The function reverses the transform that GTK does before emitting a draw
event. So we can use it in "old" widgets to revert the coordinate system
properly.
This mostly goes to keep consistency with the changes to GtkSizeRequest
in the last patch, as GtkCellSizeRequest requires GtkCellRenderer and
GtkCellRenderer implements GtkCellSizeRequest there's no use in keeping
them separate.
This patch renames the functions:
gtk_cell_size_request_get_request_mode()
=> gtk_cell_renderer_get_request_mode()
gtk_cell_size_request_get_width()
=> gtk_cell_renderer_get_preferred_width()
gtk_cell_size_request_get_height()
=> gtk_cell_renderer_get_preferred_height()
gtk_cell_size_request_get_size()
=> gtk_cell_renderer_get_preferred_size()
gtk_cell_size_request_get_width_for_height()
=> gtk_cell_renderer_get_preferred_width_for_height()
gtk_cell_size_request_get_height_for_width()
=> gtk_cell_renderer_get_preferred_height_for_width()
... and moves the corresponding vfuncs to GtkCellRenderer.
The patch also renames the implementations of these functions in cell
renderers to include the word "preferrred".
It doesn't make sense to keep them separate as GtkSizeRequest requires a
GtkWidget and GtkWidget implements GtkSizeRequest, so you can never have
one without the other.
It also makes the code a lot easier because no casts are required when
calling functions.
Also, the names would translate to gtk_widget_get_width() and people
agreed that this would be a too generic name, so a "preferred" was added
to the names.
So this patch moves the functions:
gtk_size_request_get_request_mode() => gtk_widget_get_request_mode()
gtk_size_request_get_width() => gtk_widget_get_preferred_width()
gtk_size_request_get_height() => gtk_widget_get_preferred_height()
gtk_size_request_get_size() => gtk_widget_get_preferred_size()
gtk_size_request_get_width_for_height() =>
gtk_widget_get_preferred_width_for_height()
gtk_size_request_get_height_for_width() =>
gtk_widget_get_preferred_height_for_width()
... and moves the corresponding vfuncs to the GtkWidgetClass.
The patch also renames the implementations of the vfuncs in widgets to
include the word "preferrred".
The feature can and should be implemented manually using
gdk_window_get_background() and Cairo drawing. A non-cairo drawing API
does not make sense in GDK anymore.
I don't think it's necessary to clear the backing surface when showing
the window, as we're going to repaint it anyway. If it's needed, we can
implement it again using internal APIs, as the public window_clear()
APIs are going away.
Previously, we tried to move the context's origin to the widget's top
left location, no matter what window the paint was happening on. Now we
only do that for child windows of the widget's window and leave the
context untouched for windows that the widget has created outside its
own hierarchy. In those casses, we also don't clip the context to
the widget's allocation.
Includes fixes to GtkHandlebox for this effect and fixes all known
issues with it.
These semantics assume that gtk_widget_draw() should only draw the parts
of a widget that are inside child windows and not draw stuff that is
located in completely different GdkWindows. In the handlebox case, it
means that it should only draw the handle when it is attached, but not
when it isn't. We'll likely need a special draw function for the
detached handlebox if we want to draw it.
I've seen (and written) quite some widgets (and theme engines) that use
cairo_paint() to draw the background. So avoiding overdraw makes sense.
Also move all that setup into a _gtk_widget_draw_internal() function
that will be used by all functions that can be used by other functions
that draw widgets.
