This commit hides GdkDragContext and GdkDragContextClass, adds
vfuncs for most drag context functionality, and turns the X11 DND
implementation into GdkDragContextX11. We also add vfuncs to
GdkDisplay for gdk_drag_get_protocol and to GdkWindow for
gdk_drag_begin, and implemenet them for X11.
Other backends need similar treatment and are broken now.
One less magic function. Also refactored it to make it easier to
implement. It now returns TRUE if it beeped and FALSE if it failed to do
so. A default implementation exists that just returns FALSE for all the
backends that can't beep windows (read: everything but X11 with XKB -
and why on earth do keyboard libs implement beeping?)
Trying to get rid of all the _gdk_windowing_something() functions that
we expect backends to magically know about and instead put them in a
proper interface (mostly GdkWindowImplClass).
Since what we are doing is turning an icon with alpha into a
no-alpha icon + mask for legacy window managers, it makes more sense
to use the system visual than the window's visual, which might
be ARGB.
https://bugzilla.gnome.org/show_bug.cgi?id=634821
In this case, gnome-terminal sets an RGBA visual on its window,
and we need to be careful when creating the icon pixmap, to create
the pixmap with the same depth as the visual, or we risk a BadMatch
from XRenderCreatePicture deep inside cairo.
In particular, the following functions are gone:
- gdk_screen_get_default_colormap()
- gdk_screen_set_default_colormap()
- gdk_screen_get_system_colormap()
- gdk_screen_get_rgba_colormap()
This way, we can specify a colormap when constructing windows. And ew
must do that to avoid BadMatch from XCreateWindow when we use a
different visual.
Also add a priv pointer to GdkVisual and use it for the GdkVisualPrivate
structure. Then Make GdkVisualPrivate actually private to
gdkvisual-x11.c and make other callers use proper function calls to
access it.
Direct and TrueColor visuals don't alloc colors, so they don't need to
fiddle with colormaps. Just copy the code that computes the pixel value
from gdkcolor-x11.c and use it. For other visual types, don't set the
background color and fallback to background = None.
No more GdkPixmap to store the icon and its mask, but instead use cairo
surfaces. Also render the icon into the surfaces using Cairo instead of
gdk_pixbuf_render_threshold_alpha().
Now the window background is a cairo_pattern_t. The backends will try to
set this as good as they can on the windowing system, but no guarantees
are made on wether the windowing system supports the pattern.
Also gets rid of GDK_NO_BG as undefined behavior is not a good idea to
support, and GDK_NO_BG effectively made the window's contents undefined.
It wasn't effectively used in GTK anyway.
