This library is meant to be the new CSS library that gets used from GDK,
GSK and GTK for string printing and parsing.
As a first step, move GtkCssProviderError into it.
While doing so, split it into GtkCssParserError (for critical problems)
and GtkCssParserWarning (for non-critical problems).
The need of a specialised fixed layout container that can be placed into
a GtkScrolledWindow ceased to exist once GtkScrolledWindow gained the
ability to automatically interpose a GtkViewport when adding a child
that does not implement GtkScrollable.
All the other justifications that led to the existence of GtkLayout as a
separate widget from GtkFixed have been largely made irrelevant in the
20 years since its inception.
...and the setter/getter for it.
This is a very old X session management thing, and you
will be hard-pressed to find a session manager that can
make use of it, and even harder-pressed to find apps
using it to their advantage.
Layout managers needs a way to store properties that control the layout
policy of a widget; typically, we used to store these in GtkContainer's
child properties, but since GtkLayoutManager is decoupled from the
actual container widget, we need a separate storage. Additionally, child
properties have their own downsides, like requiring a separate, global
GParamSpecPool storage, and additional lookup API.
GtkLayoutChild is a simple GObject class, which means you can introspect
and document it as you would any other type.
We delegate the size request mode, the measuring, and the allocation of
a widget through a GtkLayoutManager instance, if one has been attached
to the widget; otherwise, we fall back to the widget's own implementation.
A base abstract class for layout manager delegate objects.
Layout managers are associated to a single widget, like event
controllers, and are responsible for measuring and allocating the
children of the widget they are bound to.
Add a ::show-peek-icon property and show a clickable
icon when it is set. Clicking it toggles the visibility
of the content. The same functionality is also accessible
via a context menu item.
This is a common feature of password entries.
Instead of gtk_snapshot_offset(), provide a full set of functions
kept in sync with GtkTransform APIs.
On top of that, add gtk_snapshot_save() and gtk_snapshot_restore()
mirroring cairo_save()/restore() that allow saving a snapshot's
transform state.
This is a new object (well, boxed type, but I'm calling it object) for
dealing with transform in a more constructive way than graphene_matrix_t
by keeping track of how the transform was created.
This way, reasoning about the transform becomes easier, and we can create
better ways to print it or transition from one transform to another one.
An example of this is that while a 0 degree and a 360degree rotation are
both the identity matrix, doing a transition between the two would cause
a rotation.
