[pangomm/meson.msvc: 2/2] README.win32: Add instructions on Meson builds

[Chun-wei Fan <fanchunwei src gnome org>]

commit 2604a8ffaeccb7b6e2a50b0a3d8e9ed3587e635c
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Tue Oct 22 14:31:31 2019 +0800

    README.win32: Add instructions on Meson builds
    
    This is added for at least the Visual Studio builds.

 README.win32 | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 61 insertions(+), 4 deletions(-)
---
diff --git a/README.win32 b/README.win32
index 6a662a5..f2203bd 100644
--- a/README.win32
+++ b/README.win32
@@ -27,7 +27,7 @@ that were mentioned above) with mingw by making sure that the mingw
 tools (gcc, ld, dlltool, ..) are called first.
 
 First, make sure that you have working distribution of the native port
-of both libsigc++-2.0.x and gtk+-2.0 on win32 (see
+of both libsigc++-3.x and gtk+-2.0 on win32 (see
 http://www.gimp.org/win32). If you can't compile a simple gtk+ example
 using gcc and `pkg-config --cflags --libs`, you should not even think
 about trying to compile gtkmm, let alone using precompiled libgtkmm
@@ -44,7 +44,7 @@ make
 make check
 make install
 
-2. MS Visual Studio 2017 or later
+2. MS Visual Studio 2017 15.7.0 or later
 
 Open a Visual Studio command prompt suitable for your intended build
 configuration, and change to the MSVC_NMake directory.  Ensure that
@@ -59,11 +59,68 @@ intermediate files that are generated during the build, while an
 'install' target is supported to copy the built DLL and PDB, .lib and
 headers to their appropriate locations under $(PREFIX).
 
-3. Gtkmm methods and signals not available on win32
+3. Using Meson
+
+3.1 Meson with Visual Studio 2017 15.7.0 or later
+
+Note that currently it is not possible to build pangomm directly
+from a GIT checkout with Visual Studio using Meson.
+
+You will need to have Python 3.5.x or later installed with Meson 0.50.0
+or later in order to use this build option, in addition to glibmm,
+cairomm and libsigc++-3.x (built with Visual Studio) and PangoCairo,
+with all of their required dependencies.  The Ninja build tool is
+also required if not using --backend=[vs2017|vs2019] in the Meson
+command line, as noted towards the end of this section.
+
+Open a Visual Studio command prompt and ensure these header files can be
+found in the paths indicated by INCLUDE.  The repetitions below are
+necessary so that we reduce the likelihood that pre-C++-17 versions
+of the headers of glibmm, cairomm and libsigc++ are included, which will
+most likely not work.
+
+-glibmm.h (from glibmm-2.63.x or later)
+-glibmm-2.64\glibmm.h (the *same* glibmm as the previous line)
+-cairomm (from cairomm-1.15.x or later)
+-cairomm-1.16\cairomm.h (the *same* cairomm as the previous line)
+-glibmmconfig.h (from glibmm-2.63.x or later)
+-glibmm-2.64\include\glibmmconfig.h  (the *same* glibmmconfig as the previous line)
+-cairommconfig.h (from cairomm-1.15.x or later)
+-cairomm-1.16\include\cairommconfig.h  (the *same* cairommconfig as the previous line)
+-sigc++\sigc++.h (from libsigc++-3.x or later)
+-sigc++-3.0\sigc++\sigc++.h  (the *same* sigc++\sigc++.h as the previous line)
+-sigc++config.h (from libsigc++-3.x or later)
+-sigc++-3.0\include\sigc++config.h  (the *same* sigc++config.h as the previous line)
+
+Ensure that the import libraries of glibmm, cairomm and libsigc++-3.x
+can be found in the paths indicated by LIB.  Note that Visual Studio
+2019 can use 2017-built libraries without problems; but MSVC builds
+cannot make use of MinGW-built versions of these dependencies.  Note
+that debug builds require debug builds of these dependencies, but
+all other builds, including debugoptimized require release builds
+of these dependencies.
+
+You will need to have a working copy of PangoCairo's pkg-config files,
+which point to the corresponding locations of its headers and .lib's
+and the headers and .lib's of all of its dependencies.
+
+To carry out a build, do this in the same command prompt, with
+the Python interpreter, Meson executable script and Ninja executable
+(if not using --backend=[2017|2019]) in your PATH:
+-Create an empty build directory and cd to it.
+-Run "meson <path-to-pangomm-sources> --buildtype=<buildtype> --prefix=<prefix> [--backend=[2017|2019]]" 
without the quotes.
+-Perform the build using ninja or Visual Studio (if --backend=[2017|2019])
+ is used.  Install the build results after the build succeeds.
+
+3.2 Meson with MinGW
+The standard Meson build instructions for *NIX should work, although it
+is untested at the time of writing.
+
+4. Gtkmm methods and signals not available on win32
 
 All gtkmm methods and signals are available on win32.
 
-4. Gtkmm examples and demos on win32
+5. Gtkmm examples and demos on win32
 
 All demos and examples compile/run on win32