[meson] Fix dependency lookup and generate `ftconfig.h`.
- zlib: If not found on the system, meson can build it as a
subproject. We thus never use the (outdated) zlib support that
comes with FreeType. Doing so has the additional advantage that
the zlib code can be shared with other projects like GLib if both
are subprojects of an application.
- harfbuzz: Build as a subproject if not found on the system.
- 'QUESTION: What if the compiler doesn't support `-D` but uses `/D`
instead as on Windows?' Answer: Meson translate arguments for us.
- visibility: Replace self-made code with meson-specific solution.
* meson.build (ft2_defines): Rewrite logic to set and handle it.
(process_header_command): New variable, previously called
`ftoption_command`.
(ftoption_command, ftconfig_command): New variables.
(zlib_option): Removed.
(zlib_dep): New variable.
(ft2_deps): Updated.
(harfbuzz_dep): Updated.
(ftconfig_h_in, ftconfig_h): New variables.
(ft2_sources): Updated.
(ft2_lib): Updated, handle visibility.
(summary): Updted.
* meson_options.txt (zlib): Updated.
Example usage:
# Configure Meson build in directory `build-meson` to generate
# release binaries comparable to to the ones from the
# autotools/make build system.
meson setup build-meson \
--prefix=/usr/local \
--buildtype=debugoptimized \
--strip \
-Db_ndebug=true
# After configuring the Meson build with the above command,
# compile and install to `/usr/local/`; this includes a pkg-config
# file.
ninja -C build-meson install
# Alternatively, compile and install to `/tmp/aa/usr/local/...`
# for packaging.
DESTDIR=/tmp/aa ninja -C build-meson install
# Generate documentation under `build-meson/docs`.
ninja -C build-meson docs
Library size comparison for stripped `libfreetype.so` generated by
all three build systems:
- Default build (autotools + libtool): 712 KiB
- CMake build (RelWithDebInfo): 712 KiB
- Meson build: 712 KiB
* meson.build: New top-level Meson build file for the library.
* meson_options.txt: New file. It holds user-selectable options for
the build, which can be printed with `meson configure`, and selected
at `meson setup` or `meson --reconfigure` time with
`-D<option>=<value>`.
* scripts/parse_modules_cfg.py: A script invoked by `meson.build` to
parse `modules.cfg` and extract important information out of it
(i.e., the list of modules).
* scripts/process_ftoption_h.py: New script invoked by `meson.build`
to process the original `ftoption.h` file. It enables or disables
configuration macro variables based on the available dependencies.
This is similar to what other build systems are using (i.e., Meson's
`configure_file()` command is not used here).
* scripts/extract_freetype_version.py: New script invoked by
`meson.build` to extract the FreeType version number from
`<freetype/freetype.h>`.
* scripts/extract_libtool_version.py: New script invoked by
`meson.build` to extract the libtool `revision_info` data from
`builds/unix/configure.raw`, and to generate the corresponding
shared library suffix.
* scripts/generate_reference_docs.py: New script invoked by
`meson.build` to generate the FreeType 2 reference documentation
(using the `docwriter` and `mkdocs` packages, which must be already
installed).
