mutter/doc/strut-and-related-updating.txt

55 lines
2.7 KiB
Plaintext
Raw Permalink Normal View History

How updates happen for struts, workareas, and screen/xinerama regions/edges:
One of three things causes meta_window_update_struts to be called
(a) initial window map (window.c:meta_window_new_with_attrs())
(b) update of _net_wm_strut* properties (window.c:process_property_notify())
(c) screen resizes (e.g. via xrandr; from screen.c:meta_screen_resize_func())
meta_window_update_struts (MetaWindow *window)
- Gets new list of struts from window properties
- Makes sure window doesn't single-handedly fill the screen
- records new struts if different and calls invalidate_work_areas()
invalidate_work_areas ()
- Calls meta_workspace_invalidate_work_area() for each workspace it's on
meta_workspace_invalidate_work_area()
- Cleans out all strut lists
- queues all windows for resizing
- Calls meta_screen_queue_workarea_recalc (workspace->screen);
meta_screen_queue_workarea_recalc()
- Adds set_work_area_idle_func() as an idle handler
set_work_area_idle_func()
- Calls set_work_area_hint()
set_work_area_hint()
- Calls meta_workspace_get_work_area_all_xineramas()
- Sets _NET_WORKAREA property
meta_workspace_get_work_area_all_xineramas()
- Calls ensure_work_areas_validated()
ensure_work_areas_validated()
- Loops over xineramas
- Loops over windows, then struts:
- Adds struts to list first time through xinerama loop
- Find the amount of the strut on the given xinerama for <dir>_strut
- Just max the amount of the strut with the all_<dir>_strut
- Makes sure there's a non-empty xinerama workarea
- Record the xinerama workarea
- Make sure there's a non-empty screen workarea
- Record the screen workarea
- Cache the spanning rects for the screen and xinerama regions
- Cache the screen and xinerama edges
Alternatively to all the above, if the idle function for the screen
has not yet fired, constraints.c:setup_constraint_info() can call
either workspace.c:meta_workspace_get_onscreen_region() or
workspace.c:meta_workspace_get_onxinerama_region() which in turn
call workspace.c:ensure_work_areas_validated().
Meaning of related functions that might be difficult to tell apart:
screen.c:meta_screen_get_current_xinerama ()
- Finds out which xinerama the mouse is on with an XQueryPointer
window.c:meta_window_get_work_area_current_xinerama()
window.c:meta_window_get_work_area_for_xinerama()
window.c:meta_window_get_work_area_all_xineramas ()
- All three are for finding the intersection of workareas across
multiple workspaces so that placement of windows can be
determined in such a way that they remain in the workarea for
all workspaces that they are on.