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
After the :can-focus change in the previous commit, widgets
need to set suitable focus and grab_focus implementations
to implement the desired focus behavior.
This commit does that for all widgets.
1. Rename the thing
2. Turn it from a signal to a vfunc
3. Pass the GtkCssStyleChange to it
We don't export any public API about the GtkCssStyleChange yet, it's
just a boring opaque struct.
At the end of GtkImage css validation (during style-updated) when the
css properties (like the icon size) are valid we call _gtk_icon_helper_preload
which does an async icon theme lookup and load. This will happen on a thread
in parallel with the rest of the css machinery, and hopefully by the
time we need the icon it will be ready. If not we will block when we need
it, but during that blocking all the other icons will be loaded.
Testing widget-factory this changes the time of snapshot() from 31 to
25 msec, but on the other hand we also load a few more icons that we
didn't before causing the css validation phase to be about 8 msec slower.
This is because we're preloading all the images in the window, not only
the ones that are visible.
Unfortunately we still load a bunch of icons in snapshot(), from
GtkCssImageIconTheme, and ideally we should try to preload those also.
and gtk_image_set_can_shrink().
Images are meant to always be icon-sized, they can never shrink below
that.
And images are icons, so they are meant to be square. If they are
not, we pretned that's by accident and keep aspect ratio.
This is an automated change doing these command:
git sed -f g gtk_widget_set_has_window gtk_widget_set_has_surface
git sed -f g gtk_widget_get_has_window gtk_widget_get_has_surface
git sed -f g gtk_widget_set_parent_window gtk_widget_set_parent_surface
git sed -f g gtk_widget_get_parent_window gtk_widget_get_parent_surface
git sed -f g gtk_widget_set_window gtk_widget_set_surface
git sed -f g gtk_widget_get_window gtk_widget_get_surface
git sed -f g gtk_widget_register_window gtk_widget_register_surface
git sed -f g gtk_widget_unregister_window gtk_widget_unregister_surface
git checkout NEWS*
That's kinda weird but allows us to delete the texture case from
GtkIconHelper and GTK_IMAGE_TEXTURE from the GtkImageType enum.
And it doesn't cause any other problems because the cell renderer
can't deal with paintables - otherwise it would mirror GtkImage and have
a "paintable" property instead.
If set, the image will draw its contents while keeping their aspect
ratio. That means empty areas show up on the top/bottom or left/right.
Also move the special-case snapshotting code for icons to
GtkIconHelper. That's where it belongs.
This only implements the vfuncs, but does not actually emit signals
yet.
It's also not useed for anything other than snapshot() so far, this
will come in later commits.
Instead of loading them into surfaces (which we want to get rid of), we
load into textures.
In fact, we introduce a new paintable subclass called a GtkScaler that
takes care of tracking scaling.
This also ideally gets rid of an extra conversion once renderers learn
to render textures directly.
Remove all the old 2.x and 3.x version annotations.
GTK+ 4 is a new start, and from the perspective of a
GTK+ 4 developer all these APIs have been around since
the beginning.
