Add rggobi install instructions for os x

README.md

@@ -8,3 +8,22 @@ For a fresh checkout, you'll need to run
 aclocal
 autoconf
 ```
+
+## ggobi/rggobi on OS X
+
+Currently, the easiest way to get rggobi on OS X is to build Gtk2 and ggobi from source using homebrew. This is relatively simple:
+
+```
+# Install homebrew (if you don't already have it)
+ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"
+
+# Install ggobi from source
+brew install ggobi
+brew install libxml2
+
+# Set up PKG_CONFIG_PATH so rggobi can find all the pieces
+PKG_CONFIG_PATH=/usr/local/lib/pkgconfig:/opt/X11/lib/pkgconfig:/usr/local/opt/libxml2/lib/pkgconfig
+
+R
+install.packages("rggobi", type = "source")
+```