StContainer: Account for floating-point imprecision when sorting actors

When we compare the boxes for two actors, they may appear to overlap
by a small amount because of floating-point imprecision. Allow for
up to 0.1 pixel overlap when determining what children are in the
focus direction from the currently focused actor.

https://bugzilla.gnome.org/show_bug.cgi?id=644134
This commit is contained in:
Owen W. Taylor 2011-03-07 15:31:55 -05:00
parent 43020b20b7
commit c0d0c792e1

View File

@ -445,33 +445,35 @@ filter_by_position (GList *children,
clutter_actor_get_allocation_box (child, &cbox);
/* Filter out children if they are in the wrong direction from
* @rbox, or if they don't overlap it.
* @rbox, or if they don't overlap it. To account for floating-
* point imprecision, an actor is "down" (etc.) from an another
* actor even if it overlaps it by up to 0.1 pixels.
*/
switch (direction)
{
case GTK_DIR_UP:
if (cbox.y2 > rbox->y1)
if (cbox.y2 > rbox->y1 + 0.1)
continue;
if (cbox.x1 >= rbox->x2 || cbox.x2 <= rbox->x1)
continue;
break;
case GTK_DIR_DOWN:
if (cbox.y1 < rbox->y2)
if (cbox.y1 < rbox->y2 - 0.1)
continue;
if (cbox.x1 >= rbox->x2 || cbox.x2 <= rbox->x1)
continue;
break;
case GTK_DIR_LEFT:
if (cbox.x2 > rbox->x1)
if (cbox.x2 > rbox->x1 + 0.1)
continue;
if (cbox.y1 >= rbox->y2 || cbox.y2 <= rbox->y1)
continue;
break;
case GTK_DIR_RIGHT:
if (cbox.x1 < rbox->x2)
if (cbox.x1 < rbox->x2 - 0.1)
continue;
if (cbox.y1 >= rbox->y2 || cbox.y2 <= rbox->y1)
continue;