magnum/doc/building.dox

/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013 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"),
    to deal in the Software without restriction, including without limitation
    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
    in all copies or substantial portions of the Software.

    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
    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
    DEALINGS IN THE SOFTWARE.
*/

namespace Magnum {

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

@tableofcontents

Minimal set of tools and libraries required for building is:

- C++ compiler with good C++11 support. Currently there are two compilers
  which are tested to support everything needed: **GCC** >= 4.6 and **Clang**
  >= 3.1. On Windows you can use **MinGW**, Visual Studio compiler still lacks
  some needed features.
- **CMake** >= 2.8.8
- **Corrade** - Plugin management and utility library. See
  @ref building-corrade "Corrade download and installation guide" for more
  information.
- **OpenAL** - By default needed by Audio library, but you can disable building
  of it by setting `WITH_AUDIO` to `OFF` (see below).

@section 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
compressed archive or use the command line:

    git clone git://github.com/mosra/magnum.git

@section building-compilation Compilation, installation

Relevant information about CMake usage was described in
@ref building-corrade "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 OSs, the library (for example with support for GLUT applications)
can be built and installed using these four commands:

    mkdir -p build && cd build
    cmake .. \
        -DCMAKE_INSTALL_PREFIX=/usr \
        -DWITH_GLUTAPPLICATION=ON
    make
    make install

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

@subsection building-windows Using QtCreator and CMake GUI (on Windows)

On Windows, if you don't want to touch the command-line, the easiest way is to
install QtCreator (just QtCreator, you don't need the full Qt SDK) and
configure it to use MinGW and CMake.

For most convenient usage it's best to install (or copy/paste) all library
dependencies into directory where MinGW is installed (e.g. `C:/MinGW/`),
following proper filesystem hierarchy, i.e. headers into `include/` and
binaries into `bin/` or `lib/`. CMake will then have no problem finding them
and you won't need to explicitly specify path to each one.

Then just open project's root `CMakeLists.txt` file within QtCreator. It then
asks you where to create build directory, allows you to specify initial CMake
parameters and then you can just press *Configure* and everything is be ready
to be built.

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

For most convenient usage it's best to set `CMAKE_INSTALL_PREFIX` to directory
where MinGW is installed (e.g. `C:/MinGW/`) and add `C:/MinGW/bin` and
`C:/MinGW/lib` to `PATH`. Installation to given prefix can be then done from
within QtCreator by adding new `make install` build rule.

@subsubsection building-windows-troubleshooting Windows troubleshooting

If CMake isn't able to find dependencies (e.g. %Corrade is not found) and you
have installed them to MinGW directory, point to `CMAKE_FIND_ROOT_PATH` to
MinGW installation prefix, e.g. specify `-DCMAKE_FIND_ROOT_PATH=C:/MinGW/`
CMake parameter.

See also Corrade's @ref building-corrade-windows-troubleshooting "troubleshooting section".

@subsection building-features Enabling or disabling features

The libraries are build as shared by default. If you are developing for
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. If you
plan to use them 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.

%Magnum by default does not install `FindMagnum.cmake`, as you should bundle
the module with your code instead of depending on it being in system location.
You can install it by enabling `WITH_FIND_MODULE`.

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. 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 `TARGET_*` CMake
parameters you can target other platforms. Note that some features are
available for desktop OpenGL only, see @ref requires-gl.

 - `TARGET_GLES` - Target OpenGL ES.
 - `TARGET_GLES2` - Target OpenGL ES 2.0. Currently enabled by default when
   `TARGET_GLES` is set, as no customer OpenGL ES 3.0 platform exists yet.
 - `TARGET_DESKTOP_GLES` - Target OpenGL ES on desktop, i.e. use OpenGL ES
   emulation in desktop OpenGL library. Might not be supported in all drivers.

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

By default the engine is built with everything except application libraries
(see below). Using `WITH_*` CMake parameters you can specify which parts will
be built and which not:

 - `WITH_AUDIO` - Audio library. Requires **OpenAL** library.
 - `WITH_DEBUGTOOLS` - DebugTools library. Enables also building of MeshTools,
   Primitives, SceneGraph, Shaders and Shapes libraries.
 - `WITH_MESHTOOLS` - MeshTools library. Enabled automatically if `WITH_DEBUGTOOLS`
   is enabled.
 - `WITH_PRIMITIVES` - Primitives library. Enabled automatically if `WITH_DEBUGTOOLS`
   is enabled.
 - `WITH_SCENEGRAPH` - SceneGraph library. Enabled automatically if `WITH_DEBUGTOOLS`
   or `WITH_SHAPES` is enabled.
 - `WITH_SHADERS` - Shaders library. Enabled automatically if `WITH_DEBUGTOOLS`
   is enabled.
 - `WITH_SHAPES` - Shapes library. Enables also building of SceneGraph library.
   Enabled automatically if `WITH_DEBUGTOOLS` is enabled.
 - `WITH_TEXT` - Text library. Enables also building of TextureTools library.
 - `WITH_TEXTURETOOLS` - TextureTools library. Enabled automatically if `WITH_TEXT`
   or `WITH_DISTANCEFIELDCONVERTER` is enabled.
 - `WITH_MAGNUMINFO` - `magnum-info` executable, provides information about the
   engine and OpenGL capabilities.
 - `WITH_DISTANCEFIELDCONVERTER` - `magnum-distancefield` executable for
   converting black&white images to distance field textures. Enables also
   building of TextureTools library.

None of the @ref Platform "application libraries" is built by default (and you
need at least one). Choose the one which suits your requirements and your
platform best:

- `WITH_GLUTAPPLICATION` - @ref Platform::GlutApplication "GlutApplication",
  available only if targeting desktop OpenGL. Requires **GLUT** library.
- `WITH_GLXAPPLICATION` - @ref Platform::GlxApplication "GlxApplication".
  Available only if targetting desktop OpenGL or ES desktop emulation, not
  available on Google Chrome Native Client or Emscripten. Requires **X11** and
  **GLX** libraries.
- `WITH_NACLAPPLICATION` - @ref Platform::NaClApplication "NaClApplication",
  available only if targeting Google Chrome Native Client.
- `WITH_SDL2APPLICATION` - @ref Platform::Sdl2Application "Sdl2Application".
  Available also on Emscripten, but not on Google Chrome Native Client.
  Requires **SDL2** library.
- `WITH_XEGLAPPLICATION` - @ref Platform::XEglApplication "XEglApplication",
  available only if targeting OpenGL ES (see above). Not available on Google
  Chrome Native Client or Emscripten. Requires **X11** and **EGL** libraries.
- `WITH_WINDOWLESSGLXAPPLICATION` - @ref Platform::WindowlessGlxApplication "WindowlessGlxApplication".
  Available only if targetting desktop OpenGL or ES desktop emulation, not
  available on Google Chrome Native Client or Emscripten. Requires **X11** and
  **GLX** libraries.
- `WITH_WINDOWLESSNACLAPPLICATION` - @ref Platform::WindowlessNaClApplication "WindowlessNaClApplication",
  available only if targeting Google Chrome Native Client.

@subsection building-tests Building and running unit tests

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

    ctest --output-on-failure

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

Platforms which have windowless context creation implemented (currently only
desktop Linux) can build also tests for OpenGL functionality. You can enable
them with `BUILD_GL_TESTS`.

@subsection building-doc Building documentation

The documentation (which you are currently reading) is written in **Doxygen**
(version 1.8 with Markdown support is used, but older versions should do good
job too) and additionally uses **TeX** for math formulas. The documentation can
be build by running

    doxygen

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

@section building-related Related projects

The engine itself is kept as small as possible with only little dependencies.
Additional functionality, often depending on external libraries, is provided in
separate repositories. Various importer plugins for image, audio and 3D model
formats are maintained in @ref building-plugins "Plugins repository",
Integration with various external math and physics libraries is provided by
@ref building-integration "Integration library".

@section building-packages Prepared packages

@subsection building-packages-arch ArchLinux packages

In `package/archlinux` directory is currently one PKGBUILD for Git development
build. The package is also in AUR under the same name.

There are also a few development PKGBUILDs in project root, which allow you to
build and install the package directly from source tree without downloading
anything. The native PKGBUILD also contains `check()` function which will run
all unit tests before packaging.

If you want to build with another compiler (e.g. Clang), run makepkg this way:

    CXX=clang++ makepkg

Development PKGBUILDs can detect when Clang is used and remove unsupported CXX
flags.

@section building-crosscompiling Crosscompiling

For crosscompiling 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, crosscompilation will fail.

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

    git submodule init
    git submodule update

@subsection building-cross-win Crosscompiling for Windows using MinGW

@note This guide is tailored mainly for crosscompiling from ArchLinux. For
this system there is also prepared `mingw32-magnum` development package in
root, named `PKGBUILD-mingw32`.

You will need MinGW32 versions of the compiler and all dependent libraries
(Corrade), i.e. these ArchLinux packages:

- `mingw32-gcc`, which depends on `mingw32-w32api` containing OpenGL headers
- `mingw32-runtime`
- `mingw32-corrade`

Then create build directory and run cmake and make. You may need to modify the
`basic-mingw32.cmake` file and `CMAKE_INSTALL_PREFIX` to suit your distribution
filesystem hierarchy.

    mkdir build-win
    cd build-win
    cmake .. \
        -DCMAKE_TOOLCHAIN_FILE=../toolchains/archlinux/basic-mingw32.cmake \
        -DCMAKE_INSTALL_PREFIX=/usr/i486-mingw32
    make

Then you can install the package using `make install` to make it available for
depending projects.

@subsection building-cross-nacl Crosscompiling for Google Chrome Native Client

You will need [Native Client SDK](https://developers.google.com/native-client/beta/sdk/download).
Tested version is `pepper_22`.

You can choose from either `glibc` or `newlib` toolchain. `Newlib` supports
only static linking, thus `BUILD_STATIC` is always enabled. Don't forget to
adapt `NACL_PREFIX` variable in `generic/NaCl-*-x86-32.cmake` and
`generic/NaCl-*-x86-64.cmake` to path where your SDK is installed. Default is
`/usr/nacl`. You may need to adapt also `NACL_TOOLCHAIN_PATH` so CMake is able
to find the compiler. NaCl currently supports only OpenGL ES 2, thus
`TARGET_GLES` and `TARGET_GLES2` is always enabled.

Then create build directories for x86-32 and x86-64 and run cmake and make in
them. The toolchains need access to its platform file, so be sure to properly
set **absolute** path to `modules/` directory containing `Platform/NaCl.cmake`.
Also adapt `CMAKE_INSTALL_PREFIX` to the same value as in `NACL_PREFIX` in
toolchain file.

    mkdir -p build-nacl-x86-32
    cd build-nacl-x86-32
    cmake .. \
        -DCMAKE_MODULE_PATH="/absolute/path/to/toolchains/modules" \
        -DCMAKE_TOOLCHAIN_FILE="../toolchains/generic/NaCl-glibc-x86-32.cmake" \
        -DCMAKE_BUILD_TYPE=Release \
        -DCMAKE_INSTALL_PREFIX=/usr/nacl \
        -DWITH_NACLAPPLICATION=ON \
        -DLIB_SUFFIX=/32
    make

    mkdir -p build-nacl-x86-64
    cd build-nacl-x86-64
    cmake .. \
        -DCMAKE_MODULE_PATH="/absolute/path/to/toolchains/modules" \
        -DCMAKE_TOOLCHAIN_FILE="../toolchains/generic/NaCl-glibc-x86-64.cmake" \
        -DCMAKE_BUILD_TYPE=Release \
        -DCMAKE_INSTALL_PREFIX=/usr/nacl \
        -DWITH_NACLAPPLICATION=ON
    make

Then you can install both versions using `make install` to make them available
for depending projects. The headers are shared by both versions.

For ArchLinux there are also prepared package files in root, named
`PKGBUILD-nacl-glibc` and `PKGBUILD-nacl-newlib`.

@subsection building-cross-emscripten Crosscompiling for Emscripten

You will need [Emscripten](https://github.com/kripken/emscripten/wiki/Tutorial)
installed and configured.

Don't forget to adapt `EMSCRIPTEN_PREFIX` variable in `generic/Emscripten.cmake`
to path where Emscripten is installed. Default is `/usr/emscripten`. Emscripten
supports dynamic only to simplify porting and they are generally slower, thus
`BUILD_STATIC` is implicitly enabled.

Then create build directory and run cmake and make in it. The toolchain needs
access to its platform file, so be sure to properly set **absolute** path to
`modules/` directory containing `Platform/Emscripten.cmake`. Default is
`/usr/emscripten`. Also set `CMAKE_INSTALL_PREFIX` to value which is contained
in `CMAKE_FIND_ROOT_PATH` in toolchain file.

    mkdir -p build-emscripten
    cd build-emscripten
    cmake .. \
        -DCMAKE_MODULE_PATH="/absolute/path/to/toolchains/modules" \
        -DCMAKE_TOOLCHAIN_FILE="../toolchains/generic/Emscripten.cmake" \
        -DCMAKE_BUILD_TYPE=Release \
        -DCMAKE_INSTALL_PREFIX=/usr/emscripten/system \
        -DWITH_SDL2APPLICATION=ON
    make

Then you can install the library using `make install` to make it available for
depending projects.

If you have Node.js installed, you can also build and run unit tests using
`ctest`. See `BUILD_TESTS` above.

*/

}