/* -*- 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, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301, USA. */ #include #include "edge-resistance.h" #include "boxes.h" #include "display-private.h" #include "workspace.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->screen == display->grab_screen && \ 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; } 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_XINERAMA = 32; const int PIXEL_DISTANCE_THRESHOLD_AWAYFROM_XINERAMA = 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_XINERAMA = 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_XINERAMA: timeout_length_ms = TIMEOUT_RESISTANCE_LENGTH_MS_XINERAMA; 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); 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 */ 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_XINERAMA: if (movement_towards_edge (edge->side_type, increment)) threshold = PIXEL_DISTANCE_THRESHOLD_TOWARDS_XINERAMA; else threshold = PIXEL_DISTANCE_THRESHOLD_AWAYFROM_XINERAMA; 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; default: threshold = 0; } 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 *xinerama_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 (xinerama_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 (xinerama_edges, ", ", big_buffer); meta_topic (META_DEBUG_EDGE_RESISTANCE, "Xinerama 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 = xinerama_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_new (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 = xinerama_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->grab_screen->stack, display->grab_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_outer_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_outer_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->grab_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); g_slist_free_full (obscuring_windows, g_free); /* 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 * xinerama edges in an array for quick access. Free the edges since * they've been cached elsewhere. */ cache_edges (display, edges, display->grab_screen->active_workspace->xinerama_edges, display->grab_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; if (window == window->display->grab_window && window->display->grab_wireframe_active) { meta_window_get_xor_rect (window, &window->display->grab_wireframe_rect, &old_outer); } else { meta_window_get_outer_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; if (window == window->display->grab_window && window->display->grab_wireframe_active) { meta_window_get_xor_rect (window, &window->display->grab_wireframe_rect, &old_outer); } else { meta_window_get_outer_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); } }