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689905c1b4
gtk2/gtk/gtksizerequest.c
Benjamin Otte 689905c1b4 widget: make gtk_widget_compute_size_for_orientation() static 
It's not used anywhere outside of gtksizerequest.c anymore.
2013-05-11 15:11:53 +02:00

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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, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include "gtksizerequest.h"
#include "gtkdebug.h"
#include "gtkintl.h"
#include "gtkprivate.h"
#include "gtksizegroup-private.h"
#include "gtksizerequestcacheprivate.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,
GtkOrientation 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_ORIENTATION_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,
GtkOrientation orientation)
{
#ifndef G_DISABLE_CHECKS
g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
#endif
}
static const char *
get_vfunc_name (GtkOrientation orientation,
gint for_size)
{
if (orientation == GTK_ORIENTATION_HORIZONTAL)
return for_size < 0 ? "get_preferred_width" : "get_preferred_width_for_height";
else
return for_size < 0 ? "get_preferred_height" : "get_preferred_height_for_width";
}
static gboolean
widget_class_has_baseline_support (GtkWidgetClass *widget_class)
{
GtkWidgetClass *parent_class;
if (widget_class->get_preferred_height_and_baseline_for_width == NULL)
return FALSE;
/* This is kinda hacky, but for backwards compatibility reasons we have to handle the case
where a class previously did not support get_preferred_height_and_baseline_for_width,
but then gained support for it, and a subclass of it overrides the previous non-baseline
methods. If this happens we need to call the overridden (non-baseline supporting) versions
on the subclass, rather than the inherited but not overriddent new get_preferred_height_and_baseline_for_width.
*/
/* Loop over all parent classes that inherit the same get_preferred_height_and_baseline_for_width */
parent_class = g_type_class_peek_parent (widget_class);
while (parent_class != NULL &&
parent_class->get_preferred_height_and_baseline_for_width == widget_class->get_preferred_height_and_baseline_for_width)
{
if (parent_class->get_preferred_height != widget_class->get_preferred_height ||
parent_class->get_preferred_height_for_width != widget_class->get_preferred_height_for_width)
return FALSE;
parent_class = g_type_class_peek_parent (parent_class);
}
return TRUE;
}
gboolean
_gtk_widget_has_baseline_support (GtkWidget *widget)
{
GtkWidgetClass *widget_class;
widget_class = GTK_WIDGET_GET_CLASS (widget);
return widget_class_has_baseline_support (widget_class);
}
static void
gtk_widget_query_size_for_orientation (GtkWidget *widget,
GtkOrientation orientation,
gint for_size,
gint *minimum_size,
gint *natural_size,
gint *minimum_baseline,
gint *natural_baseline)
{
SizeRequestCache *cache;
GtkWidgetClass *widget_class;
gint min_size = 0;
gint nat_size = 0;
gint min_baseline = -1;
gint nat_baseline = -1;
gboolean found_in_cache;
if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
for_size = -1;
cache = _gtk_widget_peek_request_cache (widget);
found_in_cache = _gtk_size_request_cache_lookup (cache,
orientation,
for_size,
&min_size,
&nat_size,
&min_baseline,
&nat_baseline);
widget_class = GTK_WIDGET_GET_CLASS (widget);
if (!found_in_cache)
{
gint adjusted_min, adjusted_natural, adjusted_for_size = for_size;
G_GNUC_BEGIN_IGNORE_DEPRECATIONS;
gtk_widget_ensure_style (widget);
G_GNUC_END_IGNORE_DEPRECATIONS;
if (orientation == GTK_ORIENTATION_HORIZONTAL)
{
if (for_size < 0)
{
push_recursion_check (widget, orientation, for_size);
widget_class->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) */
widget_class->adjust_size_allocation (widget,
GTK_ORIENTATION_VERTICAL,
&minimum_height,
&natural_height,
&ignored_position,
&adjusted_for_size);
push_recursion_check (widget, orientation, for_size);
widget_class->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);
if (widget_class_has_baseline_support (widget_class))
widget_class->get_preferred_height_and_baseline_for_width (widget, -1,
&min_size, &nat_size,
&min_baseline, &nat_baseline);
else
widget_class->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) */
widget_class->adjust_size_allocation (widget,
GTK_ORIENTATION_HORIZONTAL,
&minimum_width,
&natural_width,
&ignored_position,
&adjusted_for_size);
push_recursion_check (widget, orientation, for_size);
if (widget_class_has_baseline_support (widget_class))
widget_class->get_preferred_height_and_baseline_for_width (widget, MAX (adjusted_for_size, minimum_width),
&min_size, &nat_size,
&min_baseline, &nat_baseline);
else
widget_class->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 in %s(); natural size must be >= min size",
G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size, get_vfunc_name (orientation, for_size));
}
adjusted_min = min_size;
adjusted_natural = nat_size;
widget_class->adjust_size_request (widget,
orientation,
&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_ORIENTATION_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_ORIENTATION_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;
}
if (min_baseline != -1 || nat_baseline != -1)
{
if (orientation == GTK_ORIENTATION_HORIZONTAL)
{
g_warning ("%s %p reported a horizontal baseline",
G_OBJECT_TYPE_NAME (widget), widget);
min_baseline = -1;
nat_baseline = -1;
}
else if (min_baseline == -1 || nat_baseline == -1)
{
g_warning ("%s %p reported baseline for only one of min/natural (min: %d, natural: %d)",
G_OBJECT_TYPE_NAME (widget), widget,
min_baseline, nat_baseline);
min_baseline = -1;
nat_baseline = -1;
}
else if (gtk_widget_get_valign_with_baseline (widget) != GTK_ALIGN_BASELINE)
{
/* Ignore requested baseline for non-aligned widgets */
min_baseline = -1;
nat_baseline = -1;
}
else
widget_class->adjust_baseline_request (widget,
&min_baseline,
&nat_baseline);
}
_gtk_size_request_cache_commit (cache,
orientation,
for_size,
min_size,
nat_size,
min_baseline,
nat_baseline);
}
if (minimum_size)
*minimum_size = min_size;
if (natural_size)
*natural_size = nat_size;
if (minimum_baseline)
*minimum_baseline = min_baseline;
if (natural_baseline)
*natural_baseline = nat_baseline;
g_assert (min_size <= nat_size);
GTK_NOTE (SIZE_REQUEST,
g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d",
widget, G_OBJECT_TYPE_NAME (widget),
orientation == GTK_ORIENTATION_HORIZONTAL ?
"width for height" : "height for width" ,
for_size, min_size, nat_size);
if (min_baseline != -1 || nat_baseline != -1)
g_print (", baseline %d/%d",
min_baseline, nat_baseline);
g_print (" (hit cache: %s)\n",
found_in_cache ? "yes" : "no")
);
}
/* 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
gtk_widget_compute_size_for_orientation (GtkWidget *widget,
GtkOrientation orientation,
gint for_size,
gint *minimum,
gint *natural,
gint *minimum_baseline,
gint *natural_baseline)
{
GHashTable *widgets;
GHashTableIter iter;
gpointer key;
gint min_result = 0, nat_result = 0;
if (!gtk_widget_get_visible (widget) && !gtk_widget_is_toplevel (widget))
{
if (minimum)
*minimum = 0;
if (natural)
*natural = 0;
if (minimum_baseline)
*minimum_baseline = -1;
if (natural_baseline)
*natural_baseline = -1;
return;
}
if (G_LIKELY (!_gtk_widget_get_sizegroups (widget)))
{
gtk_widget_query_size_for_orientation (widget, orientation, for_size, minimum, natural,
minimum_baseline, natural_baseline);
return;
}
widgets = _gtk_size_group_get_widget_peers (widget, orientation);
g_hash_table_foreach (widgets, (GHFunc) g_object_ref, NULL);
g_hash_table_iter_init (&iter, widgets);
while (g_hash_table_iter_next (&iter, &key, NULL))
{
GtkWidget *tmp_widget = key;
gint min_dimension, nat_dimension;
gtk_widget_query_size_for_orientation (tmp_widget, orientation, for_size, &min_dimension, &nat_dimension, NULL, NULL);
min_result = MAX (min_result, min_dimension);
nat_result = MAX (nat_result, nat_dimension);
}
g_hash_table_foreach (widgets, (GHFunc) g_object_unref, NULL);
g_hash_table_destroy (widgets);
/* Baselines make no sense with sizegroups really */
if (minimum_baseline)
*minimum_baseline = -1;
if (natural_baseline)
*natural_baseline = -1;
if (minimum)
*minimum = min_result;
if (natural)
*natural = nat_result;
}
/**
* 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)
{
SizeRequestCache *cache;
g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_CONSTANT_SIZE);
cache = _gtk_widget_peek_request_cache (widget);
if (!cache->request_mode_valid)
{
cache->request_mode = GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget);
cache->request_mode_valid = TRUE;
}
return cache->request_mode;
}
/**
* 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);
gtk_widget_compute_size_for_orientation (widget,
GTK_ORIENTATION_HORIZONTAL,
-1,
minimum_width,
natural_width,
NULL, NULL);
}
/**
* 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);
gtk_widget_compute_size_for_orientation (widget,
GTK_ORIENTATION_VERTICAL,
-1,
minimum_height,
natural_height,
NULL, NULL);
}
/**
* 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);
gtk_widget_compute_size_for_orientation (widget,
GTK_ORIENTATION_HORIZONTAL,
height,
minimum_width,
natural_width,
NULL, NULL);
}
/**
* 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);
gtk_widget_compute_size_for_orientation (widget,
GTK_ORIENTATION_VERTICAL,
width,
minimum_height,
natural_height,
NULL, NULL);
}
/**
* gtk_widget_get_preferred_height_and_baseline_for_width:
* @widget: a #GtkWidget instance
* @width: the width which is available for allocation, or -1 if none
* @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
* @minimum_baseline: (out) (allow-none): location for storing the baseline for the minimum height, or %NULL
* @natural_baseline: (out) (allow-none): location for storing the baseline for the natural height, or %NULL
*
* Retrieves a widget's minimum and natural height and the corresponding baselines if it would be given
* the specified @width, or the default height if @width is -1. The baselines may be -1 which means
* that no baseline is requested for this widget.
*
* The returned request will be modified by the
* GtkWidgetClass::adjust_size_request and GtkWidgetClass::adjust_baseline_request virtual methods
* 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: 3.10
*/
void
gtk_widget_get_preferred_height_and_baseline_for_width (GtkWidget *widget,
gint width,
gint *minimum_height,
gint *natural_height,
gint *minimum_baseline,
gint *natural_baseline)
{
g_return_if_fail (GTK_IS_WIDGET (widget));
g_return_if_fail (minimum_height != NULL || natural_height != NULL);
g_return_if_fail (width >= -1);
gtk_widget_compute_size_for_orientation (widget,
GTK_ORIENTATION_VERTICAL,
width,
minimum_height,
natural_height,
minimum_baseline,
natural_baseline);
}
/*
* _gtk_widget_get_preferred_size_and_baseline:
* @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 and the corresponding baselines of a widget, taking
* into account the widget's preference for height-for-width management. The baselines may
* be -1 which means that no baseline is requested for this widget.
*
* 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>
*/
void
_gtk_widget_get_preferred_size_and_baseline (GtkWidget *widget,
GtkRequisition *minimum_size,
GtkRequisition *natural_size,
gint *minimum_baseline,
gint *natural_baseline)
{
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_and_baseline_for_width (widget, min_width,
&minimum_size->height, NULL, minimum_baseline, NULL);
}
if (natural_size)
{
natural_size->width = nat_width;
gtk_widget_get_preferred_height_and_baseline_for_width (widget, nat_width,
NULL, &natural_size->height, NULL, natural_baseline);
}
}
else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT or CONSTANT_SIZE */
{
gtk_widget_get_preferred_height_and_baseline_for_width (widget, -1, &min_height, &nat_height, minimum_baseline, natural_baseline);
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);
}
}
}
/**
* 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>
*
* Use gtk_widget_get_preferred_size_and_baseline() if you want to support
* baseline alignment.
*
* Since: 3.0
*/
void
gtk_widget_get_preferred_size (GtkWidget *widget,
GtkRequisition *minimum_size,
GtkRequisition *natural_size)
{
_gtk_widget_get_preferred_size_and_baseline (widget, minimum_size, natural_size,
NULL, NULL);
}
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;
}
void
_gtk_widget_get_preferred_size_for_size (GtkWidget *widget,
GtkOrientation orientation,
gint size,
gint *minimum,
gint *natural,
gint *minimum_baseline,
gint *natural_baseline)
{
g_return_if_fail (GTK_IS_WIDGET (widget));
g_return_if_fail (size >= -1);
if (orientation == GTK_ORIENTATION_HORIZONTAL)
{
if (size < 0)
gtk_widget_get_preferred_width (widget, minimum, natural);
else
gtk_widget_get_preferred_width_for_height (widget, size, minimum, natural);
if (minimum_baseline)
*minimum_baseline = -1;
if (natural_baseline)
*natural_baseline = -1;
}
else
{
gtk_widget_get_preferred_height_and_baseline_for_width (widget,
size,
minimum,
natural,
minimum_baseline,
natural_baseline);
}
}
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