clutter/clutter-fixed-layout.c

   1 /*
   2  * Clutter.
   3  *
   4  * An OpenGL based 'interactive canvas' library.
   5  *
   6  * Copyright (C) 2009  Intel Corporation.
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser 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.
  12  *
  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  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library. If not, see <http://www.gnu.org/licenses/>.
  20  *
  21  * Author:
  22  *   Emmanuele Bassi <ebassi@linux.intel.com>
  23  *
  24  * Based on the fixed layout code inside clutter-group.c
  25  */
  26
  27 /**
  28  * SECTION:clutter-fixed-layout
  29  * @short_description: A fixed layout manager
  30  *
  31  * #ClutterFixedLayout is a layout manager implementing the same
  32  * layout policies as #ClutterGroup.
  33  *
  34  * #ClutterFixedLayout is available since Clutter 1.2
  35  */
  36
  37 #ifdef HAVE_CONFIG_H
  38 #include "config.h"
  39 #endif
  40
  41 #include "clutter-debug.h"
  42 #include "clutter-fixed-layout.h"
  43 #include "clutter-private.h"
  44
  45 G_DEFINE_TYPE (ClutterFixedLayout,
  46                clutter_fixed_layout,
  47                CLUTTER_TYPE_LAYOUT_MANAGER);
  48
  49 static void
  50 clutter_fixed_layout_get_preferred_width (ClutterLayoutManager *manager,
  51                                           ClutterContainer     *container,
  52                                           gfloat                for_height,
  53                                           gfloat               *min_width_p,
  54                                           gfloat               *nat_width_p)
  55 {
  56   ClutterActor *actor, *child;
  57   gdouble min_right;
  58   gdouble natural_right;
  59
  60   min_right = 0;
  61   natural_right = 0;
  62
  63   actor = CLUTTER_ACTOR (container);
  64
  65   for (child = clutter_actor_get_first_child (actor);
  66        child != NULL;
  67        child = clutter_actor_get_next_sibling (child))
  68     {
  69       gfloat child_x, child_min, child_natural;
  70
  71       child_x = clutter_actor_get_x (child);
  72
  73       clutter_actor_get_preferred_size (child,
  74                                         &child_min, NULL,
  75                                         &child_natural, NULL);
  76
  77       if (child_x + child_min > min_right)
  78         min_right = child_x + child_min;
  79
  80       if (child_x + child_natural > natural_right)
  81         natural_right = child_x + child_natural;
  82     }
  83
  84   if (min_width_p)
  85     *min_width_p = min_right;
  86
  87   if (nat_width_p)
  88     *nat_width_p = natural_right;
  89 }
  90
  91 static void
  92 clutter_fixed_layout_get_preferred_height (ClutterLayoutManager *manager,
  93                                            ClutterContainer     *container,
  94                                            gfloat                for_width,
  95                                            gfloat               *min_height_p,
  96                                            gfloat               *nat_height_p)
  97 {
  98   ClutterActor *actor, *child;
  99   gdouble min_bottom;
 100   gdouble natural_bottom;
 101
 102   min_bottom = 0;
 103   natural_bottom = 0;
 104
 105   actor = CLUTTER_ACTOR (container);
 106
 107   for (child = clutter_actor_get_first_child (actor);
 108        child != NULL;
 109        child = clutter_actor_get_next_sibling (child))
 110     {
 111       gfloat child_y, child_min, child_natural;
 112
 113       child_y = clutter_actor_get_y (child);
 114
 115       clutter_actor_get_preferred_size (child,
 116                                         NULL, &child_min,
 117                                         NULL, &child_natural);
 118
 119       if (child_y + child_min > min_bottom)
 120         min_bottom = child_y + child_min;
 121
 122       if (child_y + child_natural > natural_bottom)
 123         natural_bottom = child_y + child_natural;
 124     }
 125
 126   if (min_height_p)
 127     *min_height_p = min_bottom;
 128
 129   if (nat_height_p)
 130     *nat_height_p = natural_bottom;
 131 }
 132
 133 static void
 134 clutter_fixed_layout_allocate (ClutterLayoutManager   *manager,
 135                                ClutterContainer       *container,
 136                                const ClutterActorBox  *allocation,
 137                                ClutterAllocationFlags  flags)
 138 {
 139   ClutterActor *child;
 140
 141   for (child = clutter_actor_get_first_child (CLUTTER_ACTOR (container));
 142        child != NULL;
 143        child = clutter_actor_get_next_sibling (child))
 144     {
 145       clutter_actor_allocate_preferred_size (child, flags);
 146     }
 147 }
 148
 149 static void
 150 clutter_fixed_layout_class_init (ClutterFixedLayoutClass *klass)
 151 {
 152   ClutterLayoutManagerClass *manager_class =
 153     CLUTTER_LAYOUT_MANAGER_CLASS (klass);
 154
 155   manager_class->get_preferred_width =
 156     clutter_fixed_layout_get_preferred_width;
 157   manager_class->get_preferred_height =
 158     clutter_fixed_layout_get_preferred_height;
 159   manager_class->allocate = clutter_fixed_layout_allocate;
 160 }
 161
 162 static void
 163 clutter_fixed_layout_init (ClutterFixedLayout *self)
 164 {
 165 }
 166
 167 /**
 168  * clutter_fixed_layout_new:
 169  *
 170  * Creates a new #ClutterFixedLayout
 171  *
 172  * Return value: the newly created #ClutterFixedLayout
 173  *
 174  * Since: 1.2
 175  */
 176 ClutterLayoutManager *
 177 clutter_fixed_layout_new (void)
 178 {
 179   return g_object_new (CLUTTER_TYPE_FIXED_LAYOUT, NULL);
 180 }