CMake: refactor and reformat CMake files

- raise minimum CMake version from 2.6.3 to 3.2.3 (Jun 01, 2015)
- indent all CMake files according to the CMP (2 col.)
- refactor FLTK version number definitions and usage
- unify CMake and autoconf/configure variable names:
  - FL_VERSION -> FLTK_VERSION
  - FL_MAJOR_VERSION -> FLTK_VERSION_MAJOR
  - etc. for _MINOR_ and _PATCH_, respectively
  - note: this does not affect FL_VERSION etc. in source code
- generate "export headers" for all libraries (experimental: OFF)
- port some forgotten goodies from branch-1.3 to master
- merge and improve macro 'create_example' (WIP)
- remove "temporary" options and code for older CMake versions
- include and use 'GenerateExportHeader' (experimental, WIP: OFF)
  - note: created header files are not yet used
- build only *one* DLL with Visual Studio (tested, works)
  - similar to the bundled IDE projects in 1.3.x
- add some dynamically linked test/demo programs ('*-shared')
  if shared libraries are built (WIP)
- split 'macros.cmake': use one file per macro

1 files changed, 55 insertions, 0 deletions

diff --git a/CMake/FLTK-Functions.cmake b/CMake/FLTK-Functions.cmake
new file mode 100644
index 000000000..cf7b0ae1a
--- /dev/null
+++ b/CMake/FLTK-Functions.cmake
@@ -0,0 +1,55 @@
+#
+# FLTK-Functions.cmake
+# Written by Michael Surette
+#
+# Copyright 1998-2020 by Bill Spitzak and others.
+#
+# This library is free software. Distribution and use rights are outlined in
+# the file "COPYING" which should have been included with this file.  If this
+# file is missing or damaged, see the license at:
+#
+#     https://www.fltk.org/COPYING.php
+#
+# Please see the following page on how to report bugs and issues:
+#
+#     https://www.fltk.org/bugs.php
+#
+
+#######################################################################
+# functions used by the build system and exported for the end-user
+#######################################################################
+
+# USAGE: FLTK_RUN_FLUID TARGET_NAME "FLUID_SOURCE [.. FLUID_SOURCE]"
+
+function (FLTK_RUN_FLUID TARGET SOURCES)
+  set (CXX_FILES)
+  foreach (src ${SOURCES})
+    if ("${src}" MATCHES "\\.fl$")
+      string(REGEX REPLACE "(.*).fl" \\1 basename ${src})
+      add_custom_command(
+        OUTPUT "${basename}.cxx" "${basename}.h"
+        COMMAND fluid -c ${CMAKE_CURRENT_SOURCE_DIR}/${src}
+        DEPENDS ${src}
+        MAIN_DEPENDENCY ${src}
+      )
+      list (APPEND CXX_FILES "${basename}.cxx")
+    endif ("${src}" MATCHES "\\.fl$")
+    set (${TARGET} ${CXX_FILES} PARENT_SCOPE)
+  endforeach ()
+endfunction (FLTK_RUN_FLUID TARGET SOURCES)
+
+#######################################################################
+
+# sets the bundle icon for OSX bundles
+
+function (FLTK_SET_BUNDLE_ICON TARGET ICON_PATH)
+  get_filename_component (ICON_NAME "${ICON_PATH}" NAME)
+  set_target_properties ("${TARGET}" PROPERTIES
+    MACOSX_BUNDLE_ICON_FILE "${ICON_NAME}"
+    RESOURCE "${ICON_PATH}"
+  )
+endfunction (FLTK_SET_BUNDLE_ICON TARGET ICON_PATH)
+
+#
+# End of file
+#