-set(CMAKE_DEBUG_POSTFIX "d" CACHE STRING "add a postfix, usually d on windows")
-set(CMAKE_RELEASE_POSTFIX "" CACHE STRING "add a postfix, usually empty on windows")
-set(CMAKE_RELWITHDEBINFO_POSTFIX "" CACHE STRING "add a postfix, usually empty on windows")
-set(CMAKE_MINSIZEREL_POSTFIX "" CACHE STRING "add a postfix, usually empty on windows")
+# We have some custom .cmake scripts not in the official distribution.
+set(CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/CMakeModules;${CMAKE_MODULE_PATH}")
+
+if(${CMAKE_VERSION} VERSION_GREATER 2.8.4)
+ # use official include provided by latest CMake
+ include(GNUInstallDirs)
+else(${CMAKE_VERSION} VERSION_GREATER 2.8.4)
+ # backward compatibility: use our own module for older cmake versions
+ include(OldGNUInstallDirs)
+endif(${CMAKE_VERSION} VERSION_GREATER 2.8.4)
+
+# Warning when build is not an out-of-source build.
+string(COMPARE EQUAL "${CMAKE_SOURCE_DIR}" "${CMAKE_BINARY_DIR}" InSourceBuild)
+if(InSourceBuild)
+ message(WARNING "Avoid building inside the source tree!")
+ message(WARNING "Create a separate build directory instead (i.e. 'fgbuild') and call CMake from there: ")
+ message(WARNING " mkdir ../fgbuild && cd ../fgbuild && cmake ${CMAKE_SOURCE_DIR}")
+endif(InSourceBuild)
+
+# System detection/default settings
+include( DetectDistro )
+include( DetectBrowser )
+
+set(CMAKE_DEBUG_POSTFIX "d" CACHE STRING "add a postfix, usually d on windows")
+set(CMAKE_RELEASE_POSTFIX "" CACHE STRING "add a postfix, usually empty on windows")
+set(CMAKE_RELWITHDEBINFO_POSTFIX "" CACHE STRING "add a postfix, usually empty on windows")
+set(CMAKE_MINSIZEREL_POSTFIX "" CACHE STRING "add a postfix, usually empty on windows")