/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/*
* Copyright (C) 2001 Havoc Pennington
* Copyright (C) 2005 Elijah Newren
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef META_STACK_H
#define META_STACK_H
/**
* SECTION:stack
* @short_description: Which windows cover which other windows
*
* There are two factors that determine window position.
*
* One is window->stack_position, which is a unique integer
* indicating how windows are ordered with respect to one
* another. The ordering here transcends layers; it isn't changed
* as the window is moved among layers. This allows us to move several
* windows from one layer to another, while preserving the relative
* order of the moved windows. Also, it allows us to restore
* the stacking order from a saved session.
*
* However when actually stacking windows on the screen, the
* layer overrides the stack_position; windows are first sorted
* by layer, then by stack_position within each layer.
*/
#include "core/display-private.h"
/**
* A sorted list of windows bearing some level of resemblance to the stack of
* windows on the X server.
*
* (This is only used as a field within a MetaScreen; we treat it as a separate
* class for simplicity.)
*/
struct _MetaStack
{
GObject parent;
/** The MetaDisplay containing this stack. */
MetaDisplay *display;
/** The MetaWindows of the windows we manage, sorted in order. */
GList *sorted;
/**
* If this is zero, the local stack oughtn't to be brought up to date with
* the X server's stack, because it is in the middle of being updated.
* If it is positive, the local stack is said to be "frozen", and will need
* to be thawed that many times before the stack can be brought up to date
* again. You may freeze the stack with meta_stack_freeze() and thaw it
* with meta_stack_thaw().
*/
int freeze_count;
/**
* The last-known stack of all windows, bottom to top. We cache it here
* so that subsequent times we'll be able to do incremental moves.
*/
GArray *last_all_root_children_stacked;
/**
* Number of stack positions; same as the length of added, but
* kept for quick reference.
*/
gint n_positions;
/** Is the stack in need of re-sorting? */
unsigned int need_resort : 1;
/**
* Are the windows in the stack in need of having their
* layers recalculated?
*/
unsigned int need_relayer : 1;
/**
* Are the windows in the stack in need of having their positions
* recalculated with respect to transiency (parent and child windows)?
*/
unsigned int need_constrain : 1;
};
#define META_TYPE_STACK (meta_stack_get_type ())
G_DECLARE_FINAL_TYPE (MetaStack, meta_stack, META, STACK, GObject)
/**
* meta_stack_new:
* @display: The MetaDisplay which will be the parent of this stack.
*
* Creates and initialises a MetaStack.
*
* Returns: The new stack.
*/
MetaStack * meta_stack_new (MetaDisplay *display);
/**
* meta_stack_add:
* @stack: The stack to add it to
* @window: The window to add
*
* Adds a window to the local stack. It is a fatal error to call this
* function on a window which already exists on the stack of any screen.
*/
void meta_stack_add (MetaStack *stack,
MetaWindow *window);
/**
* meta_stack_remove:
* @stack: The stack to remove it from
* @window: The window to remove
*
* Removes a window from the local stack. It is a fatal error to call this
* function on a window which exists on the stack of any screen.
*/
void meta_stack_remove (MetaStack *stack,
MetaWindow *window);
/**
* meta_stack_update_layer:
* @stack: The stack to recalculate
* @window: Dummy parameter
*
* Recalculates the correct layer for all windows in the stack,
* and moves them about accordingly.
*
*/
void meta_stack_update_layer (MetaStack *stack,
MetaWindow *window);
/**
* meta_stack_update_transient:
* @stack: The stack to recalculate
* @window: Dummy parameter
*
* Recalculates the correct stacking order for all windows in the stack
* according to their transience, and moves them about accordingly.
*
* FIXME: What's with the dummy parameter?
*/
void meta_stack_update_transient (MetaStack *stack,
MetaWindow *window);
/**
* meta_stack_raise:
* @stack: The stack to modify.
* @window: The window that's making an ascension.
* (Amulet of Yendor not required.)
*
* Move a window to the top of its layer.
*/
void meta_stack_raise (MetaStack *stack,
MetaWindow *window);
/**
* meta_stack_lower:
* @stack: The stack to modify.
* @window: The window that's on the way downwards.
*
* Move a window to the bottom of its layer.
*/
void meta_stack_lower (MetaStack *stack,
MetaWindow *window);
/**
* meta_stack_freeze:
* @stack: The stack to freeze.
*
* Prevent syncing to server until the next call of meta_stack_thaw(),
* so that we can carry out multiple operations in one go without having
* everything halfway reflected on the X server.
*
* (Calls to meta_stack_freeze() nest, so that multiple calls to
* meta_stack_freeze will require multiple calls to meta_stack_thaw().)
*/
void meta_stack_freeze (MetaStack *stack);
/**
* meta_stack_thaw:
* @stack: The stack to thaw.
*
* Undoes a meta_stack_freeze(), and processes anything which has become
* necessary during the freeze. It is an error to call this function if
* the stack has not been frozen.
*/
void meta_stack_thaw (MetaStack *stack);
/**
* meta_stack_get_top:
* @stack: The stack to examine.
*
* Finds the top window on the stack.
*
* Returns: The top window on the stack, or %NULL in the vanishingly unlikely
* event that you have no windows on your screen whatsoever.
*/
MetaWindow * meta_stack_get_top (MetaStack *stack);
/**
* meta_stack_get_bottom:
* @stack: The stack to search
*
* Finds the window at the bottom of the stack. Since that's pretty much
* always the desktop, this isn't the most useful of functions, and nobody
* actually calls it. We should probably get rid of it.
*/
MetaWindow * meta_stack_get_bottom (MetaStack *stack);
/**
* meta_stack_get_above:
* @stack: The stack to search.
* @window: The window to look above.
* @only_within_layer: If %TRUE, will return %NULL if @window is the
* top window in its layer.
*
* Finds the window above a given window in the stack.
* It is not an error to pass in a window which does not exist in
* the stack; the function will merely return %NULL.
*
* Returns: %NULL if there is no such window;
* the window above @window otherwise.
*/
MetaWindow * meta_stack_get_above (MetaStack *stack,
MetaWindow *window,
gboolean only_within_layer);
/**
* meta_stack_get_below:
* @stack: The stack to search.
* @window: The window to look below.
* @only_within_layer: If %TRUE, will return %NULL if window is the
* bottom window in its layer.
*
* Finds the window below a given window in the stack.
* It is not an error to pass in a window which does not exist in
* the stack; the function will merely return %NULL.
*
*
* Returns: %NULL if there is no such window;
* the window below @window otherwise.
*/
MetaWindow * meta_stack_get_below (MetaStack *stack,
MetaWindow *window,
gboolean only_within_layer);
/**
* meta_stack_list_windows:
* @stack: The stack to examine.
* @workspace: If not %NULL, only windows on this workspace will be
* returned; otherwise all windows in the stack will be
* returned.
*
* Finds all the windows in the stack, in order.
*
* Returns: (transfer container) (element-type Meta.Window):
* A list of windows, in stacking order, honouring layers.
*/
GList * meta_stack_list_windows (MetaStack *stack,
MetaWorkspace *workspace);
/**
* meta_stack_windows_cmp:
* @stack: A stack containing both window_a and window_b
* @window_a: A window
* @window_b Another window
*
* Comparison function for windows within a stack. This is not directly
* suitable for use within a standard comparison routine, because it takes
* an extra parameter; you will need to wrap it.
*
* (FIXME: We could remove the stack parameter and use the stack of
* the screen of window A, and complain if the stack of the screen of
* window B differed; then this would be a usable general comparison function.)
*
* (FIXME: Apparently identical to compare_window_position(). Merge them.)
*
* \return -1 if window_a is below window_b, honouring layers; 1 if it's
* above it; 0 if you passed in the same window twice!
*/
int meta_stack_windows_cmp (MetaStack *stack,
MetaWindow *window_a,
MetaWindow *window_b);
/**
* meta_window_set_stack_position:
* @window: The window which is moving.
* @position: Where it should move to (0 is the bottom).
*
* Sets the position of a window within the stack. This will only move it
* up or down within its layer. It is an error to attempt to move this
* below position zero or above the last position in the stack (however, since
* we don't provide a simple way to tell the number of windows in the stack,
* this requirement may not be easy to fulfil).
*/
void meta_window_set_stack_position (MetaWindow *window,
int position);
/**
* meta_stack_get_positions:
* @stack: The stack to examine.
*
* Returns the current stack state, allowing rudimentary transactions.
*
* Returns: (transfer container) (element-type Meta.Window):
* An opaque #GList representing the current stack sort order;
* it is the caller's responsibility to free it.
* Pass this to meta_stack_set_positions() later if you want to restore
* the state to where it was when you called this function.
*/
GList * meta_stack_get_positions (MetaStack *stack);
/**
* meta_stack_set_positions:
* @stack: The stack to roll back.
* @windows: The list returned from meta_stack_get_positions().
*
* Rolls back a transaction, given the list returned from
* meta_stack_get_positions().
*
*/
void meta_stack_set_positions (MetaStack *stack,
GList *windows);
void meta_stack_update_window_tile_matches (MetaStack *stack,
MetaWorkspace *workspace);
#endif