This modifies the size machinery in order to allow baseline support.
We add a new widget vfunc get_preferred_height_and_baseline_for_width
which queries the normal height_for_width (or non-for-width if width
is -1) and additionally returns optional (-1 means "no baseline")
baselines for the minimal and natural heights.
We also add a new gtk_widget_size_allocate_with_baseline() which
baseline-aware containers can use to allocate children with a specific
baseline, either one inherited from the parent, or one introduced due
to requested baseline alignment in the container
itself. size_allocate_with_baseline() works just like a normal size
allocation, except the baseline gets recorded so that the child can
access it via gtk_widget_get_allocated_baseline() when it aligns
itself.
There are also adjust_baseline_request/allocation similar to the
allocation adjustment, and we extend the size request cache to also
store the baselines.
We need to disconnect the frame clock when we unrealize (at which
point the old clock is still alive) not in destroy(). Since there
is no common unrealize for containers, trigger this from GtkWidget.
Instead of having gdk_frame_clock_request_frame() have
gdk_frame_clock_request_phase() where we can say what phase we need.
This allows us to know if we get a frame-request during layout whether
it's just a request for drawing from the layout, or whether another
layout phase is needed.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
Instead of using 1 global queue for both resizes and style validation,
use 2 queues. This makes the code a lot simpler and fixes a bug where we
could accidentally stop restylying for very delayed restyles.
Add an internal API that allows GtkStyleContext to create a widget path
for the widget and with that bypassing gtk_widget_get_path() and that
function caching the path.
Include the child widget path in the returned path now. This allows
customizing the path of the current widgets - like adding flags to child
widgets (and maybe siblings in the future).
This commit simply removes some child->parent == container checks,
to add some flexibility for containers with 'inner structure'.
If these checks are considered useful, we can bring them back
with a is_child vfunc that allows container implementations to
decided who they consider legitimate child.
This is a variant of gtk_widget_child_notify() that takes an
explicit container, instead of relying on widget->parent to
be the correct container to use.
The constant size request mode defines a request mode where
height-for-width geometry is unneeded, thus optimizing GTK+
by reducing the overall amount of requests that need to be
performed and cached while resizing an interface.
Requires fixes to GtkContainer and GtkWindow to unmap their
children, rather than just withdrawing or hiding the container
window.
Requires fix to GtkHandleBox to chain up to GtkContainer unmap.
Historically we avoided these unmaps for efficiency reasons,
but these days it's a bigger problem that there's no way
for child widgets to know that one of their ancestors has
become unmapped.
This allows us to add a check before executing
->get_preferred_height_for_width() to ensure we always
request for at least the minimum required size (and lets
us remove the warning in gtkcontainer.c telling implementors
to do this check manually from thier container implementations).
