Update two README files for 1.5.0

- remove configure related stuff
- improve documentation in these files

2 files changed, 60 insertions, 142 deletions

diff --git a/README.Cairo.txt b/README.Cairo.txt
index 0dc0b9ecc..723e561f0 100644
--- a/README.Cairo.txt
+++ b/README.Cairo.txt
@@ -1,5 +1,5 @@
 README.Cairo.txt - Cairo Window Support for FLTK
-----------------------------------------------------
+-------------------------------------------------
 
 
  CONTENTS
@@ -38,25 +38,22 @@ use the class Fl_Cairo_Window which sets up a Cairo context so the user
 progam can call Cairo drawing calls in their own drawing callback.
 
     CMake option name: FLTK_OPTION_CAIRO_WINDOW
-    Configure option : --enable-cairo
 
 Since FLTK 1.3 the library can also be configured to provide a Cairo context
-in all subclasses of Fl_Window. This is called "extended" Cairo support.
+in all subclasses of Fl_Window. This is called "extended" Cairo support and
+is not recommended for general use.
 
     CMake option name: FLTK_OPTION_CAIRO_EXT
-    Configure option : --enable-cairoext
 
 These two options provide users with an interface to use Cairo to draw
 into FLTK windows. FLTK does not use Cairo for rendering its own graphics
 with these two options. Both options must be enabled explicitly.
 
-
 Since FLTK 1.4 the new Wayland platform uses Cairo for all drawings.
 Under X11 drawing with Cairo rather than Xlib is a build option.
 The old "Fl_Cairo_Window support" is still available on all platforms.
 
     CMake option name: FLTK_GRAPHICS_CAIRO
-    Configure option : --enable-usecairo
 
 Full Cairo drawing is provided on Unix/Linux platforms. It is always used if
 Wayland (FLTK_BACKEND_WAYLAND) is enabled during the build. It is optional
@@ -97,10 +94,10 @@ drawing by itself (FLTK_GRAPHICS_CAIRO).
       to automatically making possible the use of a Cairo context
       in any FLTK window.
 
-    This feature must be enabled with 'configure --enable-cairoext' or the
-    CMake option FLTK_OPTION_CAIRO_EXT:BOOL=ON (Default: OFF).
+    This feature must be enabled explicitly with the CMake option
+    FLTK_OPTION_CAIRO_EXT:BOOL=ON (Default: OFF).
 
-(4) A new Cairo demo that is available in the test subdirectory.
+(4) A Cairo demo program in the test subdirectory.
 
 For more details, please have a look to the doxygen documentation,
 in the Modules section.
@@ -122,7 +119,8 @@ on the various supported operating systems.
         sudo apt install libcairo2-dev
 
     Then build fltk using the Cairo support option using:
-      cmake -G "Unix Makefiles" -D FLTK_OPTION_CAIRO_WINDOW:BOOL=ON -S <fltk_dir> -B <your_build_dir>
+
+      cmake -G "Unix Makefiles" -D FLTK_OPTION_CAIRO_WINDOW=ON -S <fltk_dir> -B <your_build_dir>
       cd <your_build_dir>
       make
 
@@ -134,26 +132,8 @@ on the various supported operating systems.
 
         sudo yum install cairo-devel
 
-    ..and then rebuild FLTK:
-
-        make distclean
-        ./configure --enable-cairo
-        make
-
-    If you get this error:
-
-        [..]
-        Linking cairo_test...
-        /usr/bin/ld: cannot find -lpixman-1
-        collect2: ld returned 1 exit status
-        make[1]: *** [cairo_test] Error 1
-
-    ..remove "-lpixman-1" from FLTK's makeinclude file, i.e. change this line:
+    ..and then rebuild FLTK (see above for CMake command and options).
 
-        -CAIROLIBS      = -lcairo -lpixman-1
-        +CAIROLIBS      = -lcairo
-
-    ..then another 'make' should finish the build without errors.
     You should be able to then run the test/cairo_test program.
 
     According to the Cairo site, "For Debian and Debian derivatives including
@@ -166,12 +146,9 @@ on the various supported operating systems.
     as well.
 
     As of Feb 2021 (FLTK 1.4.0) dependencies like pixman-1 will be detected by
-    configure or CMake automatically using pkg-config.
-
-    Note 1: CMake builds *require* the use of pkg-config.
+    CMake automatically using pkg-config.
 
-    Note 2: As of Feb 2021 autoconf/configure/make builds require pkg-config
-    as well.
+    Note: builds with Cairo and/or Wayland *require* pkg-config.
 
 
     3.2 Windows
@@ -181,11 +158,12 @@ on the various supported operating systems.
 
     3.3 macOS
     ----------
-    As under Linux you can use both build options, i.e. autoconf/make or CMake
-    to build FLTK with Cairo support. One option is to install Homebrew and
-    add the required libraries with `brew install ...'. It is always required
-    to install the "Xcode commandline tools" but a full installation of Xcode
-    is not necessary. If you choose to use Xcode you can generate the Xcode
+    As under Linux you can use CMake to build FLTK with Cairo support.
+
+    One option is to install Homebrew and add the required libraries with
+    `brew install ...'. It is always required to install the "Xcode
+    commandline tools" but a full installation of Xcode is not necessary.
+    If you choose to use Xcode you can generate the Xcode
     IDE files with CMake.
 
     The following instructions are intentionally terse. More detailed
@@ -200,16 +178,7 @@ on the various supported operating systems.
 
     With these tools installed it is already possible to download and build
     a current FLTK tarball or snapshot. All you need to do is unpack the
-    tarball and run `make' in the root directory. This will run `configure',
-    generate the necessary files, and build FLTK in its standard configuration.
-
-    Note 1: this requires an existing `configure' file which is included in
-    FLTK releases and snapshots but not in the FLTK Git repository.
-
-    Note 2: to build current FLTK downloaded from Git using configure + make
-    you need to run `autoconf' to generate 'configure'. If autoconf is not
-    available on your system you can download a FLTK snapshot, unpack it,
-    and copy the 'configure' file from the snapshot to your Git worktree.
+    tarball and cmake and make as described in README.CMake.txt.
 
 
     3.3.2 Install Homebrew for Cairo and other Library Support
@@ -232,9 +201,9 @@ on the various supported operating systems.
     other software (package) name to see if it can be installed. If yes, run
     `brew install cairo' (or other name) to install it.
 
-    Other helpful packages are 'autoconf' and other Unix (Linux) tools, for
-    instance 'git-gui' (installs 'gitk' and 'git gui' commands). The Xcode
-    commandline tools mentioned above install only the git commandline tool.
+    Other helpful packages are some Unix (Linux) tools, for instance 'git-gui'
+    (installs 'gitk' and 'git gui' commands). The Xcode commandline tools
+    mentioned above install only the git commandline tool.
 
 
     3.3.3 Install CMake and Build with CMake
diff --git a/README.Unix.txt b/README.Unix.txt
index 2cf9114a4..b2c572f58 100644
--- a/README.Unix.txt
+++ b/README.Unix.txt
@@ -17,16 +17,15 @@ README.Unix.txt - Building FLTK on Unix/Linux Systems
     2.7   HP-UX
     2.8   AIX
 
-  3   How to Build FLTK Using GCC
+  3   How to Build FLTK on Unix or Unix-like Systems
     3.1   Downloading and Unpacking
     3.2   Configuration and Build Systems
-    3.3   Configuring FLTK with autoconf and configure (deprecated)
-    3.4   Building FLTK
-    3.5   Testing FLTK
-    3.6   Installing FLTK
-    3.7   Creating new Projects
+    3.3   Building FLTK in a Nutshell
+    3.4   Testing FLTK
+    3.5   Installing FLTK
+    3.6   Creating Your Own Projects
 
-  4   Creating a new Project in Code::Blocks
+  4   Creating a New Project in Code::Blocks
 
 
 [*] TODO: we still need to write these chapters
@@ -272,8 +271,8 @@ you want to do so.
 
 
 
- 3  How to Build FLTK Using GCC
-================================
+ 3  How to Build FLTK on Unix or Unix-like Systems
+===================================================
 
 
  3.1  Downloading and Unpacking
@@ -285,8 +284,8 @@ The FLTK source code and documentation can be downloaded from:
 
 If you are familiar with "git" and like to stay current with your version,
 you will find the git access parameters at the bottom of that page.
-Unpack FLTK into a convenient location. I like to have everything in my
-dev directory. Change the following instructions to fit your preferences.
+Unpack FLTK into a convenient location, e.g. in your `dev` directory.
+Change the following instructions to fit your preferences.
 
   cd
   mkdir dev
@@ -296,114 +295,62 @@ dev directory. Change the following instructions to fit your preferences.
   cd fltk-1.x.y
 
 
- 3.2  Configuration and Build Systems
---------------------------------------
+ 3.2  Configuration and Building
+---------------------------------
 
-The following paragraphs describe the "classic" build system with autoconf,
-configure, and make that has been used to build FLTK up to version 1.3.x
-and can still be used with FLTK 1.4.x.
-
-However, the FLTK team recommend to use CMake which is the preferred build
-system generator since FLTK 1.4 used for all platforms (including Windows).
+Since FLTK 1.5 the only build system (generator) used by FLTK is CMake.
 CMake can be used to create the build system of your choice, for instance
 Makefiles, Ninja build files, Xcode or Visual Studio IDE projects etc..
 
--------------------------------------------------------------------
-  Note: usage of autotools, configure, and the included Makefiles
-  to build the FLTK library is deprecated since FLTK 1.4 and will
-  be removed in the next minor version (1.5).
-  Please consider using CMake instead, see README.CMake.txt.
--------------------------------------------------------------------
+Note: The "classic" build system with autoconf, configure, and Makefiles
+is no longer available.
 
 Please see README.CMake.txt for how to build FLTK and your application
-programs using CMake. You can stop reading here if you do this.
+programs using CMake.
 
 You can, of course, build FLTK with CMake and your own application(s)
 with your existing and well-known build system.
 
-If you like the "classic" build system more, continue reading the
-following chapters but please be aware that configure support will
-be removed in FLTK 1.5.
 
+ 3.3  Building FLTK in a Nutshell
+----------------------------------
 
- 3.3  Configuring FLTK with autoconf and configure (deprecated)
-----------------------------------------------------------------
-
--------------------------------------------------------------------
-  Note: usage of autotools, configure, and the included Makefiles
-  to build the FLTK library is deprecated since FLTK 1.4 and will
-  be removed in the next minor version (1.5).
-  Please consider using CMake instead, see README.CMake.txt.
--------------------------------------------------------------------
+Following are only basic commands, please see details in README.CMake.txt.
 
-If you got FLTK via git then you need one extra step. Otherwise skip
-over this part. Stay in your FLTK source-code directory and type:
+Building FLTK with all default parameters on your platform is easy.
+Stay in your FLTK source-code directory and type:
 
-  autoconf
+  cmake . -B build -D [ CMAKE_BUILD_TYPE=Debug ... more options ]
+  cmake --build build
 
-or
+The entire FLTK toolkit including many test programs will be built for you
+in the subdirectory `build`. No warnings should appear. If some do, please
+let the FLTK developer team know via the mailing list "fltk.general" or
+view the bug reporting guidelines at https://www.fltk.org/bugs.php .
 
-  make configure
 
-Both commands create the configure script for you.
-
-Now configure your FLTK installation:
-
-  ./configure
-
-Hint: Instead of executing `autoconf` and `configure` followed by `make`
-to build FLTK (see next section) you can also run `make` directly which
-will create and execute the 'configure' script with default parameters
-and build FLTK with the default configuration.
-
-ADVANCED: type "./configure --help" to get a complete list of optional
-configuration parameters. These should be pretty self-explanatory. Some
-more details can be found in README.txt.
-:END_ADVANCED
-
-The configuration script will check your machine for the required resources
-which you should have installed as described in the "Prerequisites" chapter.
-Review the "Configuration Summary", maybe take some notes.
-
-
- 3.4  Building FLTK
---------------------
-
-Now this is easy. Stay in your FLTK source-code directory and type:
-
-  make
-
-The entire FLTK toolkit including many test programs will be built for you. No
-warnings should appear. If some do, please let the FLTK developer team know via
-the mailing list "fltk.general" or view the bug reporting guidelines at
-https://www.fltk.org/bugs.php
-
-
- 3.5  Testing FLTK
+ 3.4  Testing FLTK
 -------------------
 
 After a successful build, you can test FLTK's capabilities:
 
+  cd build
   test/demo
 
 
- 3.6  Installing FLTK
+ 3.5  Installing FLTK
 ----------------------
 
 If you did not change any of the configuration settings, FLTK will be installed
 in "/usr/local/include" and "/usr/local/lib" by typing
 
-  sudo make install
-
-If you are using the KDE, GNOME or XFCE desktop environments and want to call
-"fluid" from the desktop menu, you will need to install additional files and
-icons under "/usr/share" by typing:
+  sudo cmake --install .
 
-  sudo make install-desktop
+in your build folder. Note the trailing '.' .
 
 It is possible to install FLTK without superuser privileges by changing the
 installation path to a location within the user account by adding the
-"--prefix=PREFIX" parameters to the "./configure" command.
+"-D CMAKE_INSTALL_PREFIX=<path>" parameters to the "cmake" command.
 
 Note: installing FLTK is optional. You can build your own software by using
 the FLTK build tree directly. This is recommended if you link your application
@@ -415,8 +362,8 @@ shared FLTK libraries you may want to install FLTK, particularly on a production
 system.
 
 
- 3.7  Creating new Projects
-----------------------------
+ 3.6  Creating Your Own Projects
+---------------------------------
 
 FLTK provides a neat script named "fltk-config" that can provide all the flags
 needed to build FLTK applications using the same flags that were used to build
@@ -429,14 +376,16 @@ source file is:
 Since version 1.4.0 `fltk-config --compile` can also be used to build a program
 from multiple source files. See the official docs in chapter "FLTK Basics" and
 section "Compiling Multiple Source Files with 'fltk-config'":
-https://www.fltk.org/doc-1.4/basics.html#basics_fltk_config2
+https://www.fltk.org/doc-1.5/basics.html#basics_fltk_config2
 
 "fltk-config" and "fluid" will be installed in "/usr/local/bin/" by default.
 We recommend that you add it to the command search path.
 
+For larger projects than just a few source files we recommend to use CMake.
+Details can be found in README.CMake.txt.
 
 
- 4  Creating a new Project in Code::Blocks
+ 4  Creating a New Project in Code::Blocks
 ===========================================
 
 Code::Blocks is a free and popular C++ IDE in the Linux world. It also runs on