And replaces its usages in GtkTextView/GtkStyleContext with a hard-coded
0.04 which was the default value for cursor-aspect-ratio. Also remove
the public gtk_draw_insertion_cursor which used draw_insertion_cursor
which in turn looked up cursor-aspect-ratio
And with it, gtk_widget_get_visual() and gtk_widget_set_visual() are
gone.
We now always use the RGBA visual (if available) and otherwise fall back
to the system visual.
This was meant to be silenced unless expicitly requested but
G_ENABLE_DEBUG is defined by default unless --disable-debug is passed to
configure, so use G_ENABLE_CONSISTENCY_CHECKS instead which is only
defined if --enable-debug is explicitly passed.
If somebody decides to use gtk_widget_set_double_buffered() in the
middle of a draw() then there's the risk of calling end_draw_frame()
with an invalid pointer.
Some overeager compilers may warn about the double_buffered bit field
changing values and leading to a potentially uninitialized variable.
In order to avoid compiler warnings or crashes, we can simply store the
value of the double_buffered bit field at the beginning of the rendering
and use that instead of the actual bit field.
https://bugzilla.gnome.org/show_bug.cgi?id=771463
Not all occurrences of this warning can be fixed today, so put it behind
a G_ENABLE_DEBUG flag since it still shows legitimate problems even if
some of them are false positives.
It is important to know whether the returned object can or cannot
change, for a certain widget. For example to connect to the
GtkStyleContext::changed signal.
https://bugzilla.gnome.org/show_bug.cgi?id=769047
Firefox does a bunch of interesting things with GTK.
If the top-level GtkWindow does not have a "csd" style class associated,
Firefox will happily draw the contents of the container used to render
HTML and XUL directly on the top level's GdkWindow; on the other hand,
if a "csd" style class is found, the MozContainer will create a new
child window, and draw on it.
Then, Firefox will proceed to disable double buffering on both the
top-level window and the MozContainer (unless they are backed by the
same GdkWindow, in which case only the top-level will be
single-buffered) *and* it will add a GDK_EXPOSURE_MASK flag to the
MozContainer events for good measure (even if this is only needed for
GTK+ 2.x).
After landing the GdkDrawingContext API in GdkWindow, GTK enabled
automatic double buffering on all top-level windows backed by a native
surface, ad most users of single buffering rely on child widgets instead
of top-levels, and we'd still like to have the same double buffering
behaviour for all top-levels on all backends. Obviously, with Firefox
disabling double buffering on the top-level window, the change broke
their drawing mechanism.
Ideally, Firefox could be fixed to not disable double buffering on the
top-level window when MozContainer has a separate GdkWindow — i.e. the
CSD case — but since we did introduce a slight change of behaviour in
fringe users of the GTK+ API, let's keep backwards compatibility with
the old code for a little while longer, and create an intermediate Cairo
context unbound from the GdkDrawingContext, like we used to do until
GTK+ 3.20.
Instead of associating the GdkWindow that created the GdkDrawingContext
we can directly bind the Cairo context to the GDK drawing context.
Cairo contexts created via gdk_cairo_create() go back to not having a
GdkWindow associated to them, like they did before we introduced the
gdk_window_begin_draw_frame() API.
https://bugzilla.gnome.org/show_bug.cgi?id=766675
Instead of giving out Cairo contexts, GdkWindow should provide a
"drawing context", which can then create Cairo contexts on demand; this
allows us to future proof the API for when we're going to use a
different rendering pipeline, like OpenGL.
https://bugzilla.gnome.org/show_bug.cgi?id=766675
