Add: create bundles via CPack

CPack works closely together with CMake to do the right thing in
terms of bundling (called 'package'). This generates all the
packaging we need, and some more.

cmake/InstallAndPackage.cmake

@@ -0,0 +1,109 @@
+# If requested, use FHS layout; otherwise fall back to a flat layout.
+if (OPTION_INSTALL_FHS)
+    set(BINARY_DESTINATION_DIR "bin")
+    set(DATA_DESTINATION_DIR "share/games/openttd")
+    set(DOCS_DESTINATION_DIR "share/doc/openttd")
+    set(MAN_DESTINATION_DIR "share/man/openttd")
+else (OPTION_INSTALL_FHS)
+    set(BINARY_DESTINATION_DIR ".")
+    set(DATA_DESTINATION_DIR ".")
+    set(DOCS_DESTINATION_DIR ".")
+    set(MAN_DESTINATION_DIR ".")
+endif (OPTION_INSTALL_FHS)
+
+install(TARGETS openttd
+        RUNTIME
+            DESTINATION ${BINARY_DESTINATION_DIR}
+            COMPONENT Runtime
+        )
+
+install(DIRECTORY
+                ${CMAKE_BINARY_DIR}/lang
+                ${CMAKE_BINARY_DIR}/baseset
+                ${CMAKE_SOURCE_DIR}/bin/ai
+                ${CMAKE_SOURCE_DIR}/bin/game
+                ${CMAKE_SOURCE_DIR}/bin/scripts
+        DESTINATION ${DATA_DESTINATION_DIR}
+        COMPONENT language_files)
+
+install(FILES
+                ${CMAKE_SOURCE_DIR}/COPYING.md
+                ${CMAKE_SOURCE_DIR}/README.md
+                ${CMAKE_SOURCE_DIR}/changelog.txt
+                ${CMAKE_SOURCE_DIR}/docs/multiplayer.md
+                ${CMAKE_SOURCE_DIR}/known-bugs.txt
+        DESTINATION ${DOCS_DESTINATION_DIR}
+        COMPONENT docs)
+
+# A Linux manual only makes sense when using FHS. Otherwise it is a very odd
+# file with little context to what it is.
+if (OPTION_INSTALL_FHS)
+    install(FILES
+                    ${CMAKE_SOURCE_DIR}/docs/openttd.6
+            DESTINATION ${MAN_DESTINATION_DIR}
+            COMPONENT manual)
+endif (OPTION_INSTALL_FHS)
+
+# TODO -- Media files
+# TODO -- Menu files
+
+if (CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64")
+    set(ARCHITECTURE "amd64")
+else (CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64")
+    string(TOLOWER "${CMAKE_SYSTEM_PROCESSOR}" ARCHITECTURE)
+endif (CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64")
+
+# Windows is a bit more annoying to detect; using the size of void pointer
+# seems to be the most robust.
+if (WIN32)
+    if (CMAKE_SIZEOF_VOID_P EQUAL 8)
+        set(ARCHITECTURE "win64")
+    else (CMAKE_SIZEOF_VOID_P EQUAL 8)
+        set(ARCHITECTURE "win32")
+    endif (CMAKE_SIZEOF_VOID_P EQUAL 8)
+endif (WIN32)
+
+set(CPACK_SYSTEM_NAME "${ARCHITECTURE}")
+
+set(CPACK_PACKAGE_NAME "openttd")
+set(CPACK_PACKAGE_VENDOR "OpenTTD")
+set(CPACK_PACKAGE_DESCRIPTION "OpenTTD")
+set(CPACK_PACKAGE_DESCRIPTION_SUMMARY "OpenTTD")
+set(CPACK_PACKAGE_HOMEPAGE_URL "https://www.openttd.org/")
+set(CPACK_PACKAGE_CONTACT "OpenTTD <info@openttd.org>")
+set(CPACK_PACKAGE_INSTALL_DIRECTORY "OpenTTD")
+set(CPACK_PACKAGE_CHECKSUM "SHA256")
+set(CPACK_RESOURCE_FILE_LICENSE "${CMAKE_SOURCE_DIR}/COPYING.md")
+set(CPACK_RESOURCE_FILE_README "${CMAKE_SOURCE_DIR}/README.md")
+set(CPACK_MONOLITHIC_INSTALL YES)
+set(CPACK_PACKAGE_EXECUTABLES "openttd;OpenTTD")
+set(CPACK_STRIP_FILES YES)
+set(CPACK_OUTPUT_FILE_PREFIX "bundles")
+
+if (APPLE)
+    set(CPACK_GENERATOR "Bundle")
+    include(PackageBundle)
+
+    set(CPACK_PACKAGE_FILE_NAME "openttd-#CPACK_PACKAGE_VERSION#-macosx")
+elseif (WIN32)
+    set(CPACK_GENERATOR "ZIP;NSIS")
+    include(PackageNSIS)
+
+    set(CPACK_PACKAGE_FILE_NAME "openttd-#CPACK_PACKAGE_VERSION#-windows-${CPACK_SYSTEM_NAME}")
+elseif (UNIX)
+    # With FHS, we can create deb/rpm/... Without it, they would be horribly broken
+    # and not work. The other way around is also true; with FHS they are not
+    # usable, and only flat formats work.
+    if (OPTION_INSTALL_FHS)
+        set(CPACK_GENERATOR "DEB")
+        include(PackageDeb)
+    else (OPTION_INSTALL_FHS)
+        set(CPACK_GENERATOR "TXZ")
+    endif (OPTION_INSTALL_FHS)
+
+    set(CPACK_PACKAGE_FILE_NAME "openttd-#CPACK_PACKAGE_VERSION#-linux-${CPACK_SYSTEM_NAME}")
+else ()
+    message(FATAL_ERROR "Unknown OS found for packaging; please consider creating a Pull Request to add support for this OS.")
+endif ()
+
+include(CPack)