magnum/doc/building.dox

/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018
              Vladimír Vondruš <mosra@centrum.cz>

    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the "Software"),
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    the rights to use, copy, modify, merge, publish, distribute, sublicense,
    and/or sell copies of the Software, and to permit persons to whom the
    Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included
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    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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*/

namespace Magnum {

/** @page building Downloading and building
@brief Guide how to download and build Magnum on different platforms.

@m_keywords{Building}
@m_keyword{ANGLE OpenGL compatibility layer,,}

@tableofcontents
@m_footernavigation

@section building-packages Prepared packages

The easiest way to install Magnum is to use one of the ready-made packages for
your platform of choice. See @ref building-manual if you want to have more
control and @ref building-cross for cross-compiling to other platforms.

-   @ref building-packages-vcpkg
-   @ref building-packages-arch
-   @ref building-packages-deb
-   @ref building-packages-gentoo
-   @ref building-packages-brew

The engine itself is kept as small as possible with only minimal dependencies.
In order to use extra functionality, often depending on external libraries, you
need to build also packages of additional repositories. Various importer
plugins for image, audio and 3D model formats are maintained in the
@ref building-plugins "Plugins repository", integration with external math and
physics libraries is provided by @ref building-integration "Integration libraries"
and other extra features are in the @ref building-extras "Extra libraries".
Various examples are provided by the @ref building-examples "Example repository".

@subsection building-packages-vcpkg Vcpkg packages on Windows

Magnum is available as a [Vcpkg](https://github.com/Microsoft/vcpkg) package.
After setting up Vcpkg like described in the README, you can install latest
stable version of Magnum with all its dependencies like this:

@code{.bat}
vcpkg install magnum
@endcode

But often you may want to install the latest Git revision of all Magnum
projects instead:

@code{.bat}
vcpkg install corrade --head
vcpkg install magnum --head
@endcode

This by default installs a 32-bit dynamic version of the package, you can use
@cb{.bat} vcpkg install magnum:x64-windows @ce or
@cb{.bat} vcpkg install magnum:x64-windows-static @ce to install a 64-bit
(static) version instead. You can also use the `VCPKG_DEFAULT_TRIPLET` variable
to change the default --- see the
<a href="https://github.com/Microsoft/vcpkg/blob/master/docs/users/triplets.md">Vcpkg triplet documentation</a>
for more information.

Not all features are installed by default, only those that are implicitly
enabled in @ref building-features together with @ref Platform::Sdl2Application "Sdl2Application".
To opt-in or opt-out of additional features, you can use the following syntax;
feature names are simply names of CMake `WITH_*` options but lowercase. See the
<a href="https://github.com/Microsoft/vcpkg/blob/master/docs/specifications/feature-packages.md">feature documentation</a>
for more information.

@code{.bat}
vcpkg install magnum[glfwapplication,tgaimporter]
@endcode

Packages installed using Vcpkg can be used straight away in Visual Studio ---
all you need to do is to @cpp #include @ce the headers you want, the
buildsystem will do all needed library linking and setup behind the scenes
automatically. <em>(Cool, isn't it?)</em>

@note If Visual Studio doesn't find the packages, check its verbose output, it
    might point to a mismatch of the triplet above or broken Vcpkg integration.

In order to make Magnum projects installed using Vcpkg available to CMake-based
projects, specify the Vcpkg toolchain file on the command line when invoking
CMake in a fresh build directory, for example:

@code{.bat}
mkdir build && cd build
cmake .. -DCMAKE_TOOLCHAIN_FILE=C:/src/vcpkg/scripts/buildsystems/vcpkg.cmake
@endcode

If you want to pass additional flags to CMake, run @cb{.bat} vcpkg edit magnum @ce
and edit `OPTIONS` in @cmake vcpkg_configure_cmake() @ce.

There is also a Vcpkg package for @ref building-plugins-packages-vcpkg "Magnum Plugins",
@ref building-integration-packages-vcpkg "Magnum Integration" and
@ref building-extras-packages-vcpkg "Magnum Extras".

@subsection building-packages-arch ArchLinux packages

Package for the latest stable release is maintained in the `community` repo.
Installing is as simple as this:

@code{.sh}
sudo pacman -S magnum
@endcode

In `package/archlinux/magnum-git` there is a package for Git development build.
The package is also in AUR as
[magnum-git](https://aur.archlinux.org/packages/magnum-git/). It depends on the
@ref building-corrade-packages-arch "Corrade ArchLinux package".

There are also quite a few development packages for native builds, OpenGL ES
builds, cross-compilation for Emscripten, Android and MinGW or various
sanitizer/coverage builds. See the PKGBUILD files in the `package/archlinux`
directory. They allow you to build and install the package directly from the
source tree. Example usage:

@code{.sh}
git clone git://github.com/mosra/magnum && cd magnum
cd package/archlinux
makepkg -fp PKGBUILD # or any other PKGBUILD file
@endcode

In most cases the development PKGBUILDs also contain a @cb{.sh} check() @ce
function which will run all unit tests before packaging. That might sometimes
fail or take too long, pass `--nocheck` to `makepkg` to skip that.

Once built, install the package using `pacman`:

@code{.sh}
sudo pacman -U magnum-*.pkg.tar.xz
@endcode

Edit the PKGBUILDs if you want to pass additional flags to CMake or
@ref building-features "enable / disable additional features".

There are also ArchLinux packages for @ref building-plugins-packages-arch "Magnum Plugins", @ref building-integration-packages-arch "Magnum Integration",
@ref building-extras-packages-arch "Magnum Extras" and
@ref building-examples-packages-arch "Magnum Examples".

@subsection building-packages-deb Packages for Debian, Ubuntu and derivatives

Prebuilt packages of the latest stable version for Ubuntu 14.04, 16.04 and
18.04 are available through a PPA. To install packages related to Magnum and
Corrade, you can add the repository and then install the packages with the
following commands:

@code{.sh}
sudo add-apt-repository ppa:chrome/magnum.graphics
sudo apt-get update
sudo apt-get install magnum magnum-dev
@endcode

For more information about these packages, please visit
[the PPA page](https://launchpad.net/~chrome/+archive/ubuntu/magnum.graphics).

To build your own package, the `package/debian/` directory contains all files
needed for building Debian packages. You need the
@ref building-corrade-packages-deb "Corrade Debian package" installed and in
addition also the `dpkg-dev` and `debhelper` packages. Building is easy, just
change directory to package root, link or copy `package/debian` directory there
and run `dpkg-buildpackage`:

@code{.sh}
git clone git://github.com/mosra/magnum && cd magnum
ln -s package/debian .
dpkg-buildpackage
@endcode

This will compile binary and development packages, which will then appear in a
parent directory. Install them using `dpkg`:

@code{.sh}
sudo dpkg -i ../magnum*.deb
@endcode

If you want to pass additional flags to CMake or
@ref building-features "enable / disable additional features", add them to
`dh_auto_configure` at the bottom of `debian/rules`. Watch out, as
indentation has to be done using tabs, not spaces.

There are also Debian packages for @ref building-plugins-packages-deb "Magnum Plugins", @ref building-integration-packages-deb "Magnum Integration",
@ref building-extras-packages-deb "Magnum Extras" and
@ref building-examples-packages-deb "Magnum Examples".

@subsection building-packages-gentoo Gentoo Linux ebuilds

Gentoo Git ebuild is available in the `package/gentoo` directory. Get the
@ref building-corrade-packages-gentoo "Corrade Gentoo package" first and then
build and install Magnum like this:

@code{.sh}
git clone git://github.com/mosra/magnum && cd magnum
cd package/gentoo
sudo ebuild dev-libs/magnum/magnum-99999.ebuild manifest clean merge
@endcode

If you want to pass additional flags to CMake or
@ref building-features "enable / disable additional features", add them to
`mycmakeargs` in the `*.ebuild` file.

There are also Gentoo packages for @ref building-plugins-packages-gentoo "Magnum Plugins", @ref building-integration-packages-gentoo "Magnum Integration",
@ref building-extras-packages-gentoo "Magnum Extras" and
@ref building-examples-packages-gentoo "Magnum Examples".

@subsection building-packages-brew Homebrew formulas for macOS

macOS [Homebrew](https://brew.sh) formulas building the latest Git revision are
in the `package/homebrew` directory. Either use the `*.rb` files directly or
use the tap at https://github.com/mosra/homebrew-magnum. This will install the
latest stable version of Magnum with all its dependencies:

@code{.sh}
brew install mosra/magnum/magnum
@endcode

But often you may want to install the latest Git revision of all Magnum
projects instead:

@code{.sh}
brew install --HEAD mosra/magnum/corrade
brew install --HEAD mosra/magnum/magnum
@endcode

When installing from the `*.rb` files you need to install the
@ref building-corrade-packages-brew "Corrade Homebrew package" first. If you
want to pass additional flags to CMake or
@ref building-features "enable / disable additional features", edit the `*.rb`
file.

There are also Homebrew packages for @ref building-plugins-packages-brew "Magnum Plugins", @ref building-integration-packages-brew "Magnum Integration",
@ref building-extras-packages-brew "Magnum Extras" and
@ref building-examples-packages-brew "Magnum Examples".

@section building-manual Manual build

Minimal set of tools and libraries required for building is:

-   C++ compiler with good C++11 support. Compilers which are tested to have
    everything needed are **GCC** >= 4.7, **Clang** >= 3.1 and **MSVC** >= 2015.
    On Windows you can also use **MinGW-w64**.
-   **CMake** >= 2.8.12
-   **Corrade** --- Plugin management and utility library. See
    @ref building-corrade "Corrade download and installation guide" for more
    information.

Additional functionality is provided separately in
@ref building-plugins "Magnum Plugins",
@ref building-integration "Magnum Integration",
@ref building-extras "Magnum Extras" and
@ref building-examples "Magnum Examples".

@subsection building-download Downloading the sources

The source is available on GitHub: https://github.com/mosra/magnum. Clone the
repository with your favorite IDE or Git GUI, download currrent snapshot as a
compressed archive or use the command line:

@code{.sh}
git clone git://github.com/mosra/magnum.git
@endcode

Relevant information about CMake usage was described in
@ref building-corrade-cmake "Corrade download and installation guide", this
guide is assuming you have at least basic knowledge of CMake.

@subsection building-linux Via command-line (on Linux/Unix)

On Unix-based OSes, the library (for example with support for SDL2
applications) can be built and installed using these four commands:

@code{.sh}
mkdir build && cd build
cmake .. \
    -DCMAKE_INSTALL_PREFIX=/usr \
    -DWITH_SDL2APPLICATION=ON
make
make install # sudo may be needed
@endcode

See @ref building-features "below" for additional configuration options.

If you have the dependencies installed in non-standard location (other than
`/usr`, e.g. `/home/xyz/projects`), set `CMAKE_PREFIX_PATH` to that directory
to help CMake find them. You can enter more different dirs if you separate them
with semicolons.

Also, if you plan to install the library to non-standard location, you might
want to set `CMAKE_INSTALL_RPATH` to `lib/` subdir of given prefix (e.g.
`/home/xyz/projects/lib`), so the dynamic libraries can be found at runtime.

@subsection building-windows Building on Windows

On Windows you can use either MSVC or the MinGW-w64 compiler. It's then up to
you whether you will use QtCreator, Visual Studio or anoother IDE or do the
build from a command line. Note that for most convenient usage it's best use
some dedicated directory (e.g. `C:/Sys`) for installing dependencies instead of
putting each dependency to its own directory in `C:/Program Files` or
elsewhere. Then you can just add its `bin/` subdir (e.g. `C:/Sys/bin`) to
@cb{.bat} %PATH% @ce so all the DLLs are found when running the executables. If
you are using MinGW-w64, the `C:/MinGW` directory is in most cases already
prepared for exactly this.

Then, when running CMake, set `CMAKE_PREFIX_PATH` and `CMAKE_INSTALL_PREFIX`
value to that directory (e.g. `-DCMAKE_INSTALL_PREFIX=C:/Sys`).

@subsubsection building-windows-msvc Using Visual Studio

On Windows CMake by default creates Visual Studio project files.

The most straightforward way to build and install the library is again via the
command line. The bonus point is that you don't even need to wait for Visual
Studio to load:

@code{.bat}
mkdir build && cd build
cmake -DCMAKE_INSTALL_PREFIX="C:/Sys" ..
cmake --build .
cmake --build . --target install
@endcode

If you want to build and install from Visual Studio, just open the `Magnum.sln`
project file generated by CMake in the build directory.

@subsubsection building-windows-qtcreator Using QtCreator

On Windows, besides other IDEs, you can also use QtCreator (just QtCreator, you
don't need the full Qt SDK). Configure it to use CMake and either the MSVC
compiler or MinGW-w64 and then just open project's root `CMakeLists.txt` file
within it. QtCreator then asks you where to create build directory, allows you
to specify initial CMake parameters (e.g. `CMAKE_PREFIX_PATH` and
`CMAKE_INSTALL_PREFIX`) and then you can just press *Configure* and everything
is ready to be built.

After the initial import you might want to reconfigure some CMake variables,
see @ref building-features "below" for more information.

Installation to given prefix can be done from within QtCreator by adding a new
`make install` build rule.

@subsection building-features Enabling or disabling features

The libraries are build as shared by default. If you are developing for a
platform which doesn't support shared libraries or if you just want to link
them statically, enable `BUILD_STATIC` to build the libraries as static.
Building of static plugins is controlled with a separate `BUILD_PLUGINS_STATIC`
variable. If you plan to use the static libraries and plugins with shared
libraries later, enable also position-independent code with `BUILD_STATIC_PIC`.
If you want to build with another compiler (e.g. Clang), pass
`-DCMAKE_CXX_COMPILER=clang++` to CMake.

Libraries and static plugins built in `Debug` configuration (e.g. with
`CMAKE_BUILD_TYPE` set to `Debug`) have a `-d` suffix to make it possible to
have both debug and release libraries installed alongside each other. *Dynamic*
plugins in `Debug` configuration are installed to `magnum-d` subdirectory
instead of `magnum`. Headers and other files are the same for both debug and
release configurations. The library and plugin distinction is handled
semi-automatically when using Magnum in depending projects, see @ref cmake for
more information.

Particular platforms have additional requirements when it comes to location of
installed files. The following variables are supported:

-   `LIB_SUFFIX` --- Setting this variable to `64` can be used to tell CMake to
    install to `lib64/` instead of `lib/`. In most cases this variable is
    autodetected, so you don't need to set it yourself.
-   `MAGNUM_DEPLOY_PREFIX` --- Used on @ref CORRADE_TARGET_EMSCRIPTEN "Emscripten"
    to override location where web demos and utilities (such as @ref magnum-gl-info)
    are installed, so you can have libraries installed to a system location and
    utilities to your webserver, for example. Defaults to ``.``. If a relative
    path is used, it's relative to `CMAKE_INSTALL_PREFIX`.
-   `MAGNUM_INCLUDE_INSTALL_PREFIX` --- Used on @ref CORRADE_TARGET_ANDROID "Android"
    to override location where platform-independent include files, CMake
    scripts and other files are installed. CMake on Android by default searches
    for binaries in <tt>&lt;ndk&gt;/platforms/android-&lt;api&gt;/arch-&lt;arch&gt;/usr</tt>
    based on target API and platform, but looks for headers in a central
    location at <tt>&lt;ndk&gt;/sysroot/usr</tt>. Defaults to ``.``. If a
    relative path is used, it's relative to `CMAKE_INSTALL_PREFIX`.

The library is constantly evolving and thus some APIs are deprecated and then
later removed in favor of better ones. To preserve backwards compatibility,
Magnum is by default built with all deprecated APIs included. However, to make
your code more robust and future-proof, it's recommended to build the library
with `BUILD_DEPRECATED` disabled.

By default the engine is built for desktop OpenGL. Using the `TARGET_*` CMake
options you can target other platforms. Note that some features are
available for desktop OpenGL only, see @ref requires-gl.

-   `TARGET_GL` --- Build libraries with OpenGL interoperability enabled.
    Enabled by default when `WITH_GL` is enabled. Disabling this will cause
    other libraries to not depend on the @ref GL library, but doesn't affect
    the @ref GL library itself.
-   `TARGET_GLES` --- Target OpenGL ES. Available only when `WITH_GL` is
    enabled.
-   `TARGET_GLES2` --- Target OpenGL ES 2.0 instead of 3.0 and later. Available
    only when `WITH_GL` is set. Currently enabled by default when `TARGET_GLES`
    is set.
-   `TARGET_DESKTOP_GLES` --- Target OpenGL ES on desktop, i.e. use OpenGL ES
    emulation in desktop OpenGL drivers. Available on Linux and Windows, though
    might not be supported by all drivers. Available only when `WITH_GL` is
    enabled.
-   `TARGET_HEADLESS` --- Build command-line utilities for use on a headless
    machine. Basically it means that EGL with no display attachment is being
    used everywhere instead of platform-specific toolkits like CGL, GLX or WGL.
    Supported mainly on OpenGL ES drivers. Available only when `WITH_GL` is
    enabled.
-   `TARGET_VK` --- Build libraries with Vulkan interoperability enabled.
    Enabled by default when `WITH_VK` is enabled. Disabling this will cause
    libraries to not depend on the @ref Vk library, but  doesn't affect the
    @ref Vk library itself.

By default the engine is built in a way that allows having multiple independent
thread-local Magnum contents. This might cause some performance penalties ---
if you are sure that you will never need such feature, you can disable it via
the `BUILD_MULTITHREADED` option.

The features used can be conveniently detected in depending projects both in
CMake and C++ sources, see @ref cmake and @ref Magnum/Magnum.h for more
information. See also @ref corrade-cmake and @ref Corrade/Corrade.h for
related info for the Corrade library.

By default the engine is built with nearly everything except the @ref Audio
library, plugins, command-line utilities and application libraries (see below).
Using the following `WITH_*` CMake options you can specify which parts will
be built and which not:

-   `WITH_AUDIO` --- Build the @ref Audio library. Depends on
    [OpenAL](https://www.openal.org/), not built by default.
-   `WITH_DEBUGTOOLS` --- Build the @ref DebugTools library.
-   `WITH_GL` --- Build the @ref GL library. Enabled automatically if
    `WITH_SHADERS` or `WITH_TEXT` is enabled.
-   `WITH_MESHTOOLS` --- Build the @ref MeshTools library. Enables also
    building of the Trade library.
-   `WITH_PRIMITIVES` --- Build the @ref Primitives library. Enables also
    building of the Trade library.
-   `WITH_SCENEGRAPH` --- Build the @ref SceneGraph library. Enabled
    automatically if `WITH_SHAPES` is enabled.
-   `WITH_SHADERS` --- Build the @ref Shaders library. Enables also building of
    the GL library.
-   `WITH_SHAPES` --- Build the @ref Shapes library. Enables also building of
    the SceneGraph library.
-   `WITH_TEXT` --- Build the @ref Text library. Enables also building of
    the TextureTools and GL libraries.
-   `WITH_TEXTURETOOLS` --- Build the @ref TextureTools library. Enabled
    automatically if `WITH_TEXT` or `WITH_DISTANCEFIELDCONVERTER` is enabled.
-   `WITH_TRADE` --- Build the @ref Trade library.
-   `WITH_VK` --- Build the @ref Vk library

There are more involved component dependencies that are not described here (for
example the @ref DebugTools has some functionality that gets built only when
@ref SceneGraph is enabled, which then makes it dependent on @ref Shaders and
other things), but the CMake buildsystem takes care of these and only the
relevant toggleable options are shown in CMake GUI or `ccmake`.

None of the @ref Platform "application libraries" is built by default (and you
need at least one, unless you are handling platform integration yourself ---
see @ref platform-custom for more information). As they are rather tiny, they
are always built as static. Choose the one that suits your requirements and
your platform best:

-   `WITH_ANDROIDAPPLICATION` --- Build the
    @ref Platform::AndroidApplication "AndroidApplication" library. Available
    only on @ref CORRADE_TARGET_ANDROID "Android". Enables also building of the
    GL library.
-   `WITH_GLFWAPPLICATION` --- Build the
    @ref Platform::GlfwApplication "GlfwApplication" library. Depends on
    [GLFW](http://glfw.org).
-   `WITH_GLUTAPPLICATION` --- Build the
    @ref Platform::GlutApplication "GlutApplication" library. Depends on
    [GLUT](http://freeglut.sourceforge.net/). Enables also building of the GL
    library.
-   `WITH_GLXAPPLICATION` --- Build the
    @ref Platform::GlxApplication "GlxApplication" library. Depends on **X11**.
    Enables also building of the GL library.
-   `WITH_SDL2APPLICATION` --- Build the
    @ref Platform::Sdl2Application "Sdl2Application" library. Depends on
    [SDL2](http://www.libsdl.org).
-   `WITH_XEGLAPPLICATION` --- Build the
    @ref Platform::XEglApplication "XEglApplication" library. Enables also
    building of the GL library.
-   `WITH_WINDOWLESSCGLAPPLICATION` --- Build the
    @ref Platform::WindowlessCglApplication "WindowlessCglApplication" library.
    Enables also building of the GL library.
-   `WITH_WINDOWLESSEGLAPPLICATION` --- Build the
    @ref Platform::WindowlessEglApplication "WindowlessEglApplication" library.
    Enables also building of the GL library.
-   `WITH_WINDOWLESSGLXAPPLICATION` --- Build the
    @ref Platform::WindowlessGlxApplication "WindowlessGlxApplication" library.
    Enables also building of the GL library.
-   `WITH_WINDOWLESSIOSAPPLICATION` --- Build the
    @ref Platform::WindowlessIosApplication "WindowlessIosApplication" library.
    Enables also building of the GL library.
-   `WITH_WINDOWLESSWGLAPPLICATION` --- Build the
    @ref Platform::WindowlessWglApplication "WindowlessWglApplication" library.
    Enables also building of the GL library.
-   `WITH_WINDOWLESSWINDOWSEGLAPPLICATION` --- Build the
    @ref Platform::WindowlessWindowsEglApplication "WindowlessWindowsEglApplication"
    library. Enables also building of the GL library.

None of the context libraries is built by default. Similarly to the application
libraries, they are always built as static. You need them only if you chose to
not use any of the application libraries above (see @ref platform-custom for
more information):

-   `WITH_CGLCONTEXT` --- Build the CGL context handling library. Enables also
    building of the GL library.
-   `WITH_EGLCONTEXT` --- Build the EGL context handling library. Enables also
    building of the GL library.
-   `WITH_GLXCONTEXT` --- Build the GLX context handling library. Enables also
    building of the GL library.
-   `WITH_WGLCONTEXT` --- Build the WGL context handling library. Enables also
    building of the GL library.

There are also extensions to @ref Corrade::TestSuite::Tester for testing GPU
code:

-   `WITH_OPENGLTESTER` --- The @ref GL::OpenGLTester class. Enables also
    building of the GL library and one of the windowless application libraries
    based on the target platform.

Magnum also contains a set of dependency-less plugins for importing essential
file formats. Additional plugins are provided in a separate plugin repository,
see @ref building-plugins for more information. None of the plugins is built by
default.

-   `WITH_ANYAUDIOIMPORTER` --- Build the @ref Audio::AnyImporter "AnyAudioImporter"
    plugin. Enables also building of the @ref Audio library.
-   `WITH_ANYIMAGECONVERTER` --- Build the
    @ref Trade::AnyImageConverter "AnyImageConverter" plugin. Enables also
    building of the @ref Trade library.
-   `WITH_ANYIMAGEIMPORTER` --- Build the @ref Trade::AnyImageImporter "AnyImageImporter"
    plugin. Enables also building of the @ref Trade library.
-   `WITH_ANYSCENEIMPORTER` --- Build the @ref Trade::AnySceneImporter "AnySceneImporter"
    plugin. Enables also building of the @ref Trade library.
-   `WITH_MAGNUMFONT` --- Build the @ref Text::MagnumFont "MagnumFont" plugin.
    Enables also building of the @ref Text library and the
    @ref Trade::TgaImporter "TgaImporter" plugin.
-   `WITH_MAGNUMFONTCONVERTER` --- Build the
    @ref Text::MagnumFontConverter "MagnumFontConverter" plugin. Enables also
    building of the @ref Text library and the
    @ref Trade::TgaImageConverter "TgaImageConverter" plugin.
-   `WITH_OBJIMPORTER` --- Build the @ref Trade::ObjImporter "ObjImporter"
    plugin. Enables also building of the @ref Trade library.
-   `WITH_TGAIMPORTER` --- Build the @ref Trade::TgaImporter "TgaImporter"
    plugin. Enables also building of the @ref Trade library.
-   `WITH_TGAIMAGECONVERTER` --- Build the
    @ref Trade::TgaImageConverter "TgaImageConverter" plugin. Enables also
    building of the @ref Trade library.
-   `WITH_WAVAUDIOIMPORTER` --- Build the @ref Audio::WavImporter "WavAudioImporter"
    plugin. Enables also building of the @ref Audio library.

There are also a few command-line utilities, also all disabled by default:

-   `WITH_GL_INFO` --- Build the @ref magnum-gl-info "magnum-gl-info"
    executable, which provides information about the engine OpenGL
    capabilities. Enables building of one of the windowless application
    libraries based on the target platform.
-   `WITH_AL_INFO` --- Build the @ref magnum-al-info "magnum-al-info"
    executable, which provides information about the engine OpenAL
    capabilities.
-   `WITH_DISTANCEFIELDCONVERTER` --- Build the
    @ref magnum-distancefieldconverter "magnum-distancefieldconverter"
    executable for converting black&white images to distance field textures.
    Enables also building of the @ref TextureTools library. Available only on
    desktop GL. Enables building of one of the windowless application libraries
    based on the target platform.
-   `WITH_FONTCONVERTER` --- Build the @ref magnum-fontconverter "magnum-fontconverter"
    executable for converting fonts of different formats. Enables also building
    of the @ref Text library. Available only on desktop GL. Enables building of
    one of the windowless application libraries based on the target platform.
-   `WITH_IMAGECONVERTER` --- Build the @ref magnum-imageconverter "magnum-imageconverter"
    executable for converting images of different formats.

Some of these utilities operate with plugins and they search for them in the
default plugin locations. You can override these locations using the
`MAGNUM_PLUGINS_DIR` and `MAGNUM_PLUGINS_[DEBUG|RELEASE]_DIR` variables, much
like when using Magnum from dependent projects --- see @ref cmake for more
information. In particular, if you specify them as relative paths, the path
will be taken relative to executable location, which is useful for making
relocatable installations.

Note that each [namespace](namespaces.html) documentation, all @ref Platform
library documentation and the @ref GL::OpenGLTester class documentation contain
more detailed information about dependencies, availability on particular
platform and also guide how to enable given library for building and how to use
it with CMake.

This list covers only the core Magnum features, see also features offered by
@ref building-corrade-features "Corrade",
@ref building-plugins-features "Magnum Plugins",
@ref building-integration-features "Magnum Integration",
@ref building-extras-features "Magnum Extras" and
@ref building-examples-features "Magnum Examples".

@subsection building-tests Building and running tests

If you want to build also the tests (which are not built by default), enable
`BUILD_TESTS` in CMake. The tests use Corrade's
@ref Corrade::TestSuite "TestSuite" framework and can be run either manually
(the binaries are located in `Test/` subdirectories in the build directory) or
using

@code{.sh}
ctest --output-on-failure
@endcode

in the build directory. On Windows the tests require the library to be
installed with DLLs accessible through @cb{.bat} %PATH% @ce. See the above
@ref building-windows "Windows documentation" for more information.

The @ref Audio library has tests which require OpenAL to be able to create a
context. That is the case on most platforms, so they are enabled by default.
In case it's not possible to have OpenAL context (such as when running
@ref CORRADE_TARGET_EMSCRIPTEN "Emscripten" tests under Node.js), you can
disable building of them with `BUILD_AL_TESTS`. The tests are suffixed with
`ALTest` so they can be also selectively included/excluded when running CTest,
e.g.:

@code{.sh}
ctest -E ALTest # run everything except tests requiring OpenAL context
@endcode

Platforms which have windowless GL context creation implemented (currently all
platforms except @ref CORRADE_TARGET_EMSCRIPTEN "Emscripten",
@ref CORRADE_TARGET_WINDOWS_RT "Windows RT" and
@ref CORRADE_TARGET_ANDROID "Android") can build also tests for OpenGL
functionality. You can enable them with `BUILD_GL_TESTS`. All GL tests are
suffixed with `GLTest` so they can be also selectively included/excluded when
running CTest, e.g.:

@code{.sh}
ctest -R GLTest # run only tests requiring OpenGL context
@endcode

@section building-doc Building documentation

The documentation (which you are currently reading) is written in
[Doxygen](http://doxygen.org) and additionally uses **LaTeX** for math
formulas. Documentation using the stock HTML theme can be build by running

@code{.sh}
doxygen
@endcode

in the root directory (i.e. where `Doxyfile` is). The resulting HTML
documentation will be in the `build/doc/` directory. You might need to create
the `build/` directory if it doesn't exist yet. If Corrade with generated
documentation is placed in the `corrade` directory next to `magnum`, the
documentation will be crosslinked with Corrade's one. If related projects
(`magnum-plugins`, `magnum-extras`, `magnum-integration` and `magnum-examples`,
see below) are places along these, their documentation will be also included in
generated output.

The documentation can be also generated using the
[m.css Doxygen theme](http://mcss.mosra.cz/doxygen/). Use `Doxyfile-mcss` for a
local build, the `Doxyfile-public` is meant for the publicly available
documentation at http://doc.magnum.graphics/magnum/. The resulting
documentation will be either in `build/doc-mcss/` or `build/doc-public/`.

@section building-windows-angle Building for ANGLE on Windows

Magnum is able to run on the ANGLE OpenGL-to-D3D translator. Download the code
from https://github.com/MSOpenTech/angle and use the provided Visual Studio
solution to build it. Put the resulting `libGLESv2`/`libEGL` libraries and
`GLES2`/`GLES3`/`EGL` includes to a location where CMake can find them or set
`CMAKE_PREFIX_PATH` accordingly. ANGLE supports only OpenGL ES, thus you need
to enable `TARGET_GLES`. The engine is built for OpenGL ES 2.0 by default,
switch to 3.0 by disabling `TARGET_GLES2`.

@code{.bat}
mkdir build-angle && cd build-angle
cmake .. ^
    -DCMAKE_PREFIX_PATH=<path-to-ANGLE-installation> ^
    -DTARGET_GLES=ON ^
    -DTARGET_GLES2=OFF ^
    -DWITH_SDL2APPLICATION=ON
cmake --build .
@endcode

See @ref platforms-gl-es-angle for more information about using ANGLE.

@section building-cross Cross-compiling

For cross-compiling you need to have *both* target and native version of
Corrade installed, because Corrade needs to run `corrade-rc` utility on the
host system as part of the build process. If native version of `corrade-rc` is
not found on the system, cross-compilation will fail.

You also need to have the toolchains submodule updated. Either run the
following command, or, if you build from source archive, download a snapshot of
the toolchains repository from https://github.com/mosra/toolchains and put the
contents in the `toolchains/` subdirectory.

@code{.sh}
git submodule update --init
@endcode

Note that CMake for some reason treats `CMAKE_PREFIX_PATH` and
`CMAKE_INSTALL_PREFIX` differently while cross-compiling and you may need to
add dependency paths to both `CMAKE_PREFIX_PATH` and `CMAKE_FIND_ROOT_PATH` to
make it able to find the dependencies.

@subsection building-cross-winrt Cross-compiling for Windows RT

As said above, you need a native build of the `corrade-rc` executable and
@ref building-corrade-cross-winrt "Corrade built for Windows RT". The below
script assumes that native Corrade build is installed in `C:/Sys` and the
installation path for WinRT dependencies is in `C:/Sys-winrt`.

You need at least Windows 8.1, Visual Studio 2015 and Windows 8.1 Store/Phone
SDK installed. Windows RT applications support OpenGL only through ANGLE, which
is currently limited to OpenGL ES. Download and build ANGLE
@ref building-windows-angle "according to the instructions above", but use
project files from the `winrt/` directory instead. Starting with version 2.0.4,
SDL has support for WinRT applications --- download the source from
https://www.libsdl.org/download-2.0.php and use project files from the
`VisualC-WinRT` directory. Because WinRT applications run in a sandbox, it's
recommended to build the library as static so you don't have to bundle all the
DLLs. Example:

@code{.bat}
mkdir build-winrt && cd build-winrt
cmake .. ^
    -DCMAKE_SYSTEM_NAME=WindowsStore ^
    -DCMAKE_SYSTEM_VERSION=10 ^
    -DCORRADE_RC_EXECUTABLE="C:/Sys/bin/corrade-rc.exe" ^
    -DCMAKE_INSTALL_PREFIX="C:/Sys-winrt" ^
    -DBUILD_STATIC=ON ^
    -DWITH_SDL2APPLICATION=ON ^
    -G "Visual Studio 14 2015" ..
cmake --build .
@endcode

Change `WindowsStore` to `WindowsPhone` if you want to build for Windows Phone
instead. When done, you can install the package using
@cb{.bat} cmake --build . --target install @ce to make it available to
depending projects.

See @ref platforms-windows for more information about building your projects
for WinRT.

@subsection building-cross-win Cross-compiling for Windows using MinGW-w64

@note This guide is tailored mainly for cross-compiling from ArchLinux. For
    this system there is also a prepared `mingw-w64-magnum` development package
    in `package/archlinux`, named `PKGBUILD-mingw-w64`. See
    @ref building-packages-arch "above" for more information.

You will need a MinGW-w64 version of the compiler, i.e. the `mingw-w64-gcc`
ArchLinux package, and also
@ref building-corrade-cross-win "Corrade built for MinGW".

Create build directories for 32b/64b build and run `cmake` and the build
command in them. You may need to modify the `basic-mingw-w64-32.cmake` /
`basic-mingw-w64-64.cmake` files and `CMAKE_INSTALL_PREFIX` to suit your
distribution filesystem hierarchy and also specify path where Corrade is
installed in `CMAKE_PREFIX_PATH`.

@code{.sh}
mkdir build-mingw-w64-32 && cd build-mingw-w64-32
cmake .. \
    -DCMAKE_TOOLCHAIN_FILE=../toolchains/archlinux/basic-mingw-w64-32.cmake \
    -DCMAKE_INSTALL_PREFIX=/usr/i686-w64-mingw32
cmake --build .
@endcode

@code{.sh}
mkdir build-mingw-w64-64 && cd build-mingw-w64-64
cmake .. \
    -DCMAKE_TOOLCHAIN_FILE=../toolchains/archlinux/basic-mingw-w64-64.cmake \
    -DCMAKE_INSTALL_PREFIX=/usr/x86_64-w64-mingw32
cmake --build .
@endcode

Then you can install the package using @cb{.sh} cmake --build . --target install @ce
to make it available to depending projects.

See @ref platforms-windows for more information about building your projects
for Windows.

@subsection building-cross-emscripten Cross-compiling for Emscripten

You will need [Emscripten](http://kripken.github.io/emscripten-site/) installed
and configured and
@ref building-corrade-cross-emscripten "Corrade built for Emscripten". The
toolchains require CMake 3.7 or newer to properly set compiler and linker
flags.

There are two toolchain files. The `generic/Emscripten.cmake` is for the
classical (asm.js) build, the `generic/Emscripten-wasm.cmake` is for a
WebAssembly build. Don't forget to adapt `EMSCRIPTEN_PREFIX` variable in
`generic/Emscripten*.cmake` to path where Emscripten is installed; you can also
pass it explicitly on command-line using `-DEMSCRIPTEN_PREFIX`. Default is
`/usr/lib/emscripten`. Emscripten supports dynamic libraries only to simplify
porting and they are generally slower, thus `BUILD_STATIC` is implicitly
enabled.

Then create build directory and run `cmake` and the build command in it.

WebGL 1.0 (GLES 2.0 equivalent) is enabled by default, switch to 2.0 (GLES 3.0
equivalent) by disabling `TARGET_GLES2`. If you enable one of the
@ref magnum-gl-info or @ref magnum-al-info utilities, you can override their
install location by setting `MAGNUM_DEPLOY_PREFIX` --- putting them for example
in your webserver root.

@code{.sh}
mkdir build-emscripten && cd build-emscripten
cmake .. \
    -DCMAKE_TOOLCHAIN_FILE="../toolchains/generic/Emscripten.cmake" \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_PREFIX_PATH=/usr/lib/emscripten/system \
    -DCMAKE_INSTALL_PREFIX=/usr/lib/emscripten/system \
    -DMAGNUM_DEPLOY_PREFIX=/srv/http/magnum \
    -DWITH_SDL2APPLICATION=ON
cmake --build .
@endcode

@note
    If you set `CMAKE_INSTALL_PREFIX` to a path contained in
    `EMSCRIPTEN_TOOLCHAIN_PATH` and dependencies are installed there as well,
    things should "just work". Otherwise you might get the following error:
@note <pre>CMake Error at .../Modules/FindPackageHandleStandardArgs.cmake:138 (message):
  Could NOT find Corrade (missing: CORRADE_INCLUDE_DIR
  _CORRADE_CONFIGURE_FILE)</pre>
@note
    This can be solved by adding the location where Corrade is installed to
    `CMAKE_PREFIX_PATH` or `CMAKE_FIND_ROOT_PATH`.

Then you can install the library using @cb{.sh} cmake --build . --target install @ce
to make it available to depending projects.

If you have Node.js installed, you can also build and run unit tests using
`ctest`. See the `BUILD_TESTS` option @ref building-tests "above".

For ArchLinux there are also prepared package files in `package/archlinux`,
named `PKGBUILD-emscripten`, `PKGBUILD-emscripten-webgl2`,
`PKGBUILD-emscripten-noopt`, `PKGBUILD-emscripten-noopt-webgl2`,
`PKGBUILD-emscripten-wasm` and `PKGBUILD-emscripten-wasm-webgl2`, see
@ref building-packages-arch "above" for more information. The first two are for
WebGL 1 / WebGL 2 optimized asm.js build (*slow* to compile), the second for
unoptimized build (faster to compile) and the third for WebAssembly build.

See @ref platforms-html5 for more information about building your projects for
Emscripten.

@subsection building-cross-ios Cross-compiling for iOS

You will need macOS with Xcode installed.

Set `CMAKE_OSX_ROOT` to the SDK you want to target and enable all desired
architectures in `CMAKE_OSX_ARCHITECTURES`. Be sure to set
`CMAKE_INSTALL_PREFIX` to prefix where you store other iOS dependencies such as
@ref building-corrade-cross-ios "Corrade built for iOS" or a SDL2 iOS build.

As every application is in its own sandbox, it doesn't make sense to build
shared libraries (although it is supported). Enable `BUILD_STATIC` to build
static libraries. Dynamically loaded plugins are not supported on iOS at the
moment, thus `BUILD_PLUGINS_STATIC` is implicitly enabled. OpenGL ES 2.0 is
enabled by default, switch to 3.0 by disabling `TARGET_GLES2`.

Please note that `BUILD_MULTITHREADED` is supported only since Xcode 7.3 and
doesn't work on `i386` iOS Simulator, you need to disable it in order to build
for older platforms.

@code{.sh}
mkdir build-ios && cd build-ios
cmake .. \
    -DCMAKE_TOOLCHAIN_FILE=../toolchains/generic/iOS.cmake \
    -DCMAKE_OSX_SYSROOT=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk \
    -DCMAKE_OSX_ARCHITECTURES="arm64;armv7;armv7s" \
    -DCMAKE_INSTALL_PREFIX=~/ios-libs \
    -DBUILD_STATIC=ON \
    -DBUILD_PLUGINS_STATIC=ON \
    -DTARGET_GLES2=OFF \
    -DWITH_SDL2APPLICATION=ON \
    -G Xcode
cmake --build .
@endcode

Then you can install the library using @cb{.sh} cmake --build . --target install @ce
to make it available to depending projects.

See @ref platforms-ios documentation for more information about building your
projects for iOS.

@subsection building-cross-android Crosscompiling for Android

You will need [Android NDK](https://developer.android.com/ndk/) installed and
configured and @ref building-corrade-cross-android "Corrade built for Android".
CMake 3.7 is required, as it has Android support builtin. The supported
toolchain is now Clang with libc++, GCC is not supported anymore.

@attention
    You might want to grab at least CMake 3.9.2 instead of just 3.7, as it
    [fixes an issue with the Clang toolchain](https://gitlab.kitware.com/cmake/cmake/issues/17253).

Create a build directory and run `cmake` and the build command in it. Set
`CMAKE_SYSTEM_NAME` to `Android` to enable the crosscompilation,
`CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION` and `CMAKE_ANDROID_STL_TYPE` to use Clang
with libc++, `CMAKE_SYSTEM_VERSION` to minimal API version level you wish to
use and `CMAKE_ANDROID_ARCH_ABI` to target platform ABI. Check the
[CMake Android cross-compiling documentation](https://cmake.org/cmake/help/latest/manual/cmake-toolchains.7.html#cross-compiling-for-android)
for further information.

If you set `CMAKE_INSTALL_PREFIX` to `/usr` subdirectory of the particular
Android platform sysroot, the package will get found automatically when
compiling subprojects. Gradle and other Android buildsystems expect
platform-independent includes and other files to be stored in a central
location, you can set `MAGNUM_INCLUDE_INSTALL_PREFIX` to `/usr` subdirectory of
the global NDK sysroot. Another option is to explicitly set `CMAKE_PREFIX_PATH`
to the install location in depending projects.

Note that `BUILD_STATIC` is implicitly enabled, because manually loading all
depending shared libraries using JNI would be too inconvenient. The engine is
built for OpenGL ES 2.0 by default, switch  to 3.0 by disabling `TARGET_GLES2`.

@code{.sh}
mkdir build-android-arm64 && cd build-android-arm64
cmake .. \
    -DCMAKE_SYSTEM_NAME=Android \
    -DCMAKE_SYSTEM_VERSION=22 \
    -DCMAKE_ANDROID_ARCH_ABI=arm64-v8a \
    -DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=clang \
    -DCMAKE_ANDROID_STL_TYPE=c++_static \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_INSTALL_PREFIX=/opt/android-ndk/platforms/android-22/arch-arm/usr \
    -DMAGNUM_INCLUDE_INSTALL_PREFIX=/opt/android-ndk/sysroot/usr \
    -DTARGET_GLES2=OFF \
    -DWITH_ANDROIDAPPLICATION=ON
cmake --build .
@endcode

Then you can install the library using @cb{.sh} cmake --build . --target install @ce
to make it available to depending projects.

For ArchLinux there is also a prepared package file in `package/archlinux/`,
named `PKGBUILD-android-arm64`; see @ref building-packages-arch "above" for
more information.

@attention
    On Windows it's possible that you get the following CMake error when
    configuring the project:
@attention
    <blockquote>
    CMAKE_SYSTEM_NAME is 'Android' but 'NVIDIA Nsight Tegra Visual Studio
    Edition' is not installed.
    </blockquote>
@attention
    This is because MSVC as the default generator on Windows is not able to
    build arbitrary Android projects. To fix it, use a different generator (for
    example Ninja, by passing `-G Ninja` to CMake).

See @ref platforms-android for more information about building your projects
for Android.

@section building-ci Continuous Integration

@subsection building-ci-travis Travis

In `package/ci/` there is a `travis.yml` file with Linux GCC 4.7, macOS, Linux
desktop GLES2/GLES3, iOS GLES2/GLES3, Emscripten WebGL1/WebGL2, Android
GLES2/GLES3, AddressSanitizer and ThreadSanitizer configuration. Online at
https://travis-ci.org/mosra/magnum.

@subsection building-ci-appveyor AppVeyor

In `package/ci/` there is an `appveyor.yml` file with Windows desktop MSVC,
MinGW, Windows desktop GLES2/GLES3 and Windows RT GLES2/GLES3 configuration.
Online at https://ci.appveyor.com/project/mosra/magnum.

@subsection building-ci-coverage Codecov.io

Linux, Linux GLES, macOS and Windows MinGW builds contribute to a combined code
coverage report, available online at https://codecov.io/gh/mosra/magnum.
*/
}