2 * Copyright (C) 2007-2010 Openismus GmbH
5 * Mathias Hasselmann <mathias@openismus.com>
6 * Tristan Van Berkom <tristan.van.berkom@gmail.com>
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library. If not, see <http://www.gnu.org/licenses/>.
24 #include "gtksizerequest.h"
28 #include "gtkprivate.h"
29 #include "gtksizegroup-private.h"
30 #include "gtkwidgetprivate.h"
31 #include "deprecated/gtkstyle.h"
34 #ifndef G_DISABLE_CHECKS
35 static GQuark recursion_check_quark = 0;
36 #endif /* G_DISABLE_CHECKS */
39 push_recursion_check (GtkWidget *widget,
40 GtkSizeGroupMode orientation,
43 #ifndef G_DISABLE_CHECKS
44 const char *previous_method;
47 if (recursion_check_quark == 0)
48 recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
50 previous_method = g_object_get_qdata (G_OBJECT (widget), recursion_check_quark);
52 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
54 method = for_size < 0 ? "get_width" : "get_width_for_height";
58 method = for_size < 0 ? "get_height" : "get_height_for_width";
61 if (previous_method != NULL)
63 g_warning ("%s %p: widget tried to gtk_widget_%s inside "
64 " GtkWidget ::%s implementation. "
65 "Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
66 "directly rather than using gtk_widget_%s",
67 G_OBJECT_TYPE_NAME (widget), widget,
68 method, previous_method,
72 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, (char*) method);
73 #endif /* G_DISABLE_CHECKS */
77 pop_recursion_check (GtkWidget *widget,
78 GtkSizeGroupMode orientation)
80 #ifndef G_DISABLE_CHECKS
81 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
87 clear_cache (SizeRequestCache *cache,
88 GtkSizeGroupMode orientation)
93 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
95 sizes = cache->widths;
98 cache->cached_widths = 0;
99 cache->last_cached_width = 0;
100 cache->cached_base_width = FALSE;
104 sizes = cache->heights;
106 cache->heights = NULL;
107 cache->cached_heights = 0;
108 cache->last_cached_height = 0;
109 cache->cached_base_height = FALSE;
114 for (i = 0; i < GTK_SIZE_REQUEST_CACHED_SIZES && sizes[i] != NULL; i++)
115 g_slice_free (SizeRequest, sizes[i]);
117 g_slice_free1 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES, sizes);
122 _gtk_widget_free_cached_sizes (GtkWidget *widget)
124 SizeRequestCache *cache;
126 cache = _gtk_widget_peek_request_cache (widget);
128 clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
129 clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
132 /* This function checks if 'request_needed' flag is present
133 * and resets the cache state if a request is needed for
134 * a given orientation.
136 static SizeRequestCache *
137 init_cache (GtkWidget *widget)
139 SizeRequestCache *cache;
141 cache = _gtk_widget_peek_request_cache (widget);
143 if (_gtk_widget_get_width_request_needed (widget))
144 clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
146 if (_gtk_widget_get_height_request_needed (widget))
147 clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
152 /* looks for a cached size request for this for_size. If not
153 * found, returns the oldest entry so it can be overwritten
155 * Note that this caching code was originally derived from
156 * the Clutter toolkit but has evolved for other GTK+ requirements.
159 get_cached_size (GtkWidget *widget,
160 GtkSizeGroupMode orientation,
164 SizeRequestCache *cache;
165 SizeRequest **cached_sizes;
168 cache = init_cache (widget);
172 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
174 *result = &cache->cached_width;
175 return cache->cached_base_width;
179 *result = &cache->cached_height;
180 return cache->cached_base_height;
184 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
186 cached_sizes = cache->widths;
187 n_sizes = cache->cached_widths;
191 cached_sizes = cache->heights;
192 n_sizes = cache->cached_heights;
195 /* Search for an already cached size */
196 for (i = 0; i < n_sizes; i++)
198 if (cached_sizes[i]->lower_for_size <= for_size &&
199 cached_sizes[i]->upper_for_size >= for_size)
201 *result = &cached_sizes[i]->cached_size;
210 commit_cached_size (GtkWidget *widget,
211 GtkSizeGroupMode orientation,
216 SizeRequestCache *cache;
217 SizeRequest **cached_sizes;
220 cache = _gtk_widget_peek_request_cache (widget);
222 /* First handle caching of the base requests */
225 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
227 cache->cached_width.minimum_size = minimum_size;
228 cache->cached_width.natural_size = natural_size;
229 cache->cached_base_width = TRUE;
233 cache->cached_height.minimum_size = minimum_size;
234 cache->cached_height.natural_size = natural_size;
235 cache->cached_base_height = TRUE;
240 /* Check if the minimum_size and natural_size is already
241 * in the cache and if this result can be used to extend
244 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
246 cached_sizes = cache->widths;
247 n_sizes = cache->cached_widths;
251 cached_sizes = cache->heights;
252 n_sizes = cache->cached_heights;
255 for (i = 0; i < n_sizes; i++)
257 if (cached_sizes[i]->cached_size.minimum_size == minimum_size &&
258 cached_sizes[i]->cached_size.natural_size == natural_size)
260 cached_sizes[i]->lower_for_size = MIN (cached_sizes[i]->lower_for_size, for_size);
261 cached_sizes[i]->upper_for_size = MAX (cached_sizes[i]->upper_for_size, for_size);
266 /* If not found, pull a new size from the cache, the returned size cache
267 * will immediately be used to cache the new computed size so we go ahead
268 * and increment the last_cached_width/height right away */
269 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
271 if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
273 cache->cached_widths++;
274 cache->last_cached_width = cache->cached_widths - 1;
278 if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
279 cache->last_cached_width = 0;
283 cache->widths = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
285 if (!cache->widths[cache->last_cached_width])
286 cache->widths[cache->last_cached_width] = g_slice_new (SizeRequest);
288 cache->widths[cache->last_cached_width]->lower_for_size = for_size;
289 cache->widths[cache->last_cached_width]->upper_for_size = for_size;
290 cache->widths[cache->last_cached_width]->cached_size.minimum_size = minimum_size;
291 cache->widths[cache->last_cached_width]->cached_size.natural_size = natural_size;
293 else /* GTK_SIZE_GROUP_VERTICAL */
295 if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
297 cache->cached_heights++;
298 cache->last_cached_height = cache->cached_heights - 1;
302 if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
303 cache->last_cached_height = 0;
307 cache->heights = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
309 if (!cache->heights[cache->last_cached_height])
310 cache->heights[cache->last_cached_height] = g_slice_new (SizeRequest);
312 cache->heights[cache->last_cached_height]->lower_for_size = for_size;
313 cache->heights[cache->last_cached_height]->upper_for_size = for_size;
314 cache->heights[cache->last_cached_height]->cached_size.minimum_size = minimum_size;
315 cache->heights[cache->last_cached_height]->cached_size.natural_size = natural_size;
320 get_vfunc_name (GtkSizeGroupMode orientation,
323 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
324 return for_size < 0 ? "get_preferred_width" : "get_preferred_width_for_height";
326 return for_size < 0 ? "get_preferred_height" : "get_preferred_height_for_width";
330 gtk_widget_query_size_for_orientation (GtkWidget *widget,
331 GtkSizeGroupMode orientation,
336 CachedSize *cached_size;
337 gboolean found_in_cache = FALSE;
341 found_in_cache = get_cached_size (widget, orientation, for_size, &cached_size);
345 gint adjusted_min, adjusted_natural, adjusted_for_size = for_size;
347 gtk_widget_ensure_style (widget);
349 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
351 if (for_size < 0 || gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
353 push_recursion_check (widget, orientation, for_size);
354 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
355 pop_recursion_check (widget, orientation);
359 gint ignored_position = 0;
363 /* Pull the base natural height from the cache as it's needed to adjust
364 * the proposed 'for_size' */
365 gtk_widget_get_preferred_height (widget, &minimum_height, &natural_height);
367 /* convert for_size to unadjusted height (for_size is a proposed allocation) */
368 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
369 GTK_ORIENTATION_VERTICAL,
375 push_recursion_check (widget, orientation, for_size);
376 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget,
377 MAX (adjusted_for_size, minimum_height),
378 &min_size, &nat_size);
379 pop_recursion_check (widget, orientation);
384 if (for_size < 0 || gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
386 push_recursion_check (widget, orientation, for_size);
387 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
388 pop_recursion_check (widget, orientation);
392 gint ignored_position = 0;
396 /* Pull the base natural width from the cache as it's needed to adjust
397 * the proposed 'for_size' */
398 gtk_widget_get_preferred_width (widget, &minimum_width, &natural_width);
400 /* convert for_size to unadjusted width (for_size is a proposed allocation) */
401 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
402 GTK_ORIENTATION_HORIZONTAL,
408 push_recursion_check (widget, orientation, for_size);
409 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget,
410 MAX (adjusted_for_size, minimum_width),
411 &min_size, &nat_size);
412 pop_recursion_check (widget, orientation);
416 if (min_size > nat_size)
418 g_warning ("%s %p reported min size %d and natural size %d in %s(); natural size must be >= min size",
419 G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size, get_vfunc_name (orientation, for_size));
422 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
423 _gtk_widget_set_width_request_needed (widget, FALSE);
425 _gtk_widget_set_height_request_needed (widget, FALSE);
427 adjusted_min = min_size;
428 adjusted_natural = nat_size;
429 GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
430 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
431 GTK_ORIENTATION_HORIZONTAL :
432 GTK_ORIENTATION_VERTICAL,
436 if (adjusted_min < min_size ||
437 adjusted_natural < nat_size)
439 g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
440 G_OBJECT_TYPE_NAME (widget), widget,
441 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
442 adjusted_min, adjusted_natural,
444 /* don't use the adjustment */
446 else if (adjusted_min > adjusted_natural)
448 g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
449 G_OBJECT_TYPE_NAME (widget), widget,
450 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
451 adjusted_min, adjusted_natural,
453 /* don't use the adjustment */
457 /* adjustment looks good */
458 min_size = adjusted_min;
459 nat_size = adjusted_natural;
462 commit_cached_size (widget, orientation, for_size, min_size, nat_size);
466 min_size = cached_size->minimum_size;
467 nat_size = cached_size->natural_size;
471 *minimum_size = min_size;
474 *natural_size = nat_size;
476 g_assert (min_size <= nat_size);
478 GTK_NOTE (SIZE_REQUEST,
479 g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
480 widget, G_OBJECT_TYPE_NAME (widget),
481 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
482 "width for height" : "height for width" ,
483 for_size, min_size, nat_size,
484 found_in_cache ? "yes" : "no"));
488 /* This is the main function that checks for a cached size and
489 * possibly queries the widget class to compute the size if it's
490 * not cached. If the for_size here is -1, then get_preferred_width()
491 * or get_preferred_height() will be used.
494 _gtk_widget_compute_size_for_orientation (GtkWidget *widget,
495 GtkSizeGroupMode mode,
503 gint min_result = 0, nat_result = 0;
505 if (G_LIKELY (!_gtk_widget_get_sizegroups (widget)))
507 gtk_widget_query_size_for_orientation (widget, mode, for_size, minimum, natural);
511 widgets = _gtk_size_group_get_widget_peers (widget, mode);
513 g_hash_table_foreach (widgets, (GHFunc) g_object_ref, NULL);
515 g_hash_table_iter_init (&iter, widgets);
516 while (g_hash_table_iter_next (&iter, &key, NULL))
518 GtkWidget *tmp_widget = key;
519 gint min_dimension, nat_dimension;
521 gtk_widget_query_size_for_orientation (tmp_widget, mode, for_size, &min_dimension, &nat_dimension);
523 min_result = MAX (min_result, min_dimension);
524 nat_result = MAX (nat_result, nat_dimension);
527 g_hash_table_foreach (widgets, (GHFunc) g_object_unref, NULL);
529 g_hash_table_destroy (widgets);
532 *minimum = min_result;
535 *natural = nat_result;
539 * gtk_widget_get_request_mode:
540 * @widget: a #GtkWidget instance
542 * Gets whether the widget prefers a height-for-width layout
543 * or a width-for-height layout.
545 * <note><para>#GtkBin widgets generally propagate the preference of
546 * their child, container widgets need to request something either in
547 * context of their children or in context of their allocation
548 * capabilities.</para></note>
550 * Returns: The #GtkSizeRequestMode preferred by @widget.
555 gtk_widget_get_request_mode (GtkWidget *widget)
557 g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_CONSTANT_SIZE);
559 return GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget);
563 * gtk_widget_get_preferred_width:
564 * @widget: a #GtkWidget instance
565 * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
566 * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
568 * Retrieves a widget's initial minimum and natural width.
570 * <note><para>This call is specific to height-for-width
571 * requests.</para></note>
573 * The returned request will be modified by the
574 * GtkWidgetClass::adjust_size_request virtual method and by any
575 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
576 * is the one that should be used for layout, not necessarily the one
577 * returned by the widget itself.
582 gtk_widget_get_preferred_width (GtkWidget *widget,
586 g_return_if_fail (GTK_IS_WIDGET (widget));
587 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
589 _gtk_widget_compute_size_for_orientation (widget,
590 GTK_SIZE_GROUP_HORIZONTAL,
598 * gtk_widget_get_preferred_height:
599 * @widget: a #GtkWidget instance
600 * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
601 * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
603 * Retrieves a widget's initial minimum and natural height.
605 * <note><para>This call is specific to width-for-height requests.</para></note>
607 * The returned request will be modified by the
608 * GtkWidgetClass::adjust_size_request virtual method and by any
609 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
610 * is the one that should be used for layout, not necessarily the one
611 * returned by the widget itself.
616 gtk_widget_get_preferred_height (GtkWidget *widget,
617 gint *minimum_height,
618 gint *natural_height)
620 g_return_if_fail (GTK_IS_WIDGET (widget));
621 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
623 _gtk_widget_compute_size_for_orientation (widget,
624 GTK_SIZE_GROUP_VERTICAL,
633 * gtk_widget_get_preferred_width_for_height:
634 * @widget: a #GtkWidget instance
635 * @height: the height which is available for allocation
636 * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
637 * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
639 * Retrieves a widget's minimum and natural width if it would be given
640 * the specified @height.
642 * The returned request will be modified by the
643 * GtkWidgetClass::adjust_size_request virtual method and by any
644 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
645 * is the one that should be used for layout, not necessarily the one
646 * returned by the widget itself.
651 gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
656 g_return_if_fail (GTK_IS_WIDGET (widget));
657 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
658 g_return_if_fail (height >= 0);
660 _gtk_widget_compute_size_for_orientation (widget,
661 GTK_SIZE_GROUP_HORIZONTAL,
668 * gtk_widget_get_preferred_height_for_width:
669 * @widget: a #GtkWidget instance
670 * @width: the width which is available for allocation
671 * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
672 * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
674 * Retrieves a widget's minimum and natural height if it would be given
675 * the specified @width.
677 * The returned request will be modified by the
678 * GtkWidgetClass::adjust_size_request virtual method and by any
679 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
680 * is the one that should be used for layout, not necessarily the one
681 * returned by the widget itself.
686 gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
688 gint *minimum_height,
689 gint *natural_height)
691 g_return_if_fail (GTK_IS_WIDGET (widget));
692 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
693 g_return_if_fail (width >= 0);
695 _gtk_widget_compute_size_for_orientation (widget,
696 GTK_SIZE_GROUP_VERTICAL,
703 * gtk_widget_get_preferred_size:
704 * @widget: a #GtkWidget instance
705 * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
706 * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
708 * Retrieves the minimum and natural size of a widget, taking
709 * into account the widget's preference for height-for-width management.
711 * This is used to retrieve a suitable size by container widgets which do
712 * not impose any restrictions on the child placement. It can be used
713 * to deduce toplevel window and menu sizes as well as child widgets in
714 * free-form containers such as GtkLayout.
716 * <note><para>Handle with care. Note that the natural height of a height-for-width
717 * widget will generally be a smaller size than the minimum height, since the required
718 * height for the natural width is generally smaller than the required height for
719 * the minimum width.</para></note>
724 gtk_widget_get_preferred_size (GtkWidget *widget,
725 GtkRequisition *minimum_size,
726 GtkRequisition *natural_size)
728 gint min_width, nat_width;
729 gint min_height, nat_height;
731 g_return_if_fail (GTK_IS_WIDGET (widget));
733 if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
735 gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
739 minimum_size->width = min_width;
740 gtk_widget_get_preferred_height_for_width (widget, min_width,
741 &minimum_size->height, NULL);
746 natural_size->width = nat_width;
747 gtk_widget_get_preferred_height_for_width (widget, nat_width,
748 NULL, &natural_size->height);
751 else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT or CONSTANT_SIZE */
753 gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
757 minimum_size->height = min_height;
758 gtk_widget_get_preferred_width_for_height (widget, min_height,
759 &minimum_size->width, NULL);
764 natural_size->height = nat_height;
765 gtk_widget_get_preferred_width_for_height (widget, nat_height,
766 NULL, &natural_size->width);
773 compare_gap (gconstpointer p1,
777 GtkRequestedSize *sizes = data;
778 const guint *c1 = p1;
779 const guint *c2 = p2;
781 const gint d1 = MAX (sizes[*c1].natural_size -
782 sizes[*c1].minimum_size,
784 const gint d2 = MAX (sizes[*c2].natural_size -
785 sizes[*c2].minimum_size,
788 gint delta = (d2 - d1);
797 * gtk_distribute_natural_allocation:
798 * @extra_space: Extra space to redistribute among children after subtracting
799 * minimum sizes and any child padding from the overall allocation
800 * @n_requested_sizes: Number of requests to fit into the allocation
801 * @sizes: An array of structs with a client pointer and a minimum/natural size
802 * in the orientation of the allocation.
804 * Distributes @extra_space to child @sizes by bringing smaller
805 * children up to natural size first.
807 * The remaining space will be added to the @minimum_size member of the
808 * GtkRequestedSize struct. If all sizes reach their natural size then
809 * the remaining space is returned.
811 * Returns: The remainder of @extra_space after redistributing space
815 gtk_distribute_natural_allocation (gint extra_space,
816 guint n_requested_sizes,
817 GtkRequestedSize *sizes)
822 g_return_val_if_fail (extra_space >= 0, 0);
824 spreading = g_newa (guint, n_requested_sizes);
826 for (i = 0; i < n_requested_sizes; i++)
829 /* Distribute the container's extra space c_gap. We want to assign
830 * this space such that the sum of extra space assigned to children
831 * (c^i_gap) is equal to c_cap. The case that there's not enough
832 * space for all children to take their natural size needs some
833 * attention. The goals we want to achieve are:
835 * a) Maximize number of children taking their natural size.
836 * b) The allocated size of children should be a continuous
837 * function of c_gap. That is, increasing the container size by
838 * one pixel should never make drastic changes in the distribution.
839 * c) If child i takes its natural size and child j doesn't,
840 * child j should have received at least as much gap as child i.
842 * The following code distributes the additional space by following
846 /* Sort descending by gap and position. */
847 g_qsort_with_data (spreading,
848 n_requested_sizes, sizeof (guint),
851 /* Distribute available space.
852 * This master piece of a loop was conceived by Behdad Esfahbod.
854 for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
856 /* Divide remaining space by number of remaining children.
857 * Sort order and reducing remaining space by assigned space
858 * ensures that space is distributed equally.
860 gint glue = (extra_space + i) / (i + 1);
861 gint gap = sizes[(spreading[i])].natural_size
862 - sizes[(spreading[i])].minimum_size;
864 gint extra = MIN (glue, gap);
866 sizes[spreading[i]].minimum_size += extra;
868 extra_space -= extra;