Mention that it's safe to use <cell-packing> tag for any GtkCellLayout
in GTK+ since they *all* use an underlying GtkCellArea (at least they
will once the other branches land).
I have never really liked the updates done to the adjustments in
do_validate_rows() and other validation functions. But it is really
required. I have to come up with a real solution to this one day.
This fixes a GTK+ 3.0 regression. In GTK+ 2, the render method
on GtkCellRenderer had a expose_area parameter, typically set to
cell_area. This parameter was used for clipping cell content to be
rendered to the cell area (and thus clipping to within the focus
rectangle). During the rendering clean up this parameter was removed
and no clipping put back into place.
Since expose_area was usually equal to cell_area anyway, it does not make
sense to reintroduce the expose_area parameter. Instead, we do clipping at
two levels:
- in gtk_cell_renderer_render() we clip to background_area. We cannot
clip to cell_area here because we want to allow cell renderers to
render in the background area (e.g. background color/effect).
- cell renderers should clip to clip_area when rendering cell
content individually (as they had to individually clip to expose_region
before).
Check (x, y) is inside background area. If yes, continue processing
and clamp the coordinates into cell area. This way we will properly
handle getting a cell (which is only used for setting the focus cell)
for clicks in the indentation area (in LTR and RTL mode) and clicks
in the focus rectangle area in case focus-line-width is large.
The cell's focus rectangle is located around the cell's aligned area.
To get to the correct coordinates for this rectangle, we have to subtract
focus_line_width from the found aligned_area.
Size requests should only ever need to return the screen's width/height
and max. This way, potentially large widgets (tree view or icon view)
don't need to do so many computations, but can stop when their computed
size has reached the screen size.
