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_running_transformation (GtkThemingBackground *bg,
  44                                                       cairo_t              *cr)
  45 {
  46   gboolean running;
  47   gdouble progress;
  48   cairo_pattern_t *other_pattern;
  49   GtkStateFlags other_flags;
  50   GdkRGBA other_bg;
  51   cairo_pattern_t *new_pattern = NULL;
  52
  53   running = gtk_theming_engine_state_is_running (bg->engine, GTK_STATE_PRELIGHT, &progress);
  54
  55   if (!running)
  56     return;
  57
  58   if (bg->flags & GTK_STATE_FLAG_PRELIGHT)
  59     {
  60       other_flags = bg->flags & ~(GTK_STATE_FLAG_PRELIGHT);
  61       progress = 1 - progress;
  62     }
  63   else
  64     other_flags = bg->flags | GTK_STATE_FLAG_PRELIGHT;
  65
  66   gtk_theming_engine_get_background_color (bg->engine, other_flags, &other_bg);
  67   gtk_theming_engine_get (bg->engine, other_flags,
  68                           "background-image", &other_pattern,
  69                           NULL);
  70
  71   if (bg->pattern && other_pattern)
  72     {
  73       cairo_pattern_type_t type, other_type;
  74       gint n0, n1;
  75
  76       cairo_pattern_get_color_stop_count (bg->pattern, &n0);
  77       cairo_pattern_get_color_stop_count (other_pattern, &n1);
  78       type = cairo_pattern_get_type (bg->pattern);
  79       other_type = cairo_pattern_get_type (other_pattern);
  80
  81       if (type == other_type && n0 == n1)
  82         {
  83           gdouble offset0, red0, green0, blue0, alpha0;
  84           gdouble offset1, red1, green1, blue1, alpha1;
  85           gdouble x00, x01, y00, y01, x10, x11, y10, y11;
  86           gdouble r00, r01, r10, r11;
  87           guint i;
  88
  89           if (type == CAIRO_PATTERN_TYPE_LINEAR)
  90             {
  91               cairo_pattern_get_linear_points (bg->pattern, &x00, &y00, &x01, &y01);
  92               cairo_pattern_get_linear_points (other_pattern, &x10, &y10, &x11, &y11);
  93
  94               new_pattern = cairo_pattern_create_linear (x00 + (x10 - x00) * progress,
  95                                                          y00 + (y10 - y00) * progress,
  96                                                          x01 + (x11 - x01) * progress,
  97                                                          y01 + (y11 - y01) * progress);
  98             }
  99           else
 100             {
 101               cairo_pattern_get_radial_circles (bg->pattern, &x00, &y00, &r00, &x01, &y01, &r01);
 102               cairo_pattern_get_radial_circles (other_pattern, &x10, &y10, &r10, &x11, &y11, &r11);
 103
 104               new_pattern = cairo_pattern_create_radial (x00 + (x10 - x00) * progress,
 105                                                          y00 + (y10 - y00) * progress,
 106                                                          r00 + (r10 - r00) * progress,
 107                                                          x01 + (x11 - x01) * progress,
 108                                                          y01 + (y11 - y01) * progress,
 109                                                          r01 + (r11 - r01) * progress);
 110             }
 111
 112           cairo_pattern_set_filter (new_pattern, CAIRO_FILTER_FAST);
 113           i = 0;
 114
 115           /* Blend both gradients into one */
 116           while (i < n0 && i < n1)
 117             {
 118               cairo_pattern_get_color_stop_rgba (bg->pattern, i,
 119                                                  &offset0,
 120                                                  &red0, &green0, &blue0,
 121                                                  &alpha0);
 122               cairo_pattern_get_color_stop_rgba (other_pattern, i,
 123                                                  &offset1,
 124                                                  &red1, &green1, &blue1,
 125                                                  &alpha1);
 126
 127               cairo_pattern_add_color_stop_rgba (new_pattern,
 128                                                  offset0 + ((offset1 - offset0) * progress),
 129                                                  red0 + ((red1 - red0) * progress),
 130                                                  green0 + ((green1 - green0) * progress),
 131                                                  blue0 + ((blue1 - blue0) * progress),
 132                                                  alpha0 + ((alpha1 - alpha0) * progress));
 133               i++;
 134             }
 135         }
 136       else
 137         {
 138           cairo_save (cr);
 139
 140           cairo_rectangle (cr, 0, 0, bg->paint_area.width, bg->paint_area.height);
 141           cairo_clip (cr);
 142
 143           cairo_push_group (cr);
 144
 145           cairo_scale (cr, bg->paint_area.width, bg->paint_area.height);
 146           cairo_set_source (cr, other_pattern);
 147           cairo_paint_with_alpha (cr, progress);
 148           cairo_set_source (cr, bg->pattern);
 149           cairo_paint_with_alpha (cr, 1.0 - progress);
 150
 151           new_pattern = cairo_pop_group (cr);
 152
 153           cairo_restore (cr);
 154         }
 155     }
 156   else if (bg->pattern || other_pattern)
 157     {
 158       cairo_pattern_t *p;
 159       const GdkRGBA *c;
 160       gdouble x0, y0, x1, y1, r0, r1;
 161       gint n, i;
 162
 163       /* Blend a pattern with a color */
 164       if (bg->pattern)
 165         {
 166           p = bg->pattern;
 167           c = &other_bg;
 168           progress = 1 - progress;
 169         }
 170       else
 171         {
 172           p = other_pattern;
 173           c = &bg->bg_color;
 174         }
 175
 176       if (cairo_pattern_get_type (p) == CAIRO_PATTERN_TYPE_LINEAR)
 177         {
 178           cairo_pattern_get_linear_points (p, &x0, &y0, &x1, &y1);
 179           new_pattern = cairo_pattern_create_linear (x0, y0, x1, y1);
 180         }
 181       else
 182         {
 183           cairo_pattern_get_radial_circles (p, &x0, &y0, &r0, &x1, &y1, &r1);
 184           new_pattern = cairo_pattern_create_radial (x0, y0, r0, x1, y1, r1);
 185         }
 186
 187       cairo_pattern_get_color_stop_count (p, &n);
 188
 189       for (i = 0; i < n; i++)
 190         {
 191           gdouble red1, green1, blue1, alpha1;
 192           gdouble offset;
 193
 194           cairo_pattern_get_color_stop_rgba (p, i,
 195                                              &offset,
 196                                              &red1, &green1, &blue1,
 197                                              &alpha1);
 198           cairo_pattern_add_color_stop_rgba (new_pattern, offset,
 199                                              c->red + ((red1 - c->red) * progress),
 200                                              c->green + ((green1 - c->green) * progress),
 201                                              c->blue + ((blue1 - c->blue) * progress),
 202                                              c->alpha + ((alpha1 - c->alpha) * progress));
 203         }
 204     }
 205   else
 206     {
 207       /* Merge just colors */
 208       new_pattern = cairo_pattern_create_rgba (CLAMP (bg->bg_color.red + ((other_bg.red - bg->bg_color.red) * progress), 0, 1),
 209                                                CLAMP (bg->bg_color.green + ((other_bg.green - bg->bg_color.green) * progress), 0, 1),
 210                                                CLAMP (bg->bg_color.blue + ((other_bg.blue - bg->bg_color.blue) * progress), 0, 1),
 211                                                CLAMP (bg->bg_color.alpha + ((other_bg.alpha - bg->bg_color.alpha) * progress), 0, 1));
 212     }
 213
 214   if (new_pattern)
 215     {
 216       /* Replace pattern to use */
 217       cairo_pattern_destroy (bg->pattern);
 218       bg->pattern = new_pattern;
 219     }
 220
 221   if (other_pattern)
 222     cairo_pattern_destroy (other_pattern);
 223 }
 224
 225 static void
 226 _gtk_theming_background_apply_origin (GtkThemingBackground *bg)
 227 {
 228   GtkCssArea origin;
 229   cairo_rectangle_t image_rect;
 230
 231   gtk_theming_engine_get (bg->engine, bg->flags,
 232                           "background-origin", &origin,
 233                           NULL);
 234
 235   /* The default size of the background image depends on the
 236      background-origin value as this affects the top left
 237      and the bottom right corners. */
 238   switch (origin) {
 239   case GTK_CSS_AREA_BORDER_BOX:
 240     image_rect.x = 0;
 241     image_rect.y = 0;
 242     image_rect.width = bg->paint_area.width;
 243     image_rect.height = bg->paint_area.height;
 244     break;
 245   case GTK_CSS_AREA_CONTENT_BOX:
 246     image_rect.x = bg->border.left + bg->padding.left;
 247     image_rect.y = bg->border.top + bg->padding.top;
 248     image_rect.width = bg->paint_area.width - bg->border.left - bg->border.right - bg->padding.left - bg->padding.right;
 249     image_rect.height = bg->paint_area.height - bg->border.top - bg->border.bottom - bg->padding.top - bg->padding.bottom;
 250     break;
 251   case GTK_CSS_AREA_PADDING_BOX:
 252   default:
 253     image_rect.x = bg->border.left;
 254     image_rect.y = bg->border.top;
 255     image_rect.width = bg->paint_area.width - bg->border.left - bg->border.right;
 256     image_rect.height = bg->paint_area.height - bg->border.top - bg->border.bottom;
 257     break;
 258   }
 259
 260   bg->image_rect = image_rect;
 261 }
 262
 263 static void
 264 _gtk_theming_background_apply_clip (GtkThemingBackground *bg)
 265 {
 266   GtkCssArea clip;
 267
 268   gtk_theming_engine_get (bg->engine, bg->flags,
 269                           "background-clip", &clip,
 270                           NULL);
 271
 272   if (clip == GTK_CSS_AREA_PADDING_BOX)
 273     {
 274       _gtk_rounded_box_shrink (&bg->clip_box,
 275                                bg->border.top, bg->border.right,
 276                                bg->border.bottom, bg->border.left);
 277     }
 278   else if (clip == GTK_CSS_AREA_CONTENT_BOX)
 279     {
 280       _gtk_rounded_box_shrink (&bg->clip_box,
 281                                bg->border.top + bg->padding.top,
 282                                bg->border.right + bg->padding.right,
 283                                bg->border.bottom + bg->padding.bottom,
 284                                bg->border.left + bg->padding.left);
 285     }
 286 }
 287
 288 static void
 289 _gtk_theming_background_paint (GtkThemingBackground *bg,
 290                                cairo_t              *cr)
 291 {
 292   _gtk_rounded_box_path (&bg->clip_box, cr);
 293   gdk_cairo_set_source_rgba (cr, &bg->bg_color);
 294
 295   if (bg->pattern)
 296     {
 297       GtkCssBackgroundRepeat *repeat;
 298       cairo_surface_t *surface;
 299       int scale_width, scale_height;
 300
 301       gtk_theming_engine_get (bg->engine, bg->flags,
 302                               "background-repeat", &repeat,
 303                               NULL);
 304
 305       if (cairo_pattern_get_surface (bg->pattern, &surface) != CAIRO_STATUS_SUCCESS)
 306         surface = NULL;
 307
 308       if (surface && repeat)
 309         {
 310           scale_width = cairo_image_surface_get_width (surface);
 311           scale_height = cairo_image_surface_get_height (surface);
 312           if (repeat->repeat == GTK_CSS_BACKGROUND_REPEAT_STYLE_REPEAT)
 313             cairo_pattern_set_extend (bg->pattern, CAIRO_EXTEND_REPEAT);
 314           else if (repeat->repeat == GTK_CSS_BACKGROUND_REPEAT_STYLE_NO_REPEAT)
 315             cairo_pattern_set_extend (bg->pattern, CAIRO_EXTEND_NONE);
 316         }
 317       else
 318         {
 319           cairo_pattern_set_extend (bg->pattern, CAIRO_EXTEND_PAD);
 320           scale_width = bg->image_rect.width;
 321           scale_height = bg->image_rect.height;
 322         }
 323
 324       if (scale_width && scale_height)
 325         {
 326           /* Fill background color first */
 327           cairo_fill_preserve (cr);
 328
 329           cairo_translate (cr, bg->image_rect.x, bg->image_rect.y);
 330           cairo_scale (cr, scale_width, scale_height);
 331           cairo_set_source (cr, bg->pattern);
 332           cairo_scale (cr, 1.0 / scale_width, 1.0 / scale_height);
 333           cairo_translate (cr, -bg->image_rect.x, -bg->image_rect.y);
 334
 335           g_free (repeat);
 336
 337           cairo_pattern_destroy (bg->pattern);
 338           bg->pattern = NULL;
 339         }
 340     }
 341
 342   cairo_fill (cr);
 343 }
 344
 345 static void
 346 _gtk_theming_background_apply_shadow (GtkThemingBackground *bg,
 347                                       cairo_t              *cr)
 348 {
 349   GtkShadow *box_shadow;
 350
 351   gtk_theming_engine_get (bg->engine, bg->flags,
 352                           "box-shadow", &box_shadow,
 353                           NULL);
 354
 355   if (box_shadow != NULL)
 356     {
 357       _gtk_box_shadow_render (box_shadow, cr, &bg->padding_box);
 358       _gtk_shadow_unref (box_shadow);
 359     }
 360 }
 361
 362 static void
 363 _gtk_theming_background_init_engine (GtkThemingBackground *bg)
 364 {
 365   bg->flags = gtk_theming_engine_get_state (bg->engine);
 366
 367   gtk_theming_engine_get_border (bg->engine, bg->flags, &bg->border);
 368   gtk_theming_engine_get_padding (bg->engine, bg->flags, &bg->padding);
 369   gtk_theming_engine_get_background_color (bg->engine, bg->flags, &bg->bg_color);
 370
 371   /* In the CSS box model, by default the background positioning area is
 372    * the padding-box, i.e. all the border-box minus the borders themselves,
 373    * which determines also its default size, see
 374    * http://dev.w3.org/csswg/css3-background/#background-origin
 375    *
 376    * In the future we might want to support different origins or clips, but
 377    * right now we just shrink to the default.
 378    */
 379   _gtk_rounded_box_init_rect (&bg->padding_box, 0, 0, bg->paint_area.width, bg->paint_area.height);
 380   _gtk_rounded_box_apply_border_radius (&bg->padding_box, bg->engine, bg->flags, bg->junction);
 381
 382   bg->clip_box = bg->padding_box;
 383   _gtk_rounded_box_shrink (&bg->padding_box,
 384                            bg->border.top, bg->border.right,
 385                            bg->border.bottom, bg->border.left);
 386
 387   _gtk_theming_background_apply_clip (bg);
 388   _gtk_theming_background_apply_origin (bg);
 389
 390   gtk_theming_engine_get (bg->engine, bg->flags,
 391                           "background-image", &bg->pattern,
 392                           NULL);
 393 }
 394
 395 void
 396 _gtk_theming_background_init (GtkThemingBackground *bg,
 397                               GtkThemingEngine     *engine,
 398                               gdouble               x,
 399                               gdouble               y,
 400                               gdouble               width,
 401                               gdouble               height,
 402                               GtkJunctionSides      junction)
 403 {
 404   g_assert (bg != NULL);
 405
 406   bg->engine = engine;
 407
 408   bg->paint_area.x = x;
 409   bg->paint_area.y = y;
 410   bg->paint_area.width = width;
 411   bg->paint_area.height = height;
 412
 413   bg->pattern = NULL;
 414   bg->junction = junction;
 415
 416   _gtk_theming_background_init_engine (bg);
 417 }
 418
 419 void
 420 _gtk_theming_background_render (GtkThemingBackground *bg,
 421                                 cairo_t              *cr)
 422 {
 423   cairo_save (cr);
 424   cairo_translate (cr, bg->paint_area.x, bg->paint_area.y);
 425
 426   _gtk_theming_background_apply_window_background (bg, cr);
 427   _gtk_theming_background_apply_running_transformation (bg, cr);
 428   _gtk_theming_background_paint (bg, cr);
 429   _gtk_theming_background_apply_shadow (bg, cr);
 430
 431   cairo_restore (cr);
 432 }
 433
 434 gboolean
 435 _gtk_theming_background_has_background_image (GtkThemingBackground *bg)
 436 {
 437   return (bg->pattern != NULL) ? TRUE : FALSE;
 438 }