Remove hardcoded version numbers: part 1

The goal is to change the version number for a new release only in
CMakeLists.txt. This is the first step.

Details:

- CMake/gen_config.cmake: this new file is included to generate the
  header files config.h (private, root directory), and FL/fl_config.h
  (public, can be installed). This file implements also ABI version
  checks (removed from FL/Enumerations.H and with more checks).
  Warnings are issued if the chosen ABI version is invalid.
- CMake/export.cmake: code to generate 'config.h' was moved to
  CMake/gen_config.cmake.
- CMake/options.cmake: set default of FLTK_BUILD_FORMS=OFF + comments
- CMakeLists.txt: move generation of FL/fl_config.h to gen_config.cmake,
  add API and ABI versions to CMake summary,
- FL/Enumerations.H: remove most of the version number details which
  are now included in FL/fl_config.h. This needed also some doxygen
  related changes.
- README.CMake.txt: improve docs of FL_ABI_VERSION and some more.
  Reflect the new default of CMake option FLTK_BUILD_FORMS (OFF).
- documentation/Doxyfile.in: add FL/fl_config.h to file list. This
  file is created in the build tree (and may be "installed").
- fl_config.h.in: add version number details that have been moved here
  from Enumerations.H (used to generate FL/fl_config.h).

1 files changed, 5 insertions, 5 deletions

diff --git a/CMake/options.cmake b/CMake/options.cmake
index 8411b92ec..3ff6d06f5 100644
--- a/CMake/options.cmake
+++ b/CMake/options.cmake
@@ -75,9 +75,9 @@ add_definitions(${FLTK_ARCHFLAGS})
 #######################################################################
 set(FLTK_ABI_VERSION ""
   CACHE STRING
-  "FLTK ABI Version FL_ABI_VERSION: 1xxyy for 1.x.y (xx,yy with leading zero)"
+  "FLTK ABI Version FL_ABI_VERSION: 1xxyy for 1.x.y (xx,yy with leading zeroes)"
 )
-set(FL_ABI_VERSION ${FLTK_ABI_VERSION})
+# see also CMake/gen_config.cmake
 
 #######################################################################
 #  Select MSVC (Visual Studio) Runtime: DLL (/MDx) or static (/MTx)
@@ -201,8 +201,8 @@ if(FLTK_USE_BUNDLED_PNG)
 
   # Definitions for 'config.h' - do we still need this?
   # See also png/CMakeLists.txt (target_compile_definitions).
-  # Note: config.h is generated by either configure or CMake,
-  # hence we should support it in 1.4.x (may be changed in 1.5.0)
+  # Note: config.h is generated by CMake (or configure in 1.4), hence
+  # we support it in 1.4.x, but this may be changed in 1.5.0. (?)
 
   set(HAVE_PNG_H 1)
   set(HAVE_PNG_GET_VALID 1)
@@ -439,7 +439,7 @@ option(FLTK_BUILD_SHARED_LIBS
 option(FLTK_OPTION_PRINT_SUPPORT      "allow print support"        ON)
 option(FLTK_OPTION_FILESYSTEM_SUPPORT "allow file system support"  ON)
 
-option(FLTK_BUILD_FORMS        "Build forms compatibility library" ON)
+option(FLTK_BUILD_FORMS        "Build forms compatibility library" OFF)
 option(FLTK_BUILD_FLUID        "Build FLUID"                       ON)
 option(FLTK_BUILD_FLTK_OPTIONS "Build fltk-options"                ON)
 option(FLTK_BUILD_EXAMPLES     "Build example programs"            OFF)