Add macOS build instructions

README.md

@@ -128,7 +128,73 @@ You'll find your stuff under your MSYS home directory. You can also type `explor
 
 ### macOS (homebrew)
 
-Writing it.
+1. Install [Homebrew](https://brew.sh).
+
+2. Get most of your dependencies from Homebrew:
+
+```sh
+brew install meson cmake automake autoconf sdl2 sdl2_{image,ttf} \
+boost pixman physfs libsigc++ libvorbis fluidsynth pkgconfig
+```
+
+3. Build the rest from source:
+
+```sh
+mkdir ~/src; cd ~/src
+git clone https://github.com/Ancurio/SDL_Sound
+git clone https://github.com/inori-z/ruby --single-branch --branch ruby_1_8_7
+
+cd SDL_Sound && ./bootstrap
+./configure
+make install -j`nproc`
+cd ..
+
+# when you install ruby, some extensions might not want to build.
+# You probably don’t particularly need any, so you can just delete
+# any problematic ones if you like:
+
+rm -rf ruby/ext/tk
+
+# and try building again afterwards. Or you can try to fix whatever
+# the problem is (missing libraries, usually). Hey, do whatever you
+# need to do, Capp’n.
+
+cd ruby && autoconf
+
+# We're putting our build of ruby in its own prefix. macOS already
+# includes Ruby (at least until 10.16 or so), and you really do
+# not want to have any conflicts with it
+
+./configure --prefix=/usr/local/opt/mkxp-ruby --enable-shared --disable-install-doc
+make -j`nproc` && make install
+cd ..
+```
+
+4. Build mkxp-z:
+
+```sh
+git clone https://github.com/inori-z/mkxp-z
+cd mkxp-z
+
+# Ruby 1.8 doesn’t support pkg-config (Might add it in, since this
+# is a bit annoying) so you have to set include and link paths yourself.
+# the header folder that Ruby 1.8 creates for macOS includes a version 
+# number (i.e. `x86_64-darwin18.7.0`), and is going to be located under
+# `/usr/local/opt/mkxp-ruby/lib/ruby/1.8`.
+
+# You will also need to link to `/usr/local/opt/mkxp-ruby/lib`, and tell
+# meson where your pkgconfig path is (`/usr/local/lib/pkgconfig`).
+
+meson build -Dpkg_config_path=/usr/local/lib/pkgconfig \
+-Dcpp_args=-I/usr/local/opt/mkxp-ruby/lib/ruby/1.8/x86_64-darwin18.7.0 \
+-Dcpp_link_args=-L/usr/local/opt/mkxp-ruby/lib
+
+cd build
+ninja
+```
+
+Your results will be in `~/src/mkxp-z/build` . You can type `open ~/src/mkxp-z/build` to get there quickly.
+
 
 ### Linux (Ubuntu)