- Cloning & initializing submodules
- Build configuration
- Pre-requisites and dependencies
- Linux builds
- Raspberry Pi builds
- Docker builds
- OS X builds
- Windows builds
- Webassembly (Emscripten) builds
RigelEngine uses Git submodules, which means you need to either use git clone --recursive
,
or run one additional command after cloning to initialize submodules:
git clone [email protected]:lethal-guitar/RigelEngine.git
cd RigelEngine
git submodule update --init --recursive
There are a few build options that can be configured when invoking CMake. You don't need to worry about most of these if you just want to build RigelEngine in order to use it. If you plan to work on RigelEngine, read on.
Each option can be either ON
or OFF
. The default is OFF
for all options.
USE_GL_ES
: Build against the OpenGL ES 2.0 API instead of OpenGL 3.0. See OpenGL ES version for more info.WARNINGS_AS_ERRORS
: Make compiler warnings fail the buildBUILD_TESTS
: Build the unit tests (tests
target)BUILD_BENCHMARKS
: Build the benchmarks (benchmarks
target)
For developing RigelEngine, I recommend enabling warnings as errors and tests:
cmake . -DWARNINGS_AS_ERRORS=ON -DBUILD_TESTS=ON
This is how the project is built on CI.
If you wish to run tests with AddressSanitizer (available on clang and gcc), use CMAKE_BUILD_TYPE=Asan
, like so:
cmake . -DCMAKE_BUILD_TYPE=Asan -DWARNINGS_AS_ERRORS=ON -DBUILD_TESTS=ON
ctest -T MemCheck # add other ctest options here, -V is a good one
To build from source, a C++ 17 compatible compiler is required. The project has been built successfully on the following compilers:
- Microsoft Visual Studio 2019 (version 16.1.6 or newer)
- gcc 8.1.0
- clang 7.0.0
Slightly older versions of gcc/clang might also work, but I haven't tried that.
CMake version 3.13 or newer is required in order to generate build files.
The project depends on the following libraries, which CMake needs to be able to find for the build to work:
- SDL >= 2.0.4
- SDL_mixer >= 2.0.1
All other dependencies are already provided as submodules, source
code (in the 3rd_party
directory) or fetched on configuration, and will be built along with RigelEngine.
In other words, you don't need to worry about providing these dependencies.
These are:
- Catch testing framework
- DBOPL AdLib emulator (taken from DosBox)
- Dear ImGui UI framework
- entityx Entity-Component-System framework
- File browser extension for Dear ImGui
- Glad OpenGL function loader generator
- GLM math library
- JSON for modern C++
- Lyra command line parser
- Speex Resampler (taken from libspeex)
- STB image image reading/writing library
- STB rect_pack rectangle packer for building texture atlases
Enabling BUILD_BENCHMARKS
will automatically fetch googlebenchmark. You can then build the benchmarks
target (this will also build googlebenchmark). Make sure you build in Release
and disable CPU scaling (see: link for more details).
In order to be able to install all required dependencies from the system's package manager, a fairly recent distro is required. I have successfully built the project using the following instructions on Ubuntu 19.04 and 19.10. Building on Ubuntu 18.04 is also possible, but it requires a few more steps.
For other distros (not based on Debian), the same instructions should work as well, with only the package installation command needing adaptation, as long as all necessary dependencies are available at recent enough versions.
# Install all external dependencies, as well as the CMake build system:
sudo apt-get install cmake libsdl2-dev libsdl2-mixer-dev
# Configure and build (run inside your clone of the repo):
mkdir build
cd build
cmake ..
make -j$(nproc)
# If you plan to develop RigelEngine, I recommend adding
# -DWARNINGS_AS_ERRORS=ON -DBUILD_TESTS=ON to the cmake command.
# Now run it!
./src/RigelEngine
Ubuntu 18.04 almost provides everything we need out of the box, aside from CMake and gcc. Fortunately, we can install gcc 8 alongside the system default of gcc 7, and it's available in the package manager. CMake, however, has to be built from source or installed via a PPA.
# Install all external dependencies, and gcc 8. CMake will be built from source.
sudo apt-get install g++-8 libsdl2-dev libsdl2-mixer-dev
# Now we need to install a newer version of CMake. If you already have CMake
# installed, you can uninstall it by running:
#
# sudo apt purge --auto-remove cmake
#
# If not, proceed directly with the following:
mkdir ~/temp
cd ~/temp
wget https://github.com/Kitware/CMake/releases/download/v3.15.4/cmake-3.15.4.tar.gz
tar -xzvf cmake-3.15.4.tar.gz
cd cmake-3.15.4
./bootstrap
make -j$(nproc)
sudo make install
# Now, when you run cmake --version, it should say 3.15. You can delete the
# ~/temp folder.
# Now we can build. Navigate to where you've cloned the repo, then:
mkdir build
cd build
# Now we need to tell CMake to use gcc 8 instead of the system default
# (which is 7). You only need to do this when running CMake for the first time.
export CC=`which gcc-8`
export CXX=`which g++-8`
# Finally, we can configure and build as usual (see above).
cmake ..
make -j$(nproc)
# Now run it!
./src/RigelEngine
On Fedora, the following command installs all required and optional dependencies:
sudo dnf install cmake SDL2-devel SDL2_mixer-devel
This assumes that make
, gcc
and gcc-c++
are already installed.
On Linux, RigelEngine can be built in two versions: Regular and OpenGL ES. The latter is useful for system with an older graphics card (e.g. Intel integrated GPU) which doesn't support OpenGL 3.0.
To build the GL ES version, pass -DUSE_GL_ES=ON
when running CMake, then build as usual:
mkdir build
cd build
cmake .. -DUSE_GL_ES=ON
make -j$(nproc)
If you've already built the regular version before, you can reuse the existing build dir
(skip the mkdir
step) but otherwise run the same commands.
❗ Make sure to read Running on Raspberry Pi for information on how to achieve best performance!
If you're using RetroPie, you can use this build script made by @Exarkuniv. Otherwise, read on!
To build on the Pi itself, I recommend at least Raspbian (aka Raspberry Pi OS) Buster. Older versions like Stretch don't have recent enough versions of CMake and gcc.
Installing the dependencies works exactly like on Ubuntu.
When building, you need to enable OpenGL ES Support:
mkdir build
cd build
cmake .. -DUSE_GL_ES=ON
make # single-job is better for RPI
The provided docker image allows you to mimic one of the CI environments (ubuntu:latest).
Build the image using
docker build . -f docker/ubuntu.Dockerfile -t rigel-build
Then run your container with:
# build it, debug it, etc..
docker run -ti --cap-add=SYS_PTRACE --security-opt seccomp=unconfined -v $(pwd):/workdir -w /workdir rigel-build
And now follow the build steps from Ubuntu.
You can also run the game from the container by following these instructions:
- on your host:
xhost +
(will allow connections from anything - you can be more granular if you wish) - run the same build container with:
# ability to run the game with the GPU mapped + X forwarding
docker run -ti --device=/dev/dri:/dev/dri --cap-add=SYS_PTRACE --security-opt seccomp=unconfined -e DISPLAY=$DISPLAY -v /tmp/.X11-unix:/tmp/.X11-unix --net=host -v $(pwd):/workdir -w /workdir rigel-build
- build & run, same as you would on your local machine
❗ On Mojave (10.14), non-Apple clang must be installed via Homebrew, Apple's clang does not have all required C++ library features. Starting with Catalina (10.15), Xcode's clang works fine.
# Install dependencies
# You might need to run brew update.
brew install cmake sdl2 sdl2_mixer
# Configure & build
mkdir build
cd build
cmake ..
make -j$(nproc)
# Now run it!
./src/RigelEngine.app/Contents/MacOS/RigelEngine
❗ Note that you'll need Xcode 10.
# You might need to run brew update.
brew install llvm@8 cmake sdl2 sdl2_mixer
# Set up environment variables so that CMake picks up the newly installed clang -
# this is only necessary the first time.
export rigel_llvm_path=`brew --prefix llvm@8`;
export CC="$rigel_llvm_path/bin/clang";
export CXX="$CC++";
export CPPFLAGS="-I$rigel_llvm_path/include";
export LDFLAGS="-L$rigel_llvm_path/lib -Wl,-rpath,$rigel_llvm_path/lib";
unset rigel_llvm_path;
# Now, the regular build via CMake should work:
mkdir build
cd build
cmake
make -j$(nproc)
# Now run it!
./src/RigelEngine.app/Contents/MacOS/RigelEngine
❗ For best performance, make sure to switch to "Release" mode in Visual Studio before building.
First, you need to install CMake if you don't have it already.
You can grab it from the Kitware website, I went
for the Windows win64-x64 Installer
variant.
For getting the dependencies, I strongly recommend using
vcpkg.
You then need to pass CMAKE_TOOLCHAIN_FILE=C:/path/to/your/vcpkgdir/scripts/buildystems/vcpkg.cmake
when invoking CMake.
❗ Make sure to specify the toolchain file as absolute path. If the toolchain file path is incorrect, CMake will just silently ignore it, resulting in "package not found" errors. So in case of errors, I'd recommend double checking the path first.
# Install dependencies
vcpkg install sdl2:x64-windows sdl2-mixer:x64-windows --triplet x64-windows
# Run CMake
mkdir build
cd build
# Remember to replace <vcpkg_root> with the path to where you installed vcpkg!
cmake .. -DCMAKE_TOOLCHAIN_FILE=<vckpkg_root>/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x64-windows -DCMAKE_GENERATOR_PLATFORM=x64
# This will open the generated Visual Studio solution
start RigelEngine.sln
❗ Currently, only 64-bit builds are regularly tested and built on CI. Building for 32-bit is possible, but there might be small build errors from time to time. If you'd like to build for 32-bit and have trouble sorting out build errors, feel free to open an issue and I'll look into it.
# Install dependencies
vcpkg install sdl2:x86-windows sdl2-mixer:x86-windows --triplet x86-windows
# Run CMake
mkdir build
cd build
# Remember to replace <vcpkg_root> with the path to where you installed vcpkg!
cmake .. -DCMAKE_TOOLCHAIN_FILE=<vckpkg_root>/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x86-windows -DCMAKE_GENERATOR_PLATFORM=Win32
# This will open the generated Visual Studio solution
start RigelEngine.sln
Rigel Engine can be built to run on a web browser using Emscripten. Note that this is still work in progress, as there are some issues to resolve.
Refer to Emscripten's README for instructions on how to install and activate Emscripten.
You can verify the installation by running the emcc
command. If it executes without errors then everything is configured correctly.
The instructions to build are the same as above, except for the CMake part:
emcmake cmake .. -DWEBASSEMBLY_GAME_PATH=<path-to-duke2-folder>
make -j$(nproc)
This will produce a couple of files in the <path-to-cmake-build-dir>/src
folder.
To run the game, you need to run a web server to host the files in that folder,
and then open RigelEngine.html
in your browser.
Just opening RigelEngine.html
directly will not work, as the web page needs to load the wasm code and data, which most browsers don't allow when using the local file:///
protocol.
The easiest way to host the files is using Python. In the CMake build directory, run:
# Python 2
python -m SimpleHTTPServer
# Python 3
python3 -m http.server
This will host the game at localhost:8000/src/RigelEngine.html
.