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, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
25 #include "gtksizerequest.h"
26 #include "gtksizegroup.h"
28 #include "gtkprivate.h"
31 /* looks for a cached size request for this for_size. If not
32 * found, returns the oldest entry so it can be overwritten
34 * Note that this caching code was directly derived from
35 * the Clutter toolkit.
38 get_cached_size (SizeRequestCache *cache,
39 GtkSizeGroupMode orientation,
44 SizeRequest *cached_sizes;
46 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
48 cached_sizes = cache->widths;
49 n_sizes = cache->cached_widths;
53 cached_sizes = cache->heights;
54 n_sizes = cache->cached_widths;
57 /* Search for an already cached size */
58 for (i = 0; i < n_sizes; i++)
60 if (cached_sizes[i].for_size == for_size)
62 *result = &cached_sizes[i];
67 /* If not found, pull a new size from the cache, the returned size cache
68 * will immediately be used to cache the new computed size so we go ahead
69 * and increment the last_cached_width/height right away */
70 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
72 if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
74 cache->cached_widths++;
75 cache->last_cached_width = cache->cached_widths - 1;
79 if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
80 cache->last_cached_width = 0;
83 *result = &cache->widths[cache->last_cached_width];
85 else /* GTK_SIZE_GROUP_VERTICAL */
87 if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
89 cache->cached_heights++;
90 cache->last_cached_height = cache->cached_heights - 1;
94 if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
95 cache->last_cached_height = 0;
98 *result = &cache->heights[cache->last_cached_height];
105 do_size_request (GtkWidget *widget,
106 GtkRequisition *requisition)
108 /* Now we dont bother caching the deprecated "size-request" returns,
109 * just unconditionally invoke here just in case we run into legacy stuff */
110 gtk_widget_ensure_style (widget);
111 g_signal_emit_by_name (widget, "size-request", requisition);
114 #ifndef G_DISABLE_CHECKS
115 static GQuark recursion_check_quark = 0;
116 #endif /* G_DISABLE_CHECKS */
119 push_recursion_check (GtkWidget *request,
120 GtkSizeGroupMode orientation,
123 #ifndef G_DISABLE_CHECKS
124 const char *previous_method;
127 if (recursion_check_quark == 0)
128 recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
130 previous_method = g_object_get_qdata (G_OBJECT (request), recursion_check_quark);
132 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
134 method = for_size < 0 ? "get_width" : "get_width_for_height";
138 method = for_size < 0 ? "get_height" : "get_height_for_width";
141 if (previous_method != NULL)
143 g_warning ("%s %p: widget tried to gtk_widget_%s inside "
144 " GtkWidget ::%s implementation. "
145 "Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
146 "directly rather than using gtk_widget_%s",
147 G_OBJECT_TYPE_NAME (request), request,
148 method, previous_method,
152 g_object_set_qdata (G_OBJECT (request), recursion_check_quark, (char*) method);
153 #endif /* G_DISABLE_CHECKS */
157 pop_recursion_check (GtkWidget *request,
158 GtkSizeGroupMode orientation)
160 #ifndef G_DISABLE_CHECKS
161 g_object_set_qdata (G_OBJECT (request), recursion_check_quark, NULL);
166 compute_size_for_orientation (GtkWidget *request,
167 GtkSizeGroupMode orientation,
172 SizeRequestCache *cache;
173 SizeRequest *cached_size;
175 gboolean found_in_cache = FALSE;
176 int adjusted_min, adjusted_natural;
178 g_return_if_fail (GTK_IS_WIDGET (request));
179 g_return_if_fail (minimum_size != NULL || natural_size != NULL);
181 widget = GTK_WIDGET (request);
182 cache = _gtk_widget_peek_request_cache (widget);
184 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
186 cached_size = &cache->widths[0];
188 if (!_gtk_widget_get_width_request_needed (widget))
189 found_in_cache = get_cached_size (cache, orientation, for_size, &cached_size);
192 memset (cache->widths, 0, GTK_SIZE_REQUEST_CACHED_SIZES * sizeof (SizeRequest));
193 cache->cached_widths = 1;
194 cache->last_cached_width = 0;
199 cached_size = &cache->heights[0];
201 if (!_gtk_widget_get_height_request_needed (widget))
202 found_in_cache = get_cached_size (cache, orientation, for_size, &cached_size);
205 memset (cache->heights, 0, GTK_SIZE_REQUEST_CACHED_SIZES * sizeof (SizeRequest));
206 cache->cached_heights = 1;
207 cache->last_cached_height = 0;
213 GtkRequisition requisition = { 0, 0 };
214 gint min_size = 0, nat_size = 0;
215 gint requisition_size;
217 /* Unconditional size request runs but is often unhandled. */
218 do_size_request (widget, &requisition);
220 push_recursion_check (request, orientation, for_size);
221 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
223 requisition_size = requisition.width;
226 GTK_WIDGET_GET_CLASS (request)->get_preferred_width (request, &min_size, &nat_size);
228 GTK_WIDGET_GET_CLASS (request)->get_preferred_width_for_height (request, for_size,
229 &min_size, &nat_size);
233 requisition_size = requisition.height;
236 GTK_WIDGET_GET_CLASS (request)->get_preferred_height (request, &min_size, &nat_size);
238 GTK_WIDGET_GET_CLASS (request)->get_preferred_height_for_width (request, for_size,
239 &min_size, &nat_size);
241 pop_recursion_check (request, orientation);
243 if (min_size > nat_size)
245 g_warning ("%s %p reported min size %d and natural size %d; natural size must be >= min size",
246 G_OBJECT_TYPE_NAME (request), request, min_size, nat_size);
249 /* Support for dangling "size-request" signal implementations on
252 min_size = MAX (min_size, requisition_size);
253 nat_size = MAX (nat_size, requisition_size);
255 cached_size->minimum_size = min_size;
256 cached_size->natural_size = nat_size;
257 cached_size->for_size = for_size;
259 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
260 _gtk_widget_set_width_request_needed (widget, FALSE);
262 _gtk_widget_set_height_request_needed (widget, FALSE);
264 adjusted_min = cached_size->minimum_size;
265 adjusted_natural = cached_size->natural_size;
266 GTK_WIDGET_GET_CLASS (request)->adjust_size_request (GTK_WIDGET (request),
267 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
268 GTK_ORIENTATION_HORIZONTAL :
269 GTK_ORIENTATION_VERTICAL,
270 cached_size->for_size,
274 if (adjusted_min < cached_size->minimum_size ||
275 adjusted_natural < cached_size->natural_size)
277 g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
278 G_OBJECT_TYPE_NAME (request), request,
279 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
280 adjusted_min, adjusted_natural,
281 cached_size->minimum_size, cached_size->natural_size);
282 /* don't use the adjustment */
284 else if (adjusted_min > adjusted_natural)
286 g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
287 G_OBJECT_TYPE_NAME (request), request,
288 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
289 adjusted_min, adjusted_natural,
290 cached_size->minimum_size, cached_size->natural_size);
291 /* don't use the adjustment */
295 /* adjustment looks good */
296 cached_size->minimum_size = adjusted_min;
297 cached_size->natural_size = adjusted_natural;
300 /* Update size-groups with our request and update our cached requests
301 * with the size-group values in a single pass.
303 _gtk_size_group_bump_requisition (GTK_WIDGET (request),
305 &cached_size->minimum_size,
306 &cached_size->natural_size);
310 *minimum_size = cached_size->minimum_size;
313 *natural_size = cached_size->natural_size;
315 g_assert (cached_size->minimum_size <= cached_size->natural_size);
317 GTK_NOTE (SIZE_REQUEST,
318 g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
319 request, G_OBJECT_TYPE_NAME (request),
320 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
321 "width for height" : "height for width" ,
323 cached_size->minimum_size,
324 cached_size->natural_size,
325 found_in_cache ? "yes" : "no"));
330 * gtk_widget_get_request_mode:
331 * @widget: a #GtkWidget instance
333 * Gets whether the widget prefers a height-for-width layout
334 * or a width-for-height layout.
336 * <note><para>#GtkBin widgets generally propagate the preference of
337 * their child, container widgets need to request something either in
338 * context of their children or in context of their allocation
339 * capabilities.</para></note>
341 * Returns: The #GtkSizeRequestMode preferred by @widget.
346 gtk_widget_get_request_mode (GtkWidget *widget)
348 GtkWidgetClass *klass;
350 g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH);
352 klass = GTK_WIDGET_GET_CLASS (widget);
353 if (klass->get_request_mode)
354 return klass->get_request_mode (widget);
356 /* By default widgets are height-for-width. */
357 return GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH;
361 * gtk_widget_get_preferred_width:
362 * @widget: a #GtkWidget instance
363 * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
364 * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
366 * Retrieves a widget's initial minimum and natural width.
368 * <note><para>This call is specific to height-for-width
369 * requests.</para></note>
371 * The returned request will be modified by the
372 * GtkWidgetClass::adjust_size_request virtual method and by any
373 * #GtkSizeGroup that have been applied. That is, the returned request
374 * is the one that should be used for layout, not necessarily the one
375 * returned by the widget itself.
380 gtk_widget_get_preferred_width (GtkWidget *widget,
384 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
385 -1, minimum_width, natural_width);
390 * gtk_widget_get_preferred_height:
391 * @widget: a #GtkWidget instance
392 * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
393 * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
395 * Retrieves a widget's initial minimum and natural height.
397 * <note><para>This call is specific to width-for-height requests.</para></note>
399 * The returned request will be modified by the
400 * GtkWidgetClass::adjust_size_request virtual method and by any
401 * #GtkSizeGroup that have been applied. That is, the returned request
402 * is the one that should be used for layout, not necessarily the one
403 * returned by the widget itself.
408 gtk_widget_get_preferred_height (GtkWidget *widget,
409 gint *minimum_height,
410 gint *natural_height)
412 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
413 -1, minimum_height, natural_height);
419 * gtk_widget_get_preferred_width_for_height:
420 * @widget: a #GtkWidget instance
421 * @height: the height which is available for allocation
422 * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
423 * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
425 * Retrieves a widget's minimum and natural width if it would be given
426 * the specified @height.
428 * The returned request will be modified by the
429 * GtkWidgetClass::adjust_size_request virtual method and by any
430 * #GtkSizeGroup that have been applied. That is, the returned request
431 * is the one that should be used for layout, not necessarily the one
432 * returned by the widget itself.
437 gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
442 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
443 height, minimum_width, natural_width);
447 * gtk_widget_get_preferred_height_for_width:
448 * @widget: a #GtkWidget instance
449 * @width: the width which is available for allocation
450 * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
451 * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
453 * Retrieves a widget's minimum and natural height if it would be given
454 * the specified @width.
456 * The returned request will be modified by the
457 * GtkWidgetClass::adjust_size_request virtual method and by any
458 * #GtkSizeGroup that have been applied. That is, the returned request
459 * is the one that should be used for layout, not necessarily the one
460 * returned by the widget itself.
465 gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
467 gint *minimum_height,
468 gint *natural_height)
470 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
471 width, minimum_height, natural_height);
475 * gtk_widget_get_preferred_size:
476 * @widget: a #GtkWidget instance
477 * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
478 * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
480 * Retrieves the minimum and natural size of a widget taking
481 * into account the widget's preference for height-for-width management.
483 * This is used to retrieve a suitable size by container widgets which do
484 * not impose any restrictions on the child placement. It can be used
485 * to deduce toplevel window and menu sizes as well as child widgets in
486 * free form containers such as GtkLayout.
488 * <note><para>Handle with care, note that the natural height of a height-for-width
489 * widget will generally be a smaller size than the minimum height, since the required
490 * height for the natural width is generally smaller than the required height for
491 * the minimum width.</para></note>
496 gtk_widget_get_preferred_size (GtkWidget *widget,
497 GtkRequisition *minimum_size,
498 GtkRequisition *natural_size)
500 gint min_width, nat_width;
501 gint min_height, nat_height;
503 g_return_if_fail (GTK_IS_WIDGET (widget));
505 if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
507 gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
511 minimum_size->width = min_width;
512 gtk_widget_get_preferred_height_for_width (widget, min_width,
513 &minimum_size->height, NULL);
518 natural_size->width = nat_width;
519 gtk_widget_get_preferred_height_for_width (widget, nat_width,
520 NULL, &natural_size->height);
523 else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT */
525 gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
529 minimum_size->height = min_height;
530 gtk_widget_get_preferred_width_for_height (widget, min_height,
531 &minimum_size->width, NULL);
536 natural_size->height = nat_height;
537 gtk_widget_get_preferred_width_for_height (widget, nat_height,
538 NULL, &natural_size->width);
545 compare_gap (gconstpointer p1,
549 GtkRequestedSize *sizes = data;
550 const guint *c1 = p1;
551 const guint *c2 = p2;
553 const gint d1 = MAX (sizes[*c1].natural_size -
554 sizes[*c1].minimum_size,
556 const gint d2 = MAX (sizes[*c2].natural_size -
557 sizes[*c2].minimum_size,
560 gint delta = (d2 - d1);
569 * gtk_distribute_natural_allocation:
570 * @extra_space: Extra space to redistribute among children after subtracting
571 * minimum sizes and any child padding from the overall allocation
572 * @n_requested_sizes: Number of requests to fit into the allocation
573 * @sizes: An array of structs with a client pointer and a minimum/natural size
574 * in the orientation of the allocation.
576 * Distributes @extra_space to child @sizes by bringing up smaller
577 * children up to natural size first.
579 * The remaining space will be added to the @minimum_size member of the
580 * GtkRequestedSize struct. If all sizes reach their natural size then
581 * the remaining space is returned.
583 * Returns: The remainder of @extra_space after redistributing space
587 gtk_distribute_natural_allocation (gint extra_space,
588 guint n_requested_sizes,
589 GtkRequestedSize *sizes)
594 g_return_val_if_fail (extra_space >= 0, 0);
596 spreading = g_newa (guint, n_requested_sizes);
598 for (i = 0; i < n_requested_sizes; i++)
601 /* Distribute the container's extra space c_gap. We want to assign
602 * this space such that the sum of extra space assigned to children
603 * (c^i_gap) is equal to c_cap. The case that there's not enough
604 * space for all children to take their natural size needs some
605 * attention. The goals we want to achieve are:
607 * a) Maximize number of children taking their natural size.
608 * b) The allocated size of children should be a continuous
609 * function of c_gap. That is, increasing the container size by
610 * one pixel should never make drastic changes in the distribution.
611 * c) If child i takes its natural size and child j doesn't,
612 * child j should have received at least as much gap as child i.
614 * The following code distributes the additional space by following
618 /* Sort descending by gap and position. */
619 g_qsort_with_data (spreading,
620 n_requested_sizes, sizeof (guint),
623 /* Distribute available space.
624 * This master piece of a loop was conceived by Behdad Esfahbod.
626 for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
628 /* Divide remaining space by number of remaining children.
629 * Sort order and reducing remaining space by assigned space
630 * ensures that space is distributed equally.
632 gint glue = (extra_space + i) / (i + 1);
633 gint gap = sizes[(spreading[i])].natural_size
634 - sizes[(spreading[i])].minimum_size;
636 gint extra = MIN (glue, gap);
638 sizes[spreading[i]].minimum_size += extra;
640 extra_space -= extra;