
Droid Sans Mono, Roboto Condensed Regular and Roboto Regular fonts — Apache
NB: Please note that authors and contributors list is constantly extending, as there is more and more people involved in project development, so someone may be missing from this list!
- TeslaRus: main developer.
- Cochrane: renderer rewrites and optimizing, Mac OS X support.
- Gh0stBlade: renderer add-ons, shader port, gameflow implementation, state control fix-ups, camera and AI programming.
- Lwmte: state and scripting fix-ups, controls, GUI and audio modules, trigger and entity system rewrites.
- Nickotte: interface programming, ring inventory implementation, camera fix-ups.
- pmatulka: Linux port and testing.
- richardba: Github migration, Github repo maintenance, website design.
- Saracen: room and static mesh lighting.
- Stohrendorf: code review, original game logic information, auto build system.
- T4Larson: general stability patches and bugfixing.
- vobject: nightly builds, maintaining general compiler compatibility.
- vvs-: testing, feedback, bug report.
- xproger: documentation updates.
- Banderi: documentation, bugfixing.
- gabrielmtzcarrillo: entity shader work.
- filfreire: documentation.
Additional contributions from: Ado Croft (extensive testing), E. Popov (TRN caustics shader port), godmodder (general help), jack9267 (vt loader optimization), meta2tr (testing and bugtracking), shabtronic (renderer fix-ups), Tonttu (console patch) and xythobuz (additional Mac compatibility patches).