I was compiling GTK+ 3.12 today, and while asking about some compilation related errors on #gtk+ channel I got in the conversation with the developers there.
They advised me to not port drgeo to the latest version of gtk+ as “gtk is a moving target”. They said to only do that if I want something that is not yet available with the previous versions.
So instead I’ll port the software to the Gtk+3 version that are distributed with the distros.
Will start with the preparation stuff to begin migrating.