Using gtk_widget_insert_before on a complex container
is a *bad* idea; it will mess up the containers bookkeeping
of its children and can easily lead to failure and crashes.
My previous change here was too hasty - this code is not
actually transforming points - it is just a convoluted
way to transform the z axis from child coordinates to
the parent.
Replace our uses of graphene_matrix_transform_point,
_point3d and _bounds by our own versions that handle
projective transforms correctly.
This fixes render node bounds being incorrect for widgets
involving projective transforms (e.g. testrevealer swing
transformations), and also fixes picking on such widgets.
The code in gtk_widget_real_css_changed assumes that
queue_resize > queue_allocate > queue_draw, but the
second one is not really true. These days, we happily
keep reusing the same render node even when the child
allocation is changed.
So, if a css change has flags that tell us we should
redraw, we need to queue a draw, otherwise we might
end up reusing an outdated render node.
This fixes spinners staying visible when they stop
spinning, despite the theme setting their opacity
to 0.
Make GdkEvents hold a single GdkDevice. This device is closer to
the logical device conceptually, although it must be sufficient for
device checks (i.e. GdkInputSource), which makes it similar to the
physical devices.
Make the logical devices have a more accurate GdkInputSource where
needed, and conflate the event devices altogether.
Some widgets have different roles after they are constructed, so we need
to allow changing the role defined by the class. We should still avoid
setting a role after the GtkATContext has been created.
Some widgets have different accessible roles depending on some
parameter, so we cannot set the role at class init time. For those
widgets, we add an "accessible-role" property to GtkAccessible, and we
allow setting it (only) at construction time.
Each widget type has an accessible role associated to its class, as
roles cannot change during the life time of a widget instance.
Each widget is also responsible for creating an ATContext, to proxy
state changes to the underlying accessibility infrastructure.
GtkAccessible is an interface for accessible UI elements.
Currently, it doesn't do much except exist as a type; in the future, it
will be the entry point for all accessible state in GTK.
To build a better world sometimes means having to tear the old one down.
-- Alexander Pierce, "Captain America: The Winter Soldier"
ATK served us well for nearly 20 years, but the world has changed, and
GTK has changed with it. Now ATK is mostly a hindrance towards improving
the accessibility stack:
- it maps to a very specific implementation, AT-SPI, which is Linux and
Unix specific
- it requires implementing the same functionality in three different
layers of the stack: AT-SPI, ATK, and GTK
- only GTK uses it; every other Linux and Unix toolkit and application
talks to AT-SPI directly, including assistive technologies
Sadly, we cannot incrementally port GTK to a new accessibility stack;
since ATK insulates us entirely from the underlying implementation, we
cannot replace it piecemeal. Instead, we're going to remove everything
and then incrementally build on a clean slate:
- add an "accessible" interface, implemented by GTK objects directly,
which describe the accessible role and state changes for every UI
element
- add an "assistive technology context" to proxy a native accessibility
API, and assign it to every widget
- implement the AT context depending on the platform
For more information, see: https://gitlab.gnome.org/GNOME/gtk/-/issues/2833
This got stuck in ancient times when widgets were windowed, so the devices
in a window to know the devices in that widget would pan out. We do only
want here the devices that are inside the widget, not spread over the
surface, so rewrite this helper function to poke the toplevel foci, and
look they are contained inside the widget.
