Native GTK bindings v2

[Artur Skawina]

What's new?

 - Now, in addition to

   GLib, GModule, GObject, Gio, GdkPixbuf, Pango, PangoCairo, PangoFT, Gdk, Atk and Gtk+

   there are also bindings for

   Clutter, ClutterX11, Cogl, CoglPango and Mx.

 - Struct inheritance. No more need for "container.add(&vbox.widget);", you can
   write that as just "container.add(vbox);", the compiler will do all the work
   to check if the 'vbox' is somehow derived from 'widget', and convert the
   pointer by itself.

   This works not only for "struct Widget {}; struct VBox { Widget widget; ... };",
   but also for "struct Widget {}; struct VBox { Widget* widget; ... };".
   You can extend built-in widgets and still use them with the std APIs.

-  Objects can now be constructed as "gtk.VBox(0, 0)";
   the old way, ie "gtk.VBox.new_(0, 0);" still works.

-  All methods that take a (char*) pointer now also silently accept D strings;
   casting to (char*) and/or calling toStringz are no longer necessary. It will
   be done implicitly every time you try to pass a D string; you can still pass
   a (char*) to avoid the copy.

-  GTK (GObject) interfaces supported.

-  Better error messages when registering signal callbacks (the messages given by
   the compiler when a template instantiation fails are not very helpful and, as
   it typically happens via several alias levels, were often just confusing).

-  Some 64-bit fixes (I don't have a 64-bit GTK stack ATM, so there could be
   more problems around).

-  The pre-generated D modules were built using newer library versions
   (still GTK2, only the glib version is newer than that).

-  New examples: Clutter and Mx. Trivial, but enough to get you started.


A D GTK app now looks like this:

   http://repo.or.cz/w/girtod.git/blob/refs/heads/master:/example_gtk.d

doesn't need a single cast (other than for skipping the string copies, using
(void*) library APIs and object lookup tricks, all of which could be avoided, 
but I intentionally didn't do this in the example), looks much better than
the equivalent C version would and couldn't be done any more efficiently in C
(assuming same compiler middle/backend and ignoring the string differences, as
for most cases these don't matter. The convenience makes up for the few extra
copies and these can be avoided in every case where performance really matters).


The code is here: http://repo.or.cz/w/girtod.git

The easiest way to try the bindings is probably to check out the "gtk2" branch,
copy the "gtk2" directory to your app directory and import from there.

The girtod tool used to generate the D modules lives in the "master" branch.
When used with different lib versions than the ones I tried it on, it may need
a few tweaks; sometimes new types appear or move between the libs, new weird or
broken introspection data shows up etc.

artur

PS. Are there any sane Cairo D binding out there? (What's "sane"? Well, if
    there's a "class" in there somewhere then it's not sane)