Since gtk+ draws more than the widget and allocates more size to it than
it knows about, this flag doesn't work anymore. Removing it (or setting
it to TRUE for widgets that used to set it to FALSE) fixes drawing
invalidation when these widgets get allocated a new size.
Since setting a clip is mandatory for almost all widgets, we can as well
change the size-allocate signature to include a out_clip parameter, just
like GtkCssGadget did. And since we now always propagate baselines, we
might as well pass that one on to size-allocate.
This way we can also make sure to transform the clip returned from
size-allocate to parent-coordinates, i.e. the same coordinate space
priv->allocation is in.
We now rely on toplevels receiving and forwarding all the events
the windowing should be able to handle. Event masks are no longer a
way to determine whether an event is deliverable ot a widget.
Events will always be delivered in the three captured/target/bubbled
phases, widgets can now just attach GtkEventControllers and let those
handle the events.
gtk_snapshot_pop() => removed
gtk_snapshot_pop_and_append() => gtk_snapshot_pop()
So now there is no way to get a rendernode out of the snapshotting API
until you gtk_snapshot_finish().
Add a new ::measure vfunc similar to GtkCssGadget's that widget
implementations have to override instead of the old get_preferred_width,
get_preferred_height, get_preferred_width_for_height,
get_preferred_height_for_width and
get_preferred_height_and_baseline_for_width.
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.
That would imply the pixelcache monitors the style context for changes
and it doesn't do that.
Its only use case was opacity checks, so add
gtk_pixel_cache_se_is_opaque() instead.
The viewport itself doesn't move, so we cannot use it as the pixel
cache's background. Use the bottommost using element instead, which is
the viewport's child.
This might need adaptations in themes as we want the backgroud to be
opaque to speed up pixel cache performance.
GtkViewport currently tries to draw a background over the bin window.
The feature is a bit broken at the moment, as it does not take into
account padding that might have been set on the GtkViewport, but in
general it does not seem very useful, and goes somewhat against the CSS
box model where every widget/gadget is responsible to draw its own
background. For a fix, we could either have the viewport gain a "bin"
gadget, or we could stop drawing the background.
As it isn't clear that there are any users of this feature, stop drawing
the background; a client can achieve the same effect by drawing the
background on the widget inside the viewport itself.
These days exposure happens only on the native windows (generally the
toplevel window) and is propagated down recursively. The expose event
is only useful for backwards compat, and in fact, for double buffered
widgets we totally ignore the event (and non-double buffering breaks
on wayland).
So, by not setting the mask we avoid emitting these events and then
later ignoring them.
We still keep it on eventbox, fixed and layout as these are used
in weird ways that want backwards compat.
Translate shadow != None into the FRAME style class.
This doesn't change the style classes used for drawing,
it only sets the style class permanently instead of
saving and restoring in draw().
https://bugzilla.gnome.org/show_bug.cgi?id=732256