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gtk2/gtk/gtksizerequest.c
Matthias Clasen 2de4405c32 Move deprecated gtkwidget style api to gtkstyle
2011-11-02 08:10:42 -04:00

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/* gtksizerequest.c
* Copyright (C) 2007-2010 Openismus GmbH
*
* Authors:
* Mathias Hasselmann <mathias@openismus.com>
* Tristan Van Berkom <tristan.van.berkom@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <config.h>
#include "gtksizerequest.h"
#include "gtkdebug.h"
#include "gtkintl.h"
#include "gtkprivate.h"
#include "gtksizegroup-private.h"
#include "gtkwidgetprivate.h"
#include "deprecated/gtkstyle.h"
#ifndef G_DISABLE_CHECKS
static GQuark recursion_check_quark = 0;
#endif /* G_DISABLE_CHECKS */
static void
push_recursion_check (GtkWidget *widget,
GtkSizeGroupMode orientation,
gint for_size)
{
#ifndef G_DISABLE_CHECKS
const char *previous_method;
const char *method;
if (recursion_check_quark == 0)
recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
previous_method = g_object_get_qdata (G_OBJECT (widget), recursion_check_quark);
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
method = for_size < 0 ? "get_width" : "get_width_for_height";
}
else
{
method = for_size < 0 ? "get_height" : "get_height_for_width";
}
if (previous_method != NULL)
{
g_warning ("%s %p: widget tried to gtk_widget_%s inside "
" GtkWidget ::%s implementation. "
"Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
"directly rather than using gtk_widget_%s",
G_OBJECT_TYPE_NAME (widget), widget,
method, previous_method,
method, method);
}
g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, (char*) method);
#endif /* G_DISABLE_CHECKS */
}
static void
pop_recursion_check (GtkWidget *widget,
GtkSizeGroupMode orientation)
{
#ifndef G_DISABLE_CHECKS
g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
#endif
}
static void
clear_cache (SizeRequestCache *cache,
GtkSizeGroupMode orientation)
{
SizeRequest **sizes;
gint i;
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
sizes = cache->widths;
cache->widths = NULL;
cache->cached_widths = 0;
cache->last_cached_width = 0;
cache->cached_base_width = FALSE;
}
else
{
sizes = cache->heights;
cache->heights = NULL;
cache->cached_heights = 0;
cache->last_cached_height = 0;
cache->cached_base_height = FALSE;
}
if (sizes)
{
for (i = 0; i < GTK_SIZE_REQUEST_CACHED_SIZES && sizes[i] != NULL; i++)
g_slice_free (SizeRequest, sizes[i]);
g_slice_free1 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES, sizes);
}
}
void
_gtk_widget_free_cached_sizes (GtkWidget *widget)
{
SizeRequestCache *cache;
cache = _gtk_widget_peek_request_cache (widget);
clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
}
/* This function checks if 'request_needed' flag is present
* and resets the cache state if a request is needed for
* a given orientation.
*/
static SizeRequestCache *
init_cache (GtkWidget *widget)
{
SizeRequestCache *cache;
cache = _gtk_widget_peek_request_cache (widget);
if (_gtk_widget_get_width_request_needed (widget))
clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
if (_gtk_widget_get_height_request_needed (widget))
clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
return cache;
}
/* looks for a cached size request for this for_size. If not
* found, returns the oldest entry so it can be overwritten
*
* Note that this caching code was originally derived from
* the Clutter toolkit but has evolved for other GTK+ requirements.
*/
static gboolean
get_cached_size (GtkWidget *widget,
GtkSizeGroupMode orientation,
gint for_size,
CachedSize **result)
{
SizeRequestCache *cache;
SizeRequest **cached_sizes;
guint i, n_sizes;
cache = init_cache (widget);
if (for_size < 0)
{
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
*result = &cache->cached_width;
return cache->cached_base_width;
}
else
{
*result = &cache->cached_height;
return cache->cached_base_height;
}
}
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
cached_sizes = cache->widths;
n_sizes = cache->cached_widths;
}
else
{
cached_sizes = cache->heights;
n_sizes = cache->cached_heights;
}
/* Search for an already cached size */
for (i = 0; i < n_sizes; i++)
{
if (cached_sizes[i]->lower_for_size <= for_size &&
cached_sizes[i]->upper_for_size >= for_size)
{
*result = &cached_sizes[i]->cached_size;
return TRUE;
}
}
return FALSE;
}
static void
commit_cached_size (GtkWidget *widget,
GtkSizeGroupMode orientation,
gint for_size,
gint minimum_size,
gint natural_size)
{
SizeRequestCache *cache;
SizeRequest **cached_sizes;
guint i, n_sizes;
cache = _gtk_widget_peek_request_cache (widget);
/* First handle caching of the base requests */
if (for_size < 0)
{
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
cache->cached_width.minimum_size = minimum_size;
cache->cached_width.natural_size = natural_size;
cache->cached_base_width = TRUE;
}
else
{
cache->cached_height.minimum_size = minimum_size;
cache->cached_height.natural_size = natural_size;
cache->cached_base_height = TRUE;
}
return;
}
/* Check if the minimum_size and natural_size is already
* in the cache and if this result can be used to extend
* that cache entry
*/
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
cached_sizes = cache->widths;
n_sizes = cache->cached_widths;
}
else
{
cached_sizes = cache->heights;
n_sizes = cache->cached_heights;
}
for (i = 0; i < n_sizes; i++)
{
if (cached_sizes[i]->cached_size.minimum_size == minimum_size &&
cached_sizes[i]->cached_size.natural_size == natural_size)
{
cached_sizes[i]->lower_for_size = MIN (cached_sizes[i]->lower_for_size, for_size);
cached_sizes[i]->upper_for_size = MAX (cached_sizes[i]->upper_for_size, for_size);
return;
}
}
/* If not found, pull a new size from the cache, the returned size cache
* will immediately be used to cache the new computed size so we go ahead
* and increment the last_cached_width/height right away */
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
{
cache->cached_widths++;
cache->last_cached_width = cache->cached_widths - 1;
}
else
{
if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
cache->last_cached_width = 0;
}
if (!cache->widths)
cache->widths = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
if (!cache->widths[cache->last_cached_width])
cache->widths[cache->last_cached_width] = g_slice_new (SizeRequest);
cache->widths[cache->last_cached_width]->lower_for_size = for_size;
cache->widths[cache->last_cached_width]->upper_for_size = for_size;
cache->widths[cache->last_cached_width]->cached_size.minimum_size = minimum_size;
cache->widths[cache->last_cached_width]->cached_size.natural_size = natural_size;
}
else /* GTK_SIZE_GROUP_VERTICAL */
{
if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
{
cache->cached_heights++;
cache->last_cached_height = cache->cached_heights - 1;
}
else
{
if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
cache->last_cached_height = 0;
}
if (!cache->heights)
cache->heights = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
if (!cache->heights[cache->last_cached_height])
cache->heights[cache->last_cached_height] = g_slice_new (SizeRequest);
cache->heights[cache->last_cached_height]->lower_for_size = for_size;
cache->heights[cache->last_cached_height]->upper_for_size = for_size;
cache->heights[cache->last_cached_height]->cached_size.minimum_size = minimum_size;
cache->heights[cache->last_cached_height]->cached_size.natural_size = natural_size;
}
}
/* This is the main function that checks for a cached size and
* possibly queries the widget class to compute the size if it's
* not cached. If the for_size here is -1, then get_preferred_width()
* or get_preferred_height() will be used.
*/
static void
compute_size_for_orientation (GtkWidget *widget,
GtkSizeGroupMode orientation,
gint for_size,
gint *minimum_size,
gint *natural_size)
{
CachedSize *cached_size;
gboolean found_in_cache = FALSE;
gint min_size = 0;
gint nat_size = 0;
found_in_cache = get_cached_size (widget, orientation, for_size, &cached_size);
if (!found_in_cache)
{
gint adjusted_min, adjusted_natural, adjusted_for_size = for_size;
gtk_widget_ensure_style (widget);
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
{
if (for_size < 0)
{
push_recursion_check (widget, orientation, for_size);
GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
pop_recursion_check (widget, orientation);
}
else
{
gint ignored_position = 0;
gint minimum_height;
gint natural_height;
/* Pull the base natural height from the cache as it's needed to adjust
* the proposed 'for_size' */
gtk_widget_get_preferred_height (widget, &minimum_height, &natural_height);
/* convert for_size to unadjusted height (for_size is a proposed allocation) */
GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
GTK_ORIENTATION_VERTICAL,
&minimum_height,
&natural_height,
&ignored_position,
&adjusted_for_size);
push_recursion_check (widget, orientation, for_size);
GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget,
MAX (adjusted_for_size, minimum_height),
&min_size, &nat_size);
pop_recursion_check (widget, orientation);
}
}
else
{
if (for_size < 0)
{
push_recursion_check (widget, orientation, for_size);
GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
pop_recursion_check (widget, orientation);
}
else
{
gint ignored_position = 0;
gint minimum_width;
gint natural_width;
/* Pull the base natural width from the cache as it's needed to adjust
* the proposed 'for_size' */
gtk_widget_get_preferred_width (widget, &minimum_width, &natural_width);
/* convert for_size to unadjusted width (for_size is a proposed allocation) */
GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
GTK_ORIENTATION_HORIZONTAL,
&minimum_width,
&natural_width,
&ignored_position,
&adjusted_for_size);
push_recursion_check (widget, orientation, for_size);
GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget,
MAX (adjusted_for_size, minimum_width),
&min_size, &nat_size);
pop_recursion_check (widget, orientation);
}
}
if (min_size > nat_size)
{
g_warning ("%s %p reported min size %d and natural size %d; natural size must be >= min size",
G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size);
}
if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
_gtk_widget_set_width_request_needed (widget, FALSE);
else
_gtk_widget_set_height_request_needed (widget, FALSE);
adjusted_min = min_size;
adjusted_natural = nat_size;
GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
orientation == GTK_SIZE_GROUP_HORIZONTAL ?
GTK_ORIENTATION_HORIZONTAL :
GTK_ORIENTATION_VERTICAL,
&adjusted_min,
&adjusted_natural);
if (adjusted_min < min_size ||
adjusted_natural < nat_size)
{
g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
G_OBJECT_TYPE_NAME (widget), widget,
orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
adjusted_min, adjusted_natural,
min_size, nat_size);
/* don't use the adjustment */
}
else if (adjusted_min > adjusted_natural)
{
g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
G_OBJECT_TYPE_NAME (widget), widget,
orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
adjusted_min, adjusted_natural,
min_size, nat_size);
/* don't use the adjustment */
}
else
{
/* adjustment looks good */
min_size = adjusted_min;
nat_size = adjusted_natural;
}
/* Update size-groups with our request and update our cached requests
* with the size-group values in a single pass.
*/
_gtk_size_group_bump_requisition (widget,
orientation,
&min_size,
&nat_size);
commit_cached_size (widget, orientation, for_size, min_size, nat_size);
}
else
{
min_size = cached_size->minimum_size;
nat_size = cached_size->natural_size;
}
if (minimum_size)
*minimum_size = min_size;
if (natural_size)
*natural_size = nat_size;
g_assert (min_size <= nat_size);
GTK_NOTE (SIZE_REQUEST,
g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
widget, G_OBJECT_TYPE_NAME (widget),
orientation == GTK_SIZE_GROUP_HORIZONTAL ?
"width for height" : "height for width" ,
for_size, min_size, nat_size,
found_in_cache ? "yes" : "no"));
}
/**
* gtk_widget_get_request_mode:
* @widget: a #GtkWidget instance
*
* Gets whether the widget prefers a height-for-width layout
* or a width-for-height layout.
*
* <note><para>#GtkBin widgets generally propagate the preference of
* their child, container widgets need to request something either in
* context of their children or in context of their allocation
* capabilities.</para></note>
*
* Returns: The #GtkSizeRequestMode preferred by @widget.
*
* Since: 3.0
*/
GtkSizeRequestMode
gtk_widget_get_request_mode (GtkWidget *widget)
{
g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_CONSTANT_SIZE);
return GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget);
}
/**
* gtk_widget_get_preferred_width:
* @widget: a #GtkWidget instance
* @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
* @natural_width: (out) (allow-none): location to store the natural width, or %NULL
*
* Retrieves a widget's initial minimum and natural width.
*
* <note><para>This call is specific to height-for-width
* requests.</para></note>
*
* The returned request will be modified by the
* GtkWidgetClass::adjust_size_request virtual method and by any
* #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
* is the one that should be used for layout, not necessarily the one
* returned by the widget itself.
*
* Since: 3.0
*/
void
gtk_widget_get_preferred_width (GtkWidget *widget,
gint *minimum_width,
gint *natural_width)
{
g_return_if_fail (GTK_IS_WIDGET (widget));
g_return_if_fail (minimum_width != NULL || natural_width != NULL);
compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
-1, minimum_width, natural_width);
}
/**
* gtk_widget_get_preferred_height:
* @widget: a #GtkWidget instance
* @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
* @natural_height: (out) (allow-none): location to store the natural height, or %NULL
*
* Retrieves a widget's initial minimum and natural height.
*
* <note><para>This call is specific to width-for-height requests.</para></note>
*
* The returned request will be modified by the
* GtkWidgetClass::adjust_size_request virtual method and by any
* #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
* is the one that should be used for layout, not necessarily the one
* returned by the widget itself.
*
* Since: 3.0
*/
void
gtk_widget_get_preferred_height (GtkWidget *widget,
gint *minimum_height,
gint *natural_height)
{
g_return_if_fail (GTK_IS_WIDGET (widget));
g_return_if_fail (minimum_height != NULL || natural_height != NULL);
compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
-1, minimum_height, natural_height);
}
/**
* gtk_widget_get_preferred_width_for_height:
* @widget: a #GtkWidget instance
* @height: the height which is available for allocation
* @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
* @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
*
* Retrieves a widget's minimum and natural width if it would be given
* the specified @height.
*
* The returned request will be modified by the
* GtkWidgetClass::adjust_size_request virtual method and by any
* #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
* is the one that should be used for layout, not necessarily the one
* returned by the widget itself.
*
* Since: 3.0
*/
void
gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
gint height,
gint *minimum_width,
gint *natural_width)
{
g_return_if_fail (GTK_IS_WIDGET (widget));
g_return_if_fail (minimum_width != NULL || natural_width != NULL);
g_return_if_fail (height >= 0);
if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
-1, minimum_width, natural_width);
else
compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
height, minimum_width, natural_width);
}
/**
* gtk_widget_get_preferred_height_for_width:
* @widget: a #GtkWidget instance
* @width: the width which is available for allocation
* @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
* @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
*
* Retrieves a widget's minimum and natural height if it would be given
* the specified @width.
*
* The returned request will be modified by the
* GtkWidgetClass::adjust_size_request virtual method and by any
* #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
* is the one that should be used for layout, not necessarily the one
* returned by the widget itself.
*
* Since: 3.0
*/
void
gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
gint width,
gint *minimum_height,
gint *natural_height)
{
g_return_if_fail (GTK_IS_WIDGET (widget));
g_return_if_fail (minimum_height != NULL || natural_height != NULL);
g_return_if_fail (width >= 0);
if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
-1, minimum_height, natural_height);
else
compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
width, minimum_height, natural_height);
}
/**
* gtk_widget_get_preferred_size:
* @widget: a #GtkWidget instance
* @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
* @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
*
* Retrieves the minimum and natural size of a widget, taking
* into account the widget's preference for height-for-width management.
*
* This is used to retrieve a suitable size by container widgets which do
* not impose any restrictions on the child placement. It can be used
* to deduce toplevel window and menu sizes as well as child widgets in
* free-form containers such as GtkLayout.
*
* <note><para>Handle with care. Note that the natural height of a height-for-width
* widget will generally be a smaller size than the minimum height, since the required
* height for the natural width is generally smaller than the required height for
* the minimum width.</para></note>
*
* Since: 3.0
*/
void
gtk_widget_get_preferred_size (GtkWidget *widget,
GtkRequisition *minimum_size,
GtkRequisition *natural_size)
{
gint min_width, nat_width;
gint min_height, nat_height;
g_return_if_fail (GTK_IS_WIDGET (widget));
if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
{
gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
if (minimum_size)
{
minimum_size->width = min_width;
gtk_widget_get_preferred_height_for_width (widget, min_width,
&minimum_size->height, NULL);
}
if (natural_size)
{
natural_size->width = nat_width;
gtk_widget_get_preferred_height_for_width (widget, nat_width,
NULL, &natural_size->height);
}
}
else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT or CONSTANT_SIZE */
{
gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
if (minimum_size)
{
minimum_size->height = min_height;
gtk_widget_get_preferred_width_for_height (widget, min_height,
&minimum_size->width, NULL);
}
if (natural_size)
{
natural_size->height = nat_height;
gtk_widget_get_preferred_width_for_height (widget, nat_height,
NULL, &natural_size->width);
}
}
}
static gint
compare_gap (gconstpointer p1,
gconstpointer p2,
gpointer data)
{
GtkRequestedSize *sizes = data;
const guint *c1 = p1;
const guint *c2 = p2;
const gint d1 = MAX (sizes[*c1].natural_size -
sizes[*c1].minimum_size,
0);
const gint d2 = MAX (sizes[*c2].natural_size -
sizes[*c2].minimum_size,
0);
gint delta = (d2 - d1);
if (0 == delta)
delta = (*c2 - *c1);
return delta;
}
/**
* gtk_distribute_natural_allocation:
* @extra_space: Extra space to redistribute among children after subtracting
* minimum sizes and any child padding from the overall allocation
* @n_requested_sizes: Number of requests to fit into the allocation
* @sizes: An array of structs with a client pointer and a minimum/natural size
* in the orientation of the allocation.
*
* Distributes @extra_space to child @sizes by bringing smaller
* children up to natural size first.
*
* The remaining space will be added to the @minimum_size member of the
* GtkRequestedSize struct. If all sizes reach their natural size then
* the remaining space is returned.
*
* Returns: The remainder of @extra_space after redistributing space
* to @sizes.
*/
gint
gtk_distribute_natural_allocation (gint extra_space,
guint n_requested_sizes,
GtkRequestedSize *sizes)
{
guint *spreading;
gint i;
g_return_val_if_fail (extra_space >= 0, 0);
spreading = g_newa (guint, n_requested_sizes);
for (i = 0; i < n_requested_sizes; i++)
spreading[i] = i;
/* Distribute the container's extra space c_gap. We want to assign
* this space such that the sum of extra space assigned to children
* (c^i_gap) is equal to c_cap. The case that there's not enough
* space for all children to take their natural size needs some
* attention. The goals we want to achieve are:
*
* a) Maximize number of children taking their natural size.
* b) The allocated size of children should be a continuous
* function of c_gap. That is, increasing the container size by
* one pixel should never make drastic changes in the distribution.
* c) If child i takes its natural size and child j doesn't,
* child j should have received at least as much gap as child i.
*
* The following code distributes the additional space by following
* these rules.
*/
/* Sort descending by gap and position. */
g_qsort_with_data (spreading,
n_requested_sizes, sizeof (guint),
compare_gap, sizes);
/* Distribute available space.
* This master piece of a loop was conceived by Behdad Esfahbod.
*/
for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
{
/* Divide remaining space by number of remaining children.
* Sort order and reducing remaining space by assigned space
* ensures that space is distributed equally.
*/
gint glue = (extra_space + i) / (i + 1);
gint gap = sizes[(spreading[i])].natural_size
- sizes[(spreading[i])].minimum_size;
gint extra = MIN (glue, gap);
sizes[spreading[i]].minimum_size += extra;
extra_space -= extra;
}
return extra_space;
}
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