[Latest version of these instructions can be found at the SFML Wiki]

CMake allows your project to be built in various environments, including command-line make, Code::Blocks project files, Eclipse project files, etc. It's used in SFML 2.0.

In this tutorial we'll write a simple CMake configuration file with centralized version numbering, and see how to integrate SFML in it.

The source files

First, create a cmake_modules directory and copy FindSFML.cmake in it. FindXXXX is automatically searched by CMake's find_package command.

Then create a main.cpp, for instance:

#include "config.h"
#include <iostream>
#include <SFML/Window.hpp>
using namespace std;

int main(int argc, char* argv[]) {
  cout << "Version " << myproject_VERSION_MAJOR << "." << myproject_VERSION_MINOR << endl;

  sf::Window screen(sf::VideoMode(800, 600), "myproject");
  bool running = true;
  while (running) {
    screen.Display();
  }
}

We use a config.h file that is built by CMake, let's also create a config.h.in file:

#define myproject_VERSION_MAJOR @myproject_VERSION_MAJOR@
#define myproject_VERSION_MINOR @myproject_VERSION_MINOR@

And place your project license (such as the GNU GPL) in a file named COPYING.

CMake configuration

Let's describe our project configuration in the CMakeLists.txt file:

cmake_minimum_required(VERSION 2.6)
project(myproject)

# Set version information in a config.h file
set(myproject_VERSION_MAJOR 1)
set(myproject_VERSION_MINOR 0)
configure_file(
  "${PROJECT_SOURCE_DIR}/config.h.in"
  "${PROJECT_BINARY_DIR}/config.h"
  )
include_directories("${PROJECT_BINARY_DIR}")

# Define sources and executable
set(EXECUTABLE_NAME "myproject")
add_executable(${EXECUTABLE_NAME} main.cpp)


# Detect and add SFML
set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake_modules" ${CMAKE_MODULE_PATH})
find_package(SFML 1.6 REQUIRED system window graphics network audio)
target_link_libraries(${EXECUTABLE_NAME} ${SFML_LIBRARIES})


# Install target
install(TARGETS ${EXECUTABLE_NAME} DESTINATION bin)


# CPack packaging
include(InstallRequiredSystemLibraries)
set(CPACK_RESOURCE_FILE_LICENSE "${CMAKE_SOURCE_DIR}/COPYING")
set(CPACK_PACKAGE_VERSION_MAJOR "${myproject_VERSION_MAJOR}")
set(CPACK_PACKAGE_VERSION_MINOR "${myproject_VERSION_MINOR}")
include(CPack)

The interesting part is:

# Detect and add SFML
set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake_modules" ${CMAKE_MODULE_PATH})
find_package(SFML 1.6 REQUIRED system window graphics network audio)
target_link_libraries(${EXECUTABLE_NAME} ${SFML_LIBRARIES})
  • First we specify where we stored the FindSFML.cmake module.
  • Then we request CMake to look for it in the system, and search for the specified modules (here I specified them all).
  • Last, we tell CMake to link our executable with the SFML libraries that it just found.

Compilation

To build with Make and the GCC compiler on the command-line:

cd build/  # a separate directory so we can easily remove all the CMake work files
cmake ..  # generate Makefile's
make

To create Code::Blocks project files:

cmake .. -G "CodeBlocks - Unix Makefiles"

and open project.cbp with Code::Blocks.

Installation

CMake supports the classic:

make install

It also supports DESTDIR, useful in packaging:

make install DESTDIR=`pwd`/myworkdir

You can also define CMAKE_INSTALL_PREFIX when invoking cmake to change the default install path (/usr/local under Unix). DESTDIR would still override this setting.

Packaging

You then can use cpack to make a project release:

# Binary package:
cpack -C CPackConfig.cmake
# Source package:
cpack -C CPackSourceConfig.cmake

You will get a nice myproject-1.0.tar.gz, among others.

Further information

  • CMake has built-in help, for instance:
$ cmake --help-variable CMAKE_SOURCE_DIR
cmake version 2.8.5
  CMAKE_SOURCE_DIR
       The path to the top level of the source tree.

       This is the full path to the top level of the current CMake source
       tree.  For an in-source build, this would be the same as
       CMAKE_BINARY_DIR.
Posted Tue Nov 1 21:13:45 2011 Tags:

If you ever need to check a CVS history file's timestamp:

A4eb172bd|myaccount||Module/Dir|1.1|yopla.c

$ perl -e 'print unpack("N", pack("H8", "4eb172bd")) . "\n"'
1320252093
$ date -d "@1320252093"
Wed Nov  2 17:41:33 CET 2011
Posted Sun Nov 6 15:39:48 2011 Tags: