Pileus Git - ~andy/gtk/blob - gtk/gtkthemingbackground.c

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 2010 Carlos Garnacho <carlosg@gnome.org>
   3  * Copyright (C) 2011 Red Hat, Inc.
   4  *
   5  * Authors: Carlos Garnacho <carlosg@gnome.org>
   6  *          Cosimo Cecchi <cosimoc@gnome.org>
   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, write to the
  20  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  21  * Boston, MA 02111-1307, USA.
  22  */
  23
  24 #include "gtkcsstypesprivate.h"
  25 #include "gtkthemingbackgroundprivate.h"
  26 #include "gtkthemingengineprivate.h"
  27
  28 #include <gdk/gdk.h>
  29
  30 static void
  31 _gtk_theming_background_apply_window_background (GtkThemingBackground *bg,
  32                                                  cairo_t              *cr)
  33 {
  34   if (gtk_theming_engine_has_class (bg->engine, "background"))
  35     {
  36       cairo_set_source_rgba (cr, 1.0, 1.0, 1.0, 0.0); /* transparent */
  37       cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
  38       cairo_paint (cr);
  39     }
  40 }
  41
  42 static void
  43 _gtk_theming_background_apply_origin (GtkThemingBackground *bg)
  44 {
  45   GtkCssArea origin;
  46   cairo_rectangle_t image_rect;
  47
  48   gtk_theming_engine_get (bg->engine, bg->flags,
  49                           "background-origin", &origin,
  50                           NULL);
  51
  52   /* The default size of the background image depends on the
  53      background-origin value as this affects the top left
  54      and the bottom right corners. */
  55   switch (origin) {
  56   case GTK_CSS_AREA_BORDER_BOX:
  57     image_rect.x = 0;
  58     image_rect.y = 0;
  59     image_rect.width = bg->paint_area.width;
  60     image_rect.height = bg->paint_area.height;
  61     break;
  62   case GTK_CSS_AREA_CONTENT_BOX:
  63     image_rect.x = bg->border.left + bg->padding.left;
  64     image_rect.y = bg->border.top + bg->padding.top;
  65     image_rect.width = bg->paint_area.width - bg->border.left - bg->border.right - bg->padding.left - bg->padding.right;
  66     image_rect.height = bg->paint_area.height - bg->border.top - bg->border.bottom - bg->padding.top - bg->padding.bottom;
  67     break;
  68   case GTK_CSS_AREA_PADDING_BOX:
  69   default:
  70     image_rect.x = bg->border.left;
  71     image_rect.y = bg->border.top;
  72     image_rect.width = bg->paint_area.width - bg->border.left - bg->border.right;
  73     image_rect.height = bg->paint_area.height - bg->border.top - bg->border.bottom;
  74     break;
  75   }
  76
  77   bg->image_rect = image_rect;
  78 }
  79
  80 static void
  81 _gtk_theming_background_apply_clip (GtkThemingBackground *bg)
  82 {
  83   GtkCssArea clip;
  84
  85   gtk_theming_engine_get (bg->engine, bg->flags,
  86                           "background-clip", &clip,
  87                           NULL);
  88
  89   if (clip == GTK_CSS_AREA_PADDING_BOX)
  90     {
  91       _gtk_rounded_box_shrink (&bg->clip_box,
  92                                bg->border.top, bg->border.right,
  93                                bg->border.bottom, bg->border.left);
  94     }
  95   else if (clip == GTK_CSS_AREA_CONTENT_BOX)
  96     {
  97       _gtk_rounded_box_shrink (&bg->clip_box,
  98                                bg->border.top + bg->padding.top,
  99                                bg->border.right + bg->padding.right,
 100                                bg->border.bottom + bg->padding.bottom,
 101                                bg->border.left + bg->padding.left);
 102     }
 103 }
 104
 105 static void
 106 _gtk_theming_background_paint (GtkThemingBackground *bg,
 107                                cairo_t              *cr)
 108 {
 109   cairo_save (cr);
 110
 111   _gtk_rounded_box_path (&bg->clip_box, cr);
 112   cairo_clip (cr);
 113
 114   gdk_cairo_set_source_rgba (cr, &bg->bg_color);
 115   cairo_paint (cr);
 116
 117   if (bg->image)
 118     {
 119       GtkCssBackgroundRepeat *repeat;
 120       double image_width, image_height;
 121
 122       gtk_theming_engine_get (bg->engine, bg->flags,
 123                               "background-repeat", &repeat,
 124                               NULL);
 125
 126       _gtk_css_image_get_concrete_size (bg->image,
 127                                         0, 0, /* XXX: needs background-size support */
 128                                         bg->image_rect.width, bg->image_rect.height,
 129                                         &image_width, &image_height);
 130
 131       cairo_translate (cr, bg->image_rect.x, bg->image_rect.y);
 132       /* XXX: repeat flags */
 133       _gtk_css_image_draw (bg->image, cr, image_width, image_height);
 134     }
 135
 136   cairo_restore (cr);
 137 }
 138
 139 static void
 140 _gtk_theming_background_apply_shadow (GtkThemingBackground *bg,
 141                                       cairo_t              *cr)
 142 {
 143   GtkShadow *box_shadow;
 144
 145   gtk_theming_engine_get (bg->engine, bg->flags,
 146                           "box-shadow", &box_shadow,
 147                           NULL);
 148
 149   if (box_shadow != NULL)
 150     {
 151       _gtk_box_shadow_render (box_shadow, cr, &bg->padding_box);
 152       _gtk_shadow_unref (box_shadow);
 153     }
 154 }
 155
 156 static void
 157 _gtk_theming_background_init_engine (GtkThemingBackground *bg)
 158 {
 159   bg->flags = gtk_theming_engine_get_state (bg->engine);
 160
 161   gtk_theming_engine_get_border (bg->engine, bg->flags, &bg->border);
 162   gtk_theming_engine_get_padding (bg->engine, bg->flags, &bg->padding);
 163   gtk_theming_engine_get_background_color (bg->engine, bg->flags, &bg->bg_color);
 164
 165   /* In the CSS box model, by default the background positioning area is
 166    * the padding-box, i.e. all the border-box minus the borders themselves,
 167    * which determines also its default size, see
 168    * http://dev.w3.org/csswg/css3-background/#background-origin
 169    *
 170    * In the future we might want to support different origins or clips, but
 171    * right now we just shrink to the default.
 172    */
 173   _gtk_rounded_box_init_rect (&bg->padding_box, 0, 0, bg->paint_area.width, bg->paint_area.height);
 174   _gtk_rounded_box_apply_border_radius (&bg->padding_box, bg->engine, bg->flags, bg->junction);
 175
 176   bg->clip_box = bg->padding_box;
 177   _gtk_rounded_box_shrink (&bg->padding_box,
 178                            bg->border.top, bg->border.right,
 179                            bg->border.bottom, bg->border.left);
 180
 181   _gtk_theming_background_apply_clip (bg);
 182   _gtk_theming_background_apply_origin (bg);
 183
 184   bg->image = g_value_get_object (_gtk_theming_engine_peek_property (bg->engine, "background-image"));
 185 }
 186
 187 void
 188 _gtk_theming_background_init (GtkThemingBackground *bg,
 189                               GtkThemingEngine     *engine,
 190                               gdouble               x,
 191                               gdouble               y,
 192                               gdouble               width,
 193                               gdouble               height,
 194                               GtkJunctionSides      junction)
 195 {
 196   g_assert (bg != NULL);
 197
 198   bg->engine = engine;
 199
 200   bg->paint_area.x = x;
 201   bg->paint_area.y = y;
 202   bg->paint_area.width = width;
 203   bg->paint_area.height = height;
 204
 205   bg->image = NULL;
 206   bg->junction = junction;
 207
 208   _gtk_theming_background_init_engine (bg);
 209 }
 210
 211 void
 212 _gtk_theming_background_render (GtkThemingBackground *bg,
 213                                 cairo_t              *cr)
 214 {
 215   cairo_save (cr);
 216   cairo_translate (cr, bg->paint_area.x, bg->paint_area.y);
 217
 218   _gtk_theming_background_apply_window_background (bg, cr);
 219   _gtk_theming_background_paint (bg, cr);
 220   _gtk_theming_background_apply_shadow (bg, cr);
 221
 222   cairo_restore (cr);
 223 }
 224
 225 gboolean
 226 _gtk_theming_background_has_background_image (GtkThemingBackground *bg)
 227 {
 228   return (bg->image != NULL) ? TRUE : FALSE;
 229 }