mutter/src/core/edge-resistance.c
2014-05-02 09:34:48 -04:00

1268 lines
44 KiB
C

/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/* Edge resistance for move/resize operations */
/*
* Copyright (C) 2005, 2006 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/>.
*/
#include <config.h>
#include "edge-resistance.h"
#include "boxes-private.h"
#include "display-private.h"
#include "workspace-private.h"
/* A simple macro for whether a given window's edges are potentially
* relevant for resistance/snapping during a move/resize operation
*/
#define WINDOW_EDGES_RELEVANT(window, display) \
meta_window_should_be_showing (window) && \
window != display->grab_window && \
window->type != META_WINDOW_DESKTOP && \
window->type != META_WINDOW_MENU && \
window->type != META_WINDOW_SPLASHSCREEN
struct ResistanceDataForAnEdge
{
gboolean timeout_setup;
guint timeout_id;
int timeout_edge_pos;
gboolean timeout_over;
GSourceFunc timeout_func;
MetaWindow *window;
int keyboard_buildup;
};
typedef struct ResistanceDataForAnEdge ResistanceDataForAnEdge;
struct MetaEdgeResistanceData
{
GArray *left_edges;
GArray *right_edges;
GArray *top_edges;
GArray *bottom_edges;
ResistanceDataForAnEdge left_data;
ResistanceDataForAnEdge right_data;
ResistanceDataForAnEdge top_data;
ResistanceDataForAnEdge bottom_data;
};
static void compute_resistance_and_snapping_edges (MetaDisplay *display);
/* !WARNING!: this function can return invalid indices (namely, either -1 or
* edges->len); this is by design, but you need to remember this.
*/
static int
find_index_of_edge_near_position (const GArray *edges,
int position,
gboolean want_interval_min,
gboolean horizontal)
{
/* This is basically like a binary search, except that we're trying to
* find a range instead of an exact value. So, if we have in our array
* Value: 3 27 316 316 316 505 522 800 1213
* Index: 0 1 2 3 4 5 6 7 8
* and we call this function with position=500 & want_interval_min=TRUE
* then we should get 5 (because 505 is the first value bigger than 500).
* If we call this function with position=805 and want_interval_min=FALSE
* then we should get 7 (because 800 is the last value smaller than 800).
* A couple more, to make things clear:
* position want_interval_min correct_answer
* 316 TRUE 2
* 316 FALSE 4
* 2 FALSE -1
* 2000 TRUE 9
*/
int low, high, mid;
int compare;
MetaEdge *edge;
/* Initialize mid, edge, & compare in the off change that the array only
* has one element.
*/
mid = 0;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
/* Begin the search... */
low = 0;
high = edges->len - 1;
while (low < high)
{
mid = low + (high - low)/2;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
if (compare == position)
break;
if (compare > position)
high = mid - 1;
else
low = mid + 1;
}
/* mid should now be _really_ close to the index we want, so we start
* linearly searching. However, note that we don't know if mid is less
* than or greater than what we need and it's possible that there are
* several equal values equal to what we were searching for and we ended
* up in the middle of them instead of at the end. So we may need to
* move mid multiple locations over.
*/
if (want_interval_min)
{
while (compare >= position && mid > 0)
{
mid--;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
}
while (compare < position && mid < (int)edges->len - 1)
{
mid++;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
}
/* Special case for no values in array big enough */
if (compare < position)
return edges->len;
/* Return the found value */
return mid;
}
else
{
while (compare <= position && mid < (int)edges->len - 1)
{
mid++;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
}
while (compare > position && mid > 0)
{
mid--;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
}
/* Special case for no values in array small enough */
if (compare > position)
return -1;
/* Return the found value */
return mid;
}
}
static gboolean
points_on_same_side (int ref, int pt1, int pt2)
{
return (pt1 - ref) * (pt2 - ref) > 0;
}
static int
find_nearest_position (const GArray *edges,
int position,
int old_position,
const MetaRectangle *new_rect,
gboolean horizontal,
gboolean only_forward)
{
/* This is basically just a binary search except that we're looking
* for the value closest to position, rather than finding that
* actual value. Also, we ignore any edges that aren't relevant
* given the horizontal/vertical position of new_rect.
*/
int low, high, mid;
int compare;
MetaEdge *edge;
int best, best_dist, i;
gboolean edges_align;
/* Initialize mid, edge, & compare in the off change that the array only
* has one element.
*/
mid = 0;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
/* Begin the search... */
low = 0;
high = edges->len - 1;
while (low < high)
{
mid = low + (high - low)/2;
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
if (compare == position)
break;
if (compare > position)
high = mid - 1;
else
low = mid + 1;
}
/* mid should now be _really_ close to the index we want, so we
* start searching nearby for something that overlaps and is closer
* than the original position.
*/
best = old_position;
best_dist = INT_MAX;
/* Start the search at mid */
edge = g_array_index (edges, MetaEdge*, mid);
compare = horizontal ? edge->rect.x : edge->rect.y;
edges_align = meta_rectangle_edge_aligns (new_rect, edge);
if (edges_align &&
(!only_forward || !points_on_same_side (position, compare, old_position)))
{
int dist = ABS (compare - position);
if (dist < best_dist)
{
best = compare;
best_dist = dist;
}
}
/* Now start searching higher than mid */
for (i = mid + 1; i < (int)edges->len; i++)
{
edge = g_array_index (edges, MetaEdge*, i);
compare = horizontal ? edge->rect.x : edge->rect.y;
edges_align = horizontal ?
meta_rectangle_vert_overlap (&edge->rect, new_rect) :
meta_rectangle_horiz_overlap (&edge->rect, new_rect);
if (edges_align &&
(!only_forward ||
!points_on_same_side (position, compare, old_position)))
{
int dist = ABS (compare - position);
if (dist < best_dist)
{
best = compare;
best_dist = dist;
}
break;
}
}
/* Now start searching lower than mid */
for (i = mid-1; i >= 0; i--)
{
edge = g_array_index (edges, MetaEdge*, i);
compare = horizontal ? edge->rect.x : edge->rect.y;
edges_align = horizontal ?
meta_rectangle_vert_overlap (&edge->rect, new_rect) :
meta_rectangle_horiz_overlap (&edge->rect, new_rect);
if (edges_align &&
(!only_forward ||
!points_on_same_side (position, compare, old_position)))
{
int dist = ABS (compare - position);
if (dist < best_dist)
{
best = compare;
best_dist = dist;
}
break;
}
}
/* Return the best one found */
return best;
}
static gboolean
movement_towards_edge (MetaSide side, int increment)
{
switch (side)
{
case META_SIDE_LEFT:
case META_SIDE_TOP:
return increment < 0;
case META_SIDE_RIGHT:
case META_SIDE_BOTTOM:
return increment > 0;
default:
g_assert_not_reached ();
}
}
static gboolean
edge_resistance_timeout (gpointer data)
{
ResistanceDataForAnEdge *resistance_data = data;
resistance_data->timeout_over = TRUE;
resistance_data->timeout_id = 0;
(*resistance_data->timeout_func)(resistance_data->window);
return FALSE;
}
static int
apply_edge_resistance (MetaWindow *window,
int old_pos,
int new_pos,
const MetaRectangle *old_rect,
const MetaRectangle *new_rect,
GArray *edges,
ResistanceDataForAnEdge *resistance_data,
GSourceFunc timeout_func,
gboolean xdir,
gboolean keyboard_op)
{
int i, begin, end;
int last_edge;
gboolean increasing = new_pos > old_pos;
int increment = increasing ? 1 : -1;
const int PIXEL_DISTANCE_THRESHOLD_TOWARDS_WINDOW = 16;
const int PIXEL_DISTANCE_THRESHOLD_AWAYFROM_WINDOW = 0;
const int PIXEL_DISTANCE_THRESHOLD_TOWARDS_MONITOR = 32;
const int PIXEL_DISTANCE_THRESHOLD_AWAYFROM_MONITOR = 0;
const int PIXEL_DISTANCE_THRESHOLD_TOWARDS_SCREEN = 32;
const int PIXEL_DISTANCE_THRESHOLD_AWAYFROM_SCREEN = 0;
const int TIMEOUT_RESISTANCE_LENGTH_MS_WINDOW = 0;
const int TIMEOUT_RESISTANCE_LENGTH_MS_MONITOR = 0;
const int TIMEOUT_RESISTANCE_LENGTH_MS_SCREEN = 0;
/* Quit if no movement was specified */
if (old_pos == new_pos)
return new_pos;
/* Remove the old timeout if it's no longer relevant */
if (resistance_data->timeout_setup &&
((resistance_data->timeout_edge_pos > old_pos &&
resistance_data->timeout_edge_pos > new_pos) ||
(resistance_data->timeout_edge_pos < old_pos &&
resistance_data->timeout_edge_pos < new_pos)))
{
resistance_data->timeout_setup = FALSE;
if (resistance_data->timeout_id != 0)
{
g_source_remove (resistance_data->timeout_id);
resistance_data->timeout_id = 0;
}
}
/* Get the range of indices in the edge array that we move past/to. */
begin = find_index_of_edge_near_position (edges, old_pos, increasing, xdir);
end = find_index_of_edge_near_position (edges, new_pos, !increasing, xdir);
/* begin and end can be outside the array index, if the window is partially
* off the screen
*/
last_edge = edges->len - 1;
begin = CLAMP (begin, 0, last_edge);
end = CLAMP (end, 0, last_edge);
/* Loop over all these edges we're moving past/to. */
i = begin;
while ((increasing && i <= end) ||
(!increasing && i >= end))
{
gboolean edges_align;
MetaEdge *edge = g_array_index (edges, MetaEdge*, i);
int compare = xdir ? edge->rect.x : edge->rect.y;
/* Find out if this edge is relevant */
edges_align = meta_rectangle_edge_aligns (new_rect, edge) ||
meta_rectangle_edge_aligns (old_rect, edge);
/* Nothing to do unless the edges align */
if (!edges_align)
{
/* Go to the next edge in the range */
i += increment;
continue;
}
/* Rest is easier to read if we split on keyboard vs. mouse op */
if (keyboard_op)
{
if ((old_pos < compare && compare < new_pos) ||
(old_pos > compare && compare > new_pos))
return compare;
}
else /* mouse op */
{
int threshold;
/* TIMEOUT RESISTANCE: If the edge is relevant and we're moving
* towards it, then we may want to have some kind of time delay
* before the user can move past this edge.
*/
if (movement_towards_edge (edge->side_type, increment))
{
/* First, determine the length of time for the resistance */
int timeout_length_ms = 0;
switch (edge->edge_type)
{
case META_EDGE_WINDOW:
timeout_length_ms = TIMEOUT_RESISTANCE_LENGTH_MS_WINDOW;
break;
case META_EDGE_MONITOR:
timeout_length_ms = TIMEOUT_RESISTANCE_LENGTH_MS_MONITOR;
break;
case META_EDGE_SCREEN:
timeout_length_ms = TIMEOUT_RESISTANCE_LENGTH_MS_SCREEN;
break;
}
if (!resistance_data->timeout_setup &&
timeout_length_ms != 0)
{
resistance_data->timeout_id =
g_timeout_add (timeout_length_ms,
edge_resistance_timeout,
resistance_data);
g_source_set_name_by_id (resistance_data->timeout_id,
"[mutter] edge_resistance_timeout");
resistance_data->timeout_setup = TRUE;
resistance_data->timeout_edge_pos = compare;
resistance_data->timeout_over = FALSE;
resistance_data->timeout_func = timeout_func;
resistance_data->window = window;
}
if (!resistance_data->timeout_over &&
timeout_length_ms != 0)
return compare;
}
/* PIXEL DISTANCE MOUSE RESISTANCE: If the edge matters and the
* user hasn't moved at least threshold pixels past this edge,
* stop movement at this edge. (Note that this is different from
* keyboard resistance precisely because keyboard move ops are
* relative to previous positions, whereas mouse move ops are
* relative to differences in mouse position and mouse position
* is an absolute quantity rather than a relative quantity)
*/
/* First, determine the threshold */
threshold = 0;
switch (edge->edge_type)
{
case META_EDGE_WINDOW:
if (movement_towards_edge (edge->side_type, increment))
threshold = PIXEL_DISTANCE_THRESHOLD_TOWARDS_WINDOW;
else
threshold = PIXEL_DISTANCE_THRESHOLD_AWAYFROM_WINDOW;
break;
case META_EDGE_MONITOR:
if (movement_towards_edge (edge->side_type, increment))
threshold = PIXEL_DISTANCE_THRESHOLD_TOWARDS_MONITOR;
else
threshold = PIXEL_DISTANCE_THRESHOLD_AWAYFROM_MONITOR;
break;
case META_EDGE_SCREEN:
if (movement_towards_edge (edge->side_type, increment))
threshold = PIXEL_DISTANCE_THRESHOLD_TOWARDS_SCREEN;
else
threshold = PIXEL_DISTANCE_THRESHOLD_AWAYFROM_SCREEN;
break;
}
if (ABS (compare - new_pos) < threshold)
return compare;
}
/* Go to the next edge in the range */
i += increment;
}
return new_pos;
}
static int
apply_edge_snapping (int old_pos,
int new_pos,
const MetaRectangle *new_rect,
GArray *edges,
gboolean xdir,
gboolean keyboard_op)
{
int snap_to;
if (old_pos == new_pos)
return new_pos;
snap_to = find_nearest_position (edges,
new_pos,
old_pos,
new_rect,
xdir,
keyboard_op);
/* If mouse snap-moving, the user could easily accidentally move just a
* couple pixels in a direction they didn't mean to move; so ignore snap
* movement in those cases unless it's only a small number of pixels
* anyway.
*/
if (!keyboard_op &&
ABS (snap_to - old_pos) >= 8 &&
ABS (new_pos - old_pos) < 8)
return old_pos;
else
/* Otherwise, return the snapping position found */
return snap_to;
}
/* This function takes the position (including any frame) of the window and
* a proposed new position (ignoring edge resistance/snapping), and then
* applies edge resistance to EACH edge (separately) updating new_outer.
* It returns true if new_outer is modified, false otherwise.
*
* display->grab_edge_resistance_data MUST already be setup or calling this
* function will cause a crash.
*/
static gboolean
apply_edge_resistance_to_each_side (MetaDisplay *display,
MetaWindow *window,
const MetaRectangle *old_outer,
MetaRectangle *new_outer,
GSourceFunc timeout_func,
gboolean auto_snap,
gboolean keyboard_op,
gboolean is_resize)
{
MetaEdgeResistanceData *edge_data;
MetaRectangle modified_rect;
gboolean modified;
int new_left, new_right, new_top, new_bottom;
if (display->grab_edge_resistance_data == NULL)
compute_resistance_and_snapping_edges (display);
edge_data = display->grab_edge_resistance_data;
if (auto_snap)
{
/* Do the auto snapping instead of normal edge resistance; in all
* cases, we allow snapping to opposite kinds of edges (e.g. left
* sides of windows to both left and right edges.
*/
new_left = apply_edge_snapping (BOX_LEFT (*old_outer),
BOX_LEFT (*new_outer),
new_outer,
edge_data->left_edges,
TRUE,
keyboard_op);
new_right = apply_edge_snapping (BOX_RIGHT (*old_outer),
BOX_RIGHT (*new_outer),
new_outer,
edge_data->right_edges,
TRUE,
keyboard_op);
new_top = apply_edge_snapping (BOX_TOP (*old_outer),
BOX_TOP (*new_outer),
new_outer,
edge_data->top_edges,
FALSE,
keyboard_op);
new_bottom = apply_edge_snapping (BOX_BOTTOM (*old_outer),
BOX_BOTTOM (*new_outer),
new_outer,
edge_data->bottom_edges,
FALSE,
keyboard_op);
}
else
{
/* Disable edge resistance for resizes when windows have size
* increment hints; see #346782. For all other cases, apply
* them.
*/
if (!is_resize || window->size_hints.width_inc == 1)
{
/* Now, apply the normal horizontal edge resistance */
new_left = apply_edge_resistance (window,
BOX_LEFT (*old_outer),
BOX_LEFT (*new_outer),
old_outer,
new_outer,
edge_data->left_edges,
&edge_data->left_data,
timeout_func,
TRUE,
keyboard_op);
new_right = apply_edge_resistance (window,
BOX_RIGHT (*old_outer),
BOX_RIGHT (*new_outer),
old_outer,
new_outer,
edge_data->right_edges,
&edge_data->right_data,
timeout_func,
TRUE,
keyboard_op);
}
else
{
new_left = new_outer->x;
new_right = new_outer->x + new_outer->width;
}
/* Same for vertical resizes... */
if (!is_resize || window->size_hints.height_inc == 1)
{
new_top = apply_edge_resistance (window,
BOX_TOP (*old_outer),
BOX_TOP (*new_outer),
old_outer,
new_outer,
edge_data->top_edges,
&edge_data->top_data,
timeout_func,
FALSE,
keyboard_op);
new_bottom = apply_edge_resistance (window,
BOX_BOTTOM (*old_outer),
BOX_BOTTOM (*new_outer),
old_outer,
new_outer,
edge_data->bottom_edges,
&edge_data->bottom_data,
timeout_func,
FALSE,
keyboard_op);
}
else
{
new_top = new_outer->y;
new_bottom = new_outer->y + new_outer->height;
}
}
/* Determine whether anything changed, and save the changes */
modified_rect = meta_rect (new_left,
new_top,
new_right - new_left,
new_bottom - new_top);
modified = !meta_rectangle_equal (new_outer, &modified_rect);
*new_outer = modified_rect;
return modified;
}
void
meta_display_cleanup_edges (MetaDisplay *display)
{
guint i,j;
MetaEdgeResistanceData *edge_data = display->grab_edge_resistance_data;
GHashTable *edges_to_be_freed;
if (edge_data == NULL) /* Not currently cached */
return;
/* We first need to clean out any window edges */
edges_to_be_freed = g_hash_table_new_full (g_direct_hash, g_direct_equal,
g_free, NULL);
for (i = 0; i < 4; i++)
{
GArray *tmp = NULL;
MetaSide side;
switch (i)
{
case 0:
tmp = edge_data->left_edges;
side = META_SIDE_LEFT;
break;
case 1:
tmp = edge_data->right_edges;
side = META_SIDE_RIGHT;
break;
case 2:
tmp = edge_data->top_edges;
side = META_SIDE_TOP;
break;
case 3:
tmp = edge_data->bottom_edges;
side = META_SIDE_BOTTOM;
break;
default:
g_assert_not_reached ();
}
for (j = 0; j < tmp->len; j++)
{
MetaEdge *edge = g_array_index (tmp, MetaEdge*, j);
if (edge->edge_type == META_EDGE_WINDOW &&
edge->side_type == side)
{
/* The same edge will appear in two arrays, and we can't free
* it yet we still need to compare edge->side_type for the other
* array that it is in. So store it in a hash table for later
* freeing. Could also do this in a simple linked list.
*/
g_hash_table_insert (edges_to_be_freed, edge, edge);
}
}
}
/* Now free all the window edges (the key destroy function is g_free) */
g_hash_table_destroy (edges_to_be_freed);
/* Now free the arrays and data */
g_array_free (edge_data->left_edges, TRUE);
g_array_free (edge_data->right_edges, TRUE);
g_array_free (edge_data->top_edges, TRUE);
g_array_free (edge_data->bottom_edges, TRUE);
edge_data->left_edges = NULL;
edge_data->right_edges = NULL;
edge_data->top_edges = NULL;
edge_data->bottom_edges = NULL;
/* Cleanup the timeouts */
if (edge_data->left_data.timeout_setup &&
edge_data->left_data.timeout_id != 0)
g_source_remove (edge_data->left_data.timeout_id);
if (edge_data->right_data.timeout_setup &&
edge_data->right_data.timeout_id != 0)
g_source_remove (edge_data->right_data.timeout_id);
if (edge_data->top_data.timeout_setup &&
edge_data->top_data.timeout_id != 0)
g_source_remove (edge_data->top_data.timeout_id);
if (edge_data->bottom_data.timeout_setup &&
edge_data->bottom_data.timeout_id != 0)
g_source_remove (edge_data->bottom_data.timeout_id);
g_free (display->grab_edge_resistance_data);
display->grab_edge_resistance_data = NULL;
}
static int
stupid_sort_requiring_extra_pointer_dereference (gconstpointer a,
gconstpointer b)
{
const MetaEdge * const *a_edge = a;
const MetaEdge * const *b_edge = b;
return meta_rectangle_edge_cmp_ignore_type (*a_edge, *b_edge);
}
static void
cache_edges (MetaDisplay *display,
GList *window_edges,
GList *monitor_edges,
GList *screen_edges)
{
MetaEdgeResistanceData *edge_data;
GList *tmp;
int num_left, num_right, num_top, num_bottom;
int i;
/*
* 0th: Print debugging information to the log about the edges
*/
#ifdef WITH_VERBOSE_MODE
if (meta_is_verbose())
{
int max_edges = MAX (MAX( g_list_length (window_edges),
g_list_length (monitor_edges)),
g_list_length (screen_edges));
char big_buffer[(EDGE_LENGTH+2)*max_edges];
meta_rectangle_edge_list_to_string (window_edges, ", ", big_buffer);
meta_topic (META_DEBUG_EDGE_RESISTANCE,
"Window edges for resistance : %s\n", big_buffer);
meta_rectangle_edge_list_to_string (monitor_edges, ", ", big_buffer);
meta_topic (META_DEBUG_EDGE_RESISTANCE,
"Monitor edges for resistance: %s\n", big_buffer);
meta_rectangle_edge_list_to_string (screen_edges, ", ", big_buffer);
meta_topic (META_DEBUG_EDGE_RESISTANCE,
"Screen edges for resistance : %s\n", big_buffer);
}
#endif
/*
* 1st: Get the total number of each kind of edge
*/
num_left = num_right = num_top = num_bottom = 0;
for (i = 0; i < 3; i++)
{
tmp = NULL;
switch (i)
{
case 0:
tmp = window_edges;
break;
case 1:
tmp = monitor_edges;
break;
case 2:
tmp = screen_edges;
break;
default:
g_assert_not_reached ();
}
while (tmp)
{
MetaEdge *edge = tmp->data;
switch (edge->side_type)
{
case META_SIDE_LEFT:
num_left++;
break;
case META_SIDE_RIGHT:
num_right++;
break;
case META_SIDE_TOP:
num_top++;
break;
case META_SIDE_BOTTOM:
num_bottom++;
break;
default:
g_assert_not_reached ();
}
tmp = tmp->next;
}
}
/*
* 2nd: Allocate the edges
*/
g_assert (display->grab_edge_resistance_data == NULL);
display->grab_edge_resistance_data = g_new0 (MetaEdgeResistanceData, 1);
edge_data = display->grab_edge_resistance_data;
edge_data->left_edges = g_array_sized_new (FALSE,
FALSE,
sizeof(MetaEdge*),
num_left + num_right);
edge_data->right_edges = g_array_sized_new (FALSE,
FALSE,
sizeof(MetaEdge*),
num_left + num_right);
edge_data->top_edges = g_array_sized_new (FALSE,
FALSE,
sizeof(MetaEdge*),
num_top + num_bottom);
edge_data->bottom_edges = g_array_sized_new (FALSE,
FALSE,
sizeof(MetaEdge*),
num_top + num_bottom);
/*
* 3rd: Add the edges to the arrays
*/
for (i = 0; i < 3; i++)
{
tmp = NULL;
switch (i)
{
case 0:
tmp = window_edges;
break;
case 1:
tmp = monitor_edges;
break;
case 2:
tmp = screen_edges;
break;
default:
g_assert_not_reached ();
}
while (tmp)
{
MetaEdge *edge = tmp->data;
switch (edge->side_type)
{
case META_SIDE_LEFT:
case META_SIDE_RIGHT:
g_array_append_val (edge_data->left_edges, edge);
g_array_append_val (edge_data->right_edges, edge);
break;
case META_SIDE_TOP:
case META_SIDE_BOTTOM:
g_array_append_val (edge_data->top_edges, edge);
g_array_append_val (edge_data->bottom_edges, edge);
break;
default:
g_assert_not_reached ();
}
tmp = tmp->next;
}
}
/*
* 4th: Sort the arrays (FIXME: This is kinda dumb since the arrays were
* individually sorted earlier and we could have done this faster and
* avoided this sort by sticking them into the array with some simple
* merging of the lists).
*/
g_array_sort (display->grab_edge_resistance_data->left_edges,
stupid_sort_requiring_extra_pointer_dereference);
g_array_sort (display->grab_edge_resistance_data->right_edges,
stupid_sort_requiring_extra_pointer_dereference);
g_array_sort (display->grab_edge_resistance_data->top_edges,
stupid_sort_requiring_extra_pointer_dereference);
g_array_sort (display->grab_edge_resistance_data->bottom_edges,
stupid_sort_requiring_extra_pointer_dereference);
}
static void
initialize_grab_edge_resistance_data (MetaDisplay *display)
{
MetaEdgeResistanceData *edge_data = display->grab_edge_resistance_data;
edge_data->left_data.timeout_setup = FALSE;
edge_data->right_data.timeout_setup = FALSE;
edge_data->top_data.timeout_setup = FALSE;
edge_data->bottom_data.timeout_setup = FALSE;
edge_data->left_data.keyboard_buildup = 0;
edge_data->right_data.keyboard_buildup = 0;
edge_data->top_data.keyboard_buildup = 0;
edge_data->bottom_data.keyboard_buildup = 0;
}
static void
compute_resistance_and_snapping_edges (MetaDisplay *display)
{
GList *stacked_windows;
GList *cur_window_iter;
GList *edges;
/* Lists of window positions (rects) and their relative stacking positions */
int stack_position;
GSList *obscuring_windows, *window_stacking;
/* The portions of the above lists that still remain at the stacking position
* in the layer that we are working on
*/
GSList *rem_windows, *rem_win_stacking;
g_assert (display->grab_window != NULL);
meta_topic (META_DEBUG_WINDOW_OPS,
"Computing edges to resist-movement or snap-to for %s.\n",
display->grab_window->desc);
/*
* 1st: Get the list of relevant windows, from bottom to top
*/
stacked_windows =
meta_stack_list_windows (display->screen->stack,
display->screen->active_workspace);
/*
* 2nd: we need to separate that stacked list into a list of windows that
* can obscure other edges. To make sure we only have windows obscuring
* those below it instead of going both ways, we also need to keep a
* counter list. Messy, I know.
*/
obscuring_windows = window_stacking = NULL;
cur_window_iter = stacked_windows;
stack_position = 0;
while (cur_window_iter != NULL)
{
MetaWindow *cur_window = cur_window_iter->data;
if (WINDOW_EDGES_RELEVANT (cur_window, display))
{
MetaRectangle *new_rect;
new_rect = g_new (MetaRectangle, 1);
meta_window_get_frame_rect (cur_window, new_rect);
obscuring_windows = g_slist_prepend (obscuring_windows, new_rect);
window_stacking =
g_slist_prepend (window_stacking, GINT_TO_POINTER (stack_position));
}
stack_position++;
cur_window_iter = cur_window_iter->next;
}
/* Put 'em in bottom to top order */
rem_windows = obscuring_windows = g_slist_reverse (obscuring_windows);
rem_win_stacking = window_stacking = g_slist_reverse (window_stacking);
/*
* 3rd: loop over the windows again, this time getting the edges from
* them and removing intersections with the relevant obscuring_windows &
* obscuring_docks.
*/
edges = NULL;
stack_position = 0;
cur_window_iter = stacked_windows;
while (cur_window_iter != NULL)
{
MetaRectangle cur_rect;
MetaWindow *cur_window = cur_window_iter->data;
meta_window_get_frame_rect (cur_window, &cur_rect);
/* Check if we want to use this window's edges for edge
* resistance (note that dock edges are considered screen edges
* which are handled separately
*/
if (WINDOW_EDGES_RELEVANT (cur_window, display) &&
cur_window->type != META_WINDOW_DOCK)
{
GList *new_edges;
MetaEdge *new_edge;
MetaRectangle reduced;
/* We don't care about snapping to any portion of the window that
* is offscreen (we also don't care about parts of edges covered
* by other windows or DOCKS, but that's handled below).
*/
meta_rectangle_intersect (&cur_rect,
&display->screen->rect,
&reduced);
new_edges = NULL;
/* Left side of this window is resistance for the right edge of
* the window being moved.
*/
new_edge = g_new (MetaEdge, 1);
new_edge->rect = reduced;
new_edge->rect.width = 0;
new_edge->side_type = META_SIDE_RIGHT;
new_edge->edge_type = META_EDGE_WINDOW;
new_edges = g_list_prepend (new_edges, new_edge);
/* Right side of this window is resistance for the left edge of
* the window being moved.
*/
new_edge = g_new (MetaEdge, 1);
new_edge->rect = reduced;
new_edge->rect.x += new_edge->rect.width;
new_edge->rect.width = 0;
new_edge->side_type = META_SIDE_LEFT;
new_edge->edge_type = META_EDGE_WINDOW;
new_edges = g_list_prepend (new_edges, new_edge);
/* Top side of this window is resistance for the bottom edge of
* the window being moved.
*/
new_edge = g_new (MetaEdge, 1);
new_edge->rect = reduced;
new_edge->rect.height = 0;
new_edge->side_type = META_SIDE_BOTTOM;
new_edge->edge_type = META_EDGE_WINDOW;
new_edges = g_list_prepend (new_edges, new_edge);
/* Top side of this window is resistance for the bottom edge of
* the window being moved.
*/
new_edge = g_new (MetaEdge, 1);
new_edge->rect = reduced;
new_edge->rect.y += new_edge->rect.height;
new_edge->rect.height = 0;
new_edge->side_type = META_SIDE_TOP;
new_edge->edge_type = META_EDGE_WINDOW;
new_edges = g_list_prepend (new_edges, new_edge);
/* Update the remaining windows to only those at a higher
* stacking position than this one.
*/
while (rem_win_stacking &&
stack_position >= GPOINTER_TO_INT (rem_win_stacking->data))
{
rem_windows = rem_windows->next;
rem_win_stacking = rem_win_stacking->next;
}
/* Remove edge portions overlapped by rem_windows and rem_docks */
new_edges =
meta_rectangle_remove_intersections_with_boxes_from_edges (
new_edges,
rem_windows);
/* Save the new edges */
edges = g_list_concat (new_edges, edges);
}
stack_position++;
cur_window_iter = cur_window_iter->next;
}
/*
* 4th: Free the extra memory not needed and sort the list
*/
g_list_free (stacked_windows);
/* Free the memory used by the obscuring windows/docks lists */
g_slist_free (window_stacking);
/* FIXME: Shouldn't there be a helper function to make this one line of code
* to free a list instead of four ugly ones?
*/
g_slist_foreach (obscuring_windows,
(void (*)(gpointer,gpointer))&g_free, /* ew, for ugly */
NULL);
g_slist_free (obscuring_windows);
/* Sort the list. FIXME: Should I bother with this sorting? I just
* sort again later in cache_edges() anyway...
*/
edges = g_list_sort (edges, meta_rectangle_edge_cmp);
/*
* 5th: Cache the combination of these edges with the onscreen and
* monitor edges in an array for quick access. Free the edges since
* they've been cached elsewhere.
*/
cache_edges (display,
edges,
display->screen->active_workspace->monitor_edges,
display->screen->active_workspace->screen_edges);
g_list_free (edges);
/*
* 6th: Initialize the resistance timeouts and buildups
*/
initialize_grab_edge_resistance_data (display);
}
/* Note that old_[xy] and new_[xy] are with respect to inner positions of
* the window.
*/
void
meta_window_edge_resistance_for_move (MetaWindow *window,
int old_x,
int old_y,
int *new_x,
int *new_y,
GSourceFunc timeout_func,
gboolean snap,
gboolean is_keyboard_op)
{
MetaRectangle old_outer, proposed_outer, new_outer;
gboolean is_resize;
meta_window_get_frame_rect (window, &old_outer);
proposed_outer = old_outer;
proposed_outer.x += (*new_x - old_x);
proposed_outer.y += (*new_y - old_y);
new_outer = proposed_outer;
window->display->grab_last_user_action_was_snap = snap;
is_resize = FALSE;
if (apply_edge_resistance_to_each_side (window->display,
window,
&old_outer,
&new_outer,
timeout_func,
snap,
is_keyboard_op,
is_resize))
{
/* apply_edge_resistance_to_each_side independently applies
* resistance to both the right and left edges of new_outer as both
* could meet areas of resistance. But we don't want a resize, so we
* just have both edges move according to the stricter of the
* resistances. Same thing goes for top & bottom edges.
*/
MetaRectangle *reference;
int left_change, right_change, smaller_x_change;
int top_change, bottom_change, smaller_y_change;
if (snap && !is_keyboard_op)
reference = &proposed_outer;
else
reference = &old_outer;
left_change = BOX_LEFT (new_outer) - BOX_LEFT (*reference);
right_change = BOX_RIGHT (new_outer) - BOX_RIGHT (*reference);
if ( snap && is_keyboard_op && left_change == 0)
smaller_x_change = right_change;
else if (snap && is_keyboard_op && right_change == 0)
smaller_x_change = left_change;
else if (ABS (left_change) < ABS (right_change))
smaller_x_change = left_change;
else
smaller_x_change = right_change;
top_change = BOX_TOP (new_outer) - BOX_TOP (*reference);
bottom_change = BOX_BOTTOM (new_outer) - BOX_BOTTOM (*reference);
if ( snap && is_keyboard_op && top_change == 0)
smaller_y_change = bottom_change;
else if (snap && is_keyboard_op && bottom_change == 0)
smaller_y_change = top_change;
else if (ABS (top_change) < ABS (bottom_change))
smaller_y_change = top_change;
else
smaller_y_change = bottom_change;
*new_x = old_x + smaller_x_change +
(BOX_LEFT (*reference) - BOX_LEFT (old_outer));
*new_y = old_y + smaller_y_change +
(BOX_TOP (*reference) - BOX_TOP (old_outer));
meta_topic (META_DEBUG_EDGE_RESISTANCE,
"outer x & y move-to coordinate changed from %d,%d to %d,%d\n",
proposed_outer.x, proposed_outer.y,
old_outer.x + (*new_x - old_x),
old_outer.y + (*new_y - old_y));
}
}
/* Note that old_(width|height) and new_(width|height) are with respect to
* sizes of the inner window.
*/
void
meta_window_edge_resistance_for_resize (MetaWindow *window,
int old_width,
int old_height,
int *new_width,
int *new_height,
int gravity,
GSourceFunc timeout_func,
gboolean snap,
gboolean is_keyboard_op)
{
MetaRectangle old_outer, new_outer;
int proposed_outer_width, proposed_outer_height;
gboolean is_resize;
meta_window_get_frame_rect (window, &old_outer);
proposed_outer_width = old_outer.width + (*new_width - old_width);
proposed_outer_height = old_outer.height + (*new_height - old_height);
meta_rectangle_resize_with_gravity (&old_outer,
&new_outer,
gravity,
proposed_outer_width,
proposed_outer_height);
window->display->grab_last_user_action_was_snap = snap;
is_resize = TRUE;
if (apply_edge_resistance_to_each_side (window->display,
window,
&old_outer,
&new_outer,
timeout_func,
snap,
is_keyboard_op,
is_resize))
{
*new_width = old_width + (new_outer.width - old_outer.width);
*new_height = old_height + (new_outer.height - old_outer.height);
meta_topic (META_DEBUG_EDGE_RESISTANCE,
"outer width & height got changed from %d,%d to %d,%d\n",
proposed_outer_width, proposed_outer_height,
new_outer.width, new_outer.height);
}
}