Cemu/BUILD.md

# Build instructions

## Windows

Prerequisites:
- A recent version of Visual Studio 2022 (recommended but not required) with the following additional components:
  - C++ CMake tools for Windows
  - Windows 10/11 SDK
- git

Instructions:

1. Run `git clone --recursive https://github.com/cemu-project/Cemu`
2. Launch `Cemu/generate_vs_solution.bat`.
    - If you installed VS to a custom location or use VS 2019, you may need to manually change the path inside the .bat file
3. Wait until it's done, then open `Cemu/build/Cemu.sln` in Visual Studio
4. Then build the solution and once finished you can run and debug it, or build it and check the /bin folder for the final Cemu.exe.

You can also skip steps 3-5 and open the root folder of the cloned repo directly in Visual Studio (as a folder) and use the built-in cmake support but be warned that cmake support in VS can be a bit finicky.

## Linux

To compile Cemu, a recent enough compiler and STL with C++20 support is required! clang-12 or higher is what we recommend.

### Installing dependencies

#### For Ubuntu and derivatives:
`sudo apt install -y git cmake ninja-build nasm libgtk-3-dev libsecret-1-dev libgcrypt20-dev libsystemd-dev freeglut3-dev libpulse-dev`  
Additionally, for ubuntu 20.04 only:
 - `sudo apt install -y clang-12`
 - At step 3 while building, use  
   `cmake -S . -B build -DCMAKE_BUILD_TYPE=release -DCMAKE_C_COMPILER=/usr/bin/clang-12 -DCMAKE_CXX_COMPILER=/usr/bin/clang++-12 -G Ninja -DCMAKE_MAKE_PROGRAM=/usr/bin/ninja`

#### For Arch and derivatives:
`sudo pacman -S git cmake clang ninja nasm base-devel linux-headers gtk3 libsecret libgcrypt systemd freeglut zip libpulse`

#### For Fedora and derivatives:
`sudo dnf install git cmake clang ninja-build nasm kernel-headers gtk3-devel libsecret-devel libgcrypt-devel systemd-devel freeglut-devel perl-core zlib-devel cubeb-devel`

### Build Cemu using cmake and clang
1. `git clone --recursive https://github.com/cemu-project/Cemu`
2. `cd Cemu`
3. `cmake -S . -B build -DCMAKE_BUILD_TYPE=release -DCMAKE_C_COMPILER=/usr/bin/clang -DCMAKE_CXX_COMPILER=/usr/bin/clang++ -G Ninja`
4. `cmake --build build`
5. You should now have a Cemu executable file in the /bin folder, which you can run using `./bin/Cemu`.

#### Using GCC
While we use and test Cemu using clang, using GCC might work better with your distro (they should be fairly similar performance/issues wise and should only be considered if compilation is the issue).  
You can use it by replacing the step 3 with the following:
`cmake -S . -B build -DCMAKE_BUILD_TYPE=release -DCMAKE_C_COMPILER=/usr/bin/gcc -DCMAKE_CXX_COMPILER=/usr/bin/g++ -G Ninja`

#### Troubleshooting steps
 - If step 3 gives you an error about not being able to find ninja, try appending `-DCMAKE_MAKE_PROGRAM=/usr/bin/ninja` to the command and running it again.
 - If step 3 fails while compiling the boost-build dependency, it means you don't have a working/good standard library installation. Check the integrity of your system headers and making sure that C++ related packages are installed and intact.
 - If step 3 gives a random error, read the `[package-name-and-platform]-out.log` and `[package-name-and-platform]-err.log` for the actual reason to see if you might be lacking the headers from a dependency.
 - If step 3 is still failing or if you're not able to find the cause, please make an issue on our Github about it!
 - If step 4 gives you an error that contains something like `main.cpp.o: in function 'std::__cxx11::basic_string...`, you likely are experiencing a clang-14 issue. This can only be fixed by either lowering the clang version or using GCC, see below.
 - If step 4 gives you a different error, you could report it to this repo or try using GCC. Just make sure your standard library and compilers are updated since Cemu uses a lot of modern features!
- If step 4 gives you undefined libdecor_xx, you are likely experiencing an issue with sdl2 package that comes with vcpkg. Delete sdl2 from vcpkg.json in source file and recompile