To Pd dev -
I just pushed a 'gtk' branch to github for everyone's joy and delectation :) I think this idea was very much annoying to Christof and perhaps others. My strategy is to simplify the tcl commands coming out of Pd to the point that they're easy to parse and carry out in other environments. To start with I'm just using the tcl interpreter but calling gtk drawing commands.
In the future this could be replaced by a more formal API on the Pd side that would conditionally generate either tcl or any other kind of stream to a GUI.
Note that this is only possible because the GUI itself is extremely 'thin', not knowing how to do mouse-hit detection for example. I think this could be viewed as positive (it's fairly easy to just replace it as this branch shows) or as negative ("why can't the GUI take some of the non-real-time work off Pd?)
I'm doing this now because it looks like X windows is being phased out of linux distros and apparently TCL/TK has lots of problems under wayland. It's possible that the TCL/TK folks will somehow patch TCL/TK up to work with Wayland's X emulation in which case this all might be unnecessary - but OTOH I don't mind having an escape route in case not.
AND... the dependence on GTK itself is pretty lightweight so far so this would probably also be adaptable to QT or whatnot if the world so desires. Most of the work is in interpreting the TCL commands (net.c and tclparser.c) which could move right over to some other GUI setup.
cheers Miller