Pileus Git - ~andy/gtk/blob - tests/gtkoffscreenbox.c

   1 /*
   2  * gtkoffscreenbox.c
   3  */
   4
   5 #include "config.h"
   6
   7 #include <math.h>
   8 #include <gtk/gtk.h>
   9
  10 #include "gtkoffscreenbox.h"
  11
  12 static void        gtk_offscreen_box_realize       (GtkWidget       *widget);
  13 static void        gtk_offscreen_box_unrealize     (GtkWidget       *widget);
  14 static void        gtk_offscreen_box_get_preferred_width  (GtkWidget *widget,
  15                                                            gint      *minimum,
  16                                                            gint      *natural);
  17 static void        gtk_offscreen_box_get_preferred_height (GtkWidget *widget,
  18                                                            gint      *minimum,
  19                                                            gint      *natural);
  20 static void        gtk_offscreen_box_size_allocate (GtkWidget       *widget,
  21                                                     GtkAllocation   *allocation);
  22 static gboolean    gtk_offscreen_box_damage        (GtkWidget       *widget,
  23                                                     GdkEventExpose  *event);
  24 static gboolean    gtk_offscreen_box_draw          (GtkWidget       *widget,
  25                                                     cairo_t         *cr);
  26
  27 static void        gtk_offscreen_box_add           (GtkContainer    *container,
  28                                                     GtkWidget       *child);
  29 static void        gtk_offscreen_box_remove        (GtkContainer    *container,
  30                                                     GtkWidget       *widget);
  31 static void        gtk_offscreen_box_forall        (GtkContainer    *container,
  32                                                     gboolean         include_internals,
  33                                                     GtkCallback      callback,
  34                                                     gpointer         callback_data);
  35 static GType       gtk_offscreen_box_child_type    (GtkContainer    *container);
  36
  37 #define CHILD1_SIZE_SCALE 1.0
  38 #define CHILD2_SIZE_SCALE 1.0
  39
  40 G_DEFINE_TYPE (GtkOffscreenBox, gtk_offscreen_box, GTK_TYPE_CONTAINER);
  41
  42 static void
  43 to_child_2 (GtkOffscreenBox *offscreen_box,
  44             double widget_x, double widget_y,
  45             double *x_out, double *y_out)
  46 {
  47   GtkAllocation child_area;
  48   double x, y, xr, yr;
  49   double cos_angle, sin_angle;
  50
  51   x = widget_x;
  52   y = widget_y;
  53
  54   if (offscreen_box->child1 && gtk_widget_get_visible (offscreen_box->child1))
  55     {
  56       gtk_widget_get_allocation (offscreen_box->child1, &child_area);
  57       y -= child_area.height;
  58     }
  59
  60   gtk_widget_get_allocation (offscreen_box->child2, &child_area);
  61
  62   x -= child_area.width / 2;
  63   y -= child_area.height / 2;
  64
  65   cos_angle = cos (-offscreen_box->angle);
  66   sin_angle = sin (-offscreen_box->angle);
  67
  68   xr = x * cos_angle - y * sin_angle;
  69   yr = x * sin_angle + y * cos_angle;
  70   x = xr;
  71   y = yr;
  72
  73   x += child_area.width / 2;
  74   y += child_area.height / 2;
  75
  76   *x_out = x;
  77   *y_out = y;
  78 }
  79
  80 static void
  81 to_parent_2 (GtkOffscreenBox *offscreen_box,
  82              double offscreen_x, double offscreen_y,
  83              double *x_out, double *y_out)
  84 {
  85   GtkAllocation child_area;
  86   double x, y, xr, yr;
  87   double cos_angle, sin_angle;
  88
  89   gtk_widget_get_allocation (offscreen_box->child2, &child_area);
  90
  91   x = offscreen_x;
  92   y = offscreen_y;
  93
  94   x -= child_area.width / 2;
  95   y -= child_area.height / 2;
  96
  97   cos_angle = cos (offscreen_box->angle);
  98   sin_angle = sin (offscreen_box->angle);
  99
 100   xr = x * cos_angle - y * sin_angle;
 101   yr = x * sin_angle + y * cos_angle;
 102   x = xr;
 103   y = yr;
 104
 105   x += child_area.width / 2;
 106   y += child_area.height / 2;
 107
 108   if (offscreen_box->child1 && gtk_widget_get_visible (offscreen_box->child1))
 109     {
 110       gtk_widget_get_allocation (offscreen_box->child1, &child_area);
 111       y += child_area.height;
 112     }
 113
 114   *x_out = x;
 115   *y_out = y;
 116 }
 117
 118 static void
 119 gtk_offscreen_box_class_init (GtkOffscreenBoxClass *klass)
 120 {
 121   GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
 122   GtkContainerClass *container_class = GTK_CONTAINER_CLASS (klass);
 123
 124   widget_class->realize = gtk_offscreen_box_realize;
 125   widget_class->unrealize = gtk_offscreen_box_unrealize;
 126   widget_class->get_preferred_width = gtk_offscreen_box_get_preferred_width;
 127   widget_class->get_preferred_height = gtk_offscreen_box_get_preferred_height;
 128   widget_class->size_allocate = gtk_offscreen_box_size_allocate;
 129   widget_class->draw = gtk_offscreen_box_draw;
 130
 131   g_signal_override_class_closure (g_signal_lookup ("damage-event", GTK_TYPE_WIDGET),
 132                                    GTK_TYPE_OFFSCREEN_BOX,
 133                                    g_cclosure_new (G_CALLBACK (gtk_offscreen_box_damage),
 134                                                    NULL, NULL));
 135
 136   container_class->add = gtk_offscreen_box_add;
 137   container_class->remove = gtk_offscreen_box_remove;
 138   container_class->forall = gtk_offscreen_box_forall;
 139   container_class->child_type = gtk_offscreen_box_child_type;
 140 }
 141
 142 static void
 143 gtk_offscreen_box_init (GtkOffscreenBox *offscreen_box)
 144 {
 145   gtk_widget_set_has_window (GTK_WIDGET (offscreen_box), TRUE);
 146 }
 147
 148 GtkWidget *
 149 gtk_offscreen_box_new (void)
 150 {
 151   return g_object_new (GTK_TYPE_OFFSCREEN_BOX, NULL);
 152 }
 153
 154 static GdkWindow *
 155 pick_offscreen_child (GdkWindow *offscreen_window,
 156                       double widget_x, double widget_y,
 157                       GtkOffscreenBox *offscreen_box)
 158 {
 159  GtkAllocation child_area;
 160  double x, y;
 161
 162  /* First check for child 2 */
 163  if (offscreen_box->child2 &&
 164      gtk_widget_get_visible (offscreen_box->child2))
 165     {
 166       to_child_2 (offscreen_box,
 167                   widget_x, widget_y,
 168                   &x, &y);
 169
 170       gtk_widget_get_allocation (offscreen_box->child2, &child_area);
 171
 172       if (x >= 0 && x < child_area.width &&
 173           y >= 0 && y < child_area.height)
 174         return offscreen_box->offscreen_window2;
 175     }
 176
 177  if (offscreen_box->child1 && gtk_widget_get_visible (offscreen_box->child1))
 178    {
 179      x = widget_x;
 180      y = widget_y;
 181
 182      gtk_widget_get_allocation (offscreen_box->child1, &child_area);
 183
 184      if (x >= 0 && x < child_area.width &&
 185          y >= 0 && y < child_area.height)
 186        return offscreen_box->offscreen_window1;
 187    }
 188
 189   return NULL;
 190 }
 191
 192 static void
 193 offscreen_window_to_parent1 (GdkWindow       *offscreen_window,
 194                              double           offscreen_x,
 195                              double           offscreen_y,
 196                              double          *parent_x,
 197                              double          *parent_y,
 198                              GtkOffscreenBox *offscreen_box)
 199 {
 200   *parent_x = offscreen_x;
 201   *parent_y = offscreen_y;
 202 }
 203
 204 static void
 205 offscreen_window_from_parent1 (GdkWindow       *window,
 206                                double           parent_x,
 207                                double           parent_y,
 208                                double          *offscreen_x,
 209                                double          *offscreen_y,
 210                                GtkOffscreenBox *offscreen_box)
 211 {
 212   *offscreen_x = parent_x;
 213   *offscreen_y = parent_y;
 214 }
 215
 216 static void
 217 offscreen_window_to_parent2 (GdkWindow       *offscreen_window,
 218                              double           offscreen_x,
 219                              double           offscreen_y,
 220                              double          *parent_x,
 221                              double          *parent_y,
 222                              GtkOffscreenBox *offscreen_box)
 223 {
 224   to_parent_2 (offscreen_box,
 225               offscreen_x, offscreen_y,
 226               parent_x, parent_y);
 227 }
 228
 229 static void
 230 offscreen_window_from_parent2 (GdkWindow       *window,
 231                                double           parent_x,
 232                                double           parent_y,
 233                                double          *offscreen_x,
 234                                double          *offscreen_y,
 235                                GtkOffscreenBox *offscreen_box)
 236 {
 237   to_child_2 (offscreen_box,
 238               parent_x, parent_y,
 239               offscreen_x, offscreen_y);
 240 }
 241
 242 static cairo_surface_t *
 243 gdk_offscreen_box_create_alpha_image_surface (GdkWindow *offscreen,
 244                                               gint       width,
 245                                               gint       height)
 246 {
 247   return cairo_image_surface_create (CAIRO_FORMAT_ARGB32, width, height);
 248 }
 249
 250 static void
 251 gtk_offscreen_box_realize (GtkWidget *widget)
 252 {
 253   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (widget);
 254   GtkAllocation allocation, child_area;
 255   GtkStyleContext *context;
 256   GdkWindow *window;
 257   GdkWindowAttr attributes;
 258   gint attributes_mask;
 259   guint border_width;
 260   GtkRequisition child_requisition;
 261   int start_y = 0;
 262
 263   gtk_widget_set_realized (widget, TRUE);
 264
 265   border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
 266
 267   gtk_widget_get_allocation (widget, &allocation);
 268
 269   attributes.x = allocation.x + border_width;
 270   attributes.y = allocation.y + border_width;
 271   attributes.width = allocation.width - 2 * border_width;
 272   attributes.height = allocation.height - 2 * border_width;
 273   attributes.window_type = GDK_WINDOW_CHILD;
 274   attributes.event_mask = gtk_widget_get_events (widget)
 275                         | GDK_EXPOSURE_MASK
 276                         | GDK_POINTER_MOTION_MASK
 277                         | GDK_BUTTON_PRESS_MASK
 278                         | GDK_BUTTON_RELEASE_MASK
 279                         | GDK_SCROLL_MASK
 280                         | GDK_ENTER_NOTIFY_MASK
 281                         | GDK_LEAVE_NOTIFY_MASK;
 282
 283   attributes.visual = gtk_widget_get_visual (widget);
 284   attributes.wclass = GDK_INPUT_OUTPUT;
 285
 286   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
 287
 288   window = gdk_window_new (gtk_widget_get_parent_window (widget),
 289                            &attributes, attributes_mask);
 290   gtk_widget_set_window (widget, window);
 291   gdk_window_set_user_data (window, widget);
 292
 293   g_signal_connect (window, "pick-embedded-child",
 294                     G_CALLBACK (pick_offscreen_child), offscreen_box);
 295
 296   attributes.window_type = GDK_WINDOW_OFFSCREEN;
 297
 298   /* Child 1 */
 299   attributes.x = attributes.y = 0;
 300   if (offscreen_box->child1 && gtk_widget_get_visible (offscreen_box->child1))
 301     {
 302       gtk_widget_get_allocation (offscreen_box->child1, &child_area);
 303
 304       attributes.width = child_area.width;
 305       attributes.height = child_area.height;
 306       start_y += child_area.height;
 307     }
 308   offscreen_box->offscreen_window1 = gdk_window_new (gtk_widget_get_root_window (widget),
 309                                                      &attributes, attributes_mask);
 310   gdk_window_set_user_data (offscreen_box->offscreen_window1, widget);
 311   if (offscreen_box->child1)
 312     gtk_widget_set_parent_window (offscreen_box->child1, offscreen_box->offscreen_window1);
 313
 314   gdk_offscreen_window_set_embedder (offscreen_box->offscreen_window1,
 315                                      window);
 316
 317   g_signal_connect (offscreen_box->offscreen_window1, "to-embedder",
 318                     G_CALLBACK (offscreen_window_to_parent1), offscreen_box);
 319   g_signal_connect (offscreen_box->offscreen_window1, "from-embedder",
 320                     G_CALLBACK (offscreen_window_from_parent1), offscreen_box);
 321
 322   /* Child 2 */
 323   attributes.y = start_y;
 324   child_requisition.width = child_requisition.height = 0;
 325   if (offscreen_box->child2 && gtk_widget_get_visible (offscreen_box->child2))
 326     {
 327       gtk_widget_get_allocation (offscreen_box->child2, &child_area);
 328
 329       attributes.width = child_area.width;
 330       attributes.height = child_area.height;
 331     }
 332   offscreen_box->offscreen_window2 = gdk_window_new (gtk_widget_get_root_window (widget),
 333                                                      &attributes, attributes_mask);
 334   gdk_window_set_user_data (offscreen_box->offscreen_window2, widget);
 335   if (offscreen_box->child2)
 336     gtk_widget_set_parent_window (offscreen_box->child2, offscreen_box->offscreen_window2);
 337   gdk_offscreen_window_set_embedder (offscreen_box->offscreen_window2,
 338                                      window);
 339
 340   g_signal_connect (offscreen_box->offscreen_window2, "create-surface",
 341                     G_CALLBACK (gdk_offscreen_box_create_alpha_image_surface),
 342                     offscreen_box);
 343   g_signal_connect (offscreen_box->offscreen_window2, "to-embedder",
 344                     G_CALLBACK (offscreen_window_to_parent2), offscreen_box);
 345   g_signal_connect (offscreen_box->offscreen_window2, "from-embedder",
 346                     G_CALLBACK (offscreen_window_from_parent2), offscreen_box);
 347
 348   context = gtk_widget_get_style_context (widget);
 349   gtk_style_context_set_background (context, window);
 350   gtk_style_context_set_background (context, offscreen_box->offscreen_window1);
 351   gtk_style_context_set_background (context, offscreen_box->offscreen_window2);
 352
 353   gdk_window_show (offscreen_box->offscreen_window1);
 354   gdk_window_show (offscreen_box->offscreen_window2);
 355 }
 356
 357 static void
 358 gtk_offscreen_box_unrealize (GtkWidget *widget)
 359 {
 360   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (widget);
 361
 362   gdk_window_set_user_data (offscreen_box->offscreen_window1, NULL);
 363   gdk_window_destroy (offscreen_box->offscreen_window1);
 364   offscreen_box->offscreen_window1 = NULL;
 365
 366   gdk_window_set_user_data (offscreen_box->offscreen_window2, NULL);
 367   gdk_window_destroy (offscreen_box->offscreen_window2);
 368   offscreen_box->offscreen_window2 = NULL;
 369
 370   GTK_WIDGET_CLASS (gtk_offscreen_box_parent_class)->unrealize (widget);
 371 }
 372
 373 static GType
 374 gtk_offscreen_box_child_type (GtkContainer *container)
 375 {
 376   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (container);
 377
 378   if (offscreen_box->child1 && offscreen_box->child2)
 379     return G_TYPE_NONE;
 380
 381   return GTK_TYPE_WIDGET;
 382 }
 383
 384 static void
 385 gtk_offscreen_box_add (GtkContainer *container,
 386                        GtkWidget    *widget)
 387 {
 388   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (container);
 389
 390   if (!offscreen_box->child1)
 391     gtk_offscreen_box_add1 (offscreen_box, widget);
 392   else if (!offscreen_box->child2)
 393     gtk_offscreen_box_add2 (offscreen_box, widget);
 394   else
 395     g_warning ("GtkOffscreenBox cannot have more than 2 children\n");
 396 }
 397
 398 void
 399 gtk_offscreen_box_add1 (GtkOffscreenBox *offscreen_box,
 400                         GtkWidget       *child)
 401 {
 402   g_return_if_fail (GTK_IS_OFFSCREEN_BOX (offscreen_box));
 403   g_return_if_fail (GTK_IS_WIDGET (child));
 404
 405   if (offscreen_box->child1 == NULL)
 406     {
 407       gtk_widget_set_parent_window (child, offscreen_box->offscreen_window1);
 408       gtk_widget_set_parent (child, GTK_WIDGET (offscreen_box));
 409       offscreen_box->child1 = child;
 410     }
 411 }
 412
 413 void
 414 gtk_offscreen_box_add2 (GtkOffscreenBox  *offscreen_box,
 415                         GtkWidget    *child)
 416 {
 417   g_return_if_fail (GTK_IS_OFFSCREEN_BOX (offscreen_box));
 418   g_return_if_fail (GTK_IS_WIDGET (child));
 419
 420   if (offscreen_box->child2 == NULL)
 421     {
 422       gtk_widget_set_parent_window (child, offscreen_box->offscreen_window2);
 423       gtk_widget_set_parent (child, GTK_WIDGET (offscreen_box));
 424       offscreen_box->child2 = child;
 425     }
 426 }
 427
 428 static void
 429 gtk_offscreen_box_remove (GtkContainer *container,
 430                           GtkWidget    *widget)
 431 {
 432   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (container);
 433   gboolean was_visible;
 434
 435   was_visible = gtk_widget_get_visible (widget);
 436
 437   if (offscreen_box->child1 == widget)
 438     {
 439       gtk_widget_unparent (widget);
 440
 441       offscreen_box->child1 = NULL;
 442
 443       if (was_visible && gtk_widget_get_visible (GTK_WIDGET (container)))
 444         gtk_widget_queue_resize (GTK_WIDGET (container));
 445     }
 446   else if (offscreen_box->child2 == widget)
 447     {
 448       gtk_widget_unparent (widget);
 449
 450       offscreen_box->child2 = NULL;
 451
 452       if (was_visible && gtk_widget_get_visible (GTK_WIDGET (container)))
 453         gtk_widget_queue_resize (GTK_WIDGET (container));
 454     }
 455 }
 456
 457 static void
 458 gtk_offscreen_box_forall (GtkContainer *container,
 459                           gboolean      include_internals,
 460                           GtkCallback   callback,
 461                           gpointer      callback_data)
 462 {
 463   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (container);
 464
 465   g_return_if_fail (callback != NULL);
 466
 467   if (offscreen_box->child1)
 468     (*callback) (offscreen_box->child1, callback_data);
 469   if (offscreen_box->child2)
 470     (*callback) (offscreen_box->child2, callback_data);
 471 }
 472
 473 void
 474 gtk_offscreen_box_set_angle (GtkOffscreenBox  *offscreen_box,
 475                              gdouble           angle)
 476 {
 477   g_return_if_fail (GTK_IS_OFFSCREEN_BOX (offscreen_box));
 478
 479   offscreen_box->angle = angle;
 480   gtk_widget_queue_draw (GTK_WIDGET (offscreen_box));
 481
 482   /* TODO: Really needs to resent pointer events if over the rotated window */
 483 }
 484
 485
 486 static void
 487 gtk_offscreen_box_size_request (GtkWidget      *widget,
 488                                 GtkRequisition *requisition)
 489 {
 490   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (widget);
 491   int w, h;
 492   guint border_width;
 493
 494   w = 0;
 495   h = 0;
 496
 497   if (offscreen_box->child1 && gtk_widget_get_visible (offscreen_box->child1))
 498     {
 499       GtkRequisition child_requisition;
 500
 501       gtk_widget_get_preferred_size ( (offscreen_box->child1),
 502                                  &child_requisition, NULL);
 503
 504       w = MAX (w, CHILD1_SIZE_SCALE * child_requisition.width);
 505       h += CHILD1_SIZE_SCALE * child_requisition.height;
 506     }
 507
 508   if (offscreen_box->child2 && gtk_widget_get_visible (offscreen_box->child2))
 509     {
 510       GtkRequisition child_requisition;
 511
 512       gtk_widget_get_preferred_size ( (offscreen_box->child2),
 513                                  &child_requisition, NULL);
 514
 515       w = MAX (w, CHILD2_SIZE_SCALE * child_requisition.width);
 516       h += CHILD2_SIZE_SCALE * child_requisition.height;
 517     }
 518
 519   border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
 520   requisition->width = border_width * 2 + w;
 521   requisition->height = border_width * 2 + h;
 522 }
 523
 524 static void
 525 gtk_offscreen_box_get_preferred_width (GtkWidget *widget,
 526                                        gint      *minimum,
 527                                        gint      *natural)
 528 {
 529   GtkRequisition requisition;
 530
 531   gtk_offscreen_box_size_request (widget, &requisition);
 532
 533   *minimum = *natural = requisition.width;
 534 }
 535
 536 static void
 537 gtk_offscreen_box_get_preferred_height (GtkWidget *widget,
 538                                         gint      *minimum,
 539                                         gint      *natural)
 540 {
 541   GtkRequisition requisition;
 542
 543   gtk_offscreen_box_size_request (widget, &requisition);
 544
 545   *minimum = *natural = requisition.height;
 546 }
 547
 548 static void
 549 gtk_offscreen_box_size_allocate (GtkWidget     *widget,
 550                                  GtkAllocation *allocation)
 551 {
 552   GtkOffscreenBox *offscreen_box;
 553   gint start_y;
 554   guint border_width;
 555
 556   offscreen_box = GTK_OFFSCREEN_BOX (widget);
 557
 558   gtk_widget_set_allocation (widget, allocation);
 559
 560   border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
 561
 562   if (gtk_widget_get_realized (widget))
 563     gdk_window_move_resize (gtk_widget_get_window (widget),
 564                             allocation->x + border_width,
 565                             allocation->y + border_width,
 566                             allocation->width - border_width * 2,
 567                             allocation->height - border_width * 2);
 568
 569   start_y = 0;
 570
 571   if (offscreen_box->child1 && gtk_widget_get_visible (offscreen_box->child1))
 572     {
 573       GtkRequisition child_requisition;
 574       GtkAllocation child_allocation;
 575
 576       gtk_widget_get_preferred_size (offscreen_box->child1,
 577                                      &child_requisition, NULL);
 578       child_allocation.x = child_requisition.width * (CHILD1_SIZE_SCALE - 1.0) / 2;
 579       child_allocation.y = start_y + child_requisition.height * (CHILD1_SIZE_SCALE - 1.0) / 2;
 580       child_allocation.width = MAX (1, (gint) allocation->width - 2 * border_width);
 581       child_allocation.height = child_requisition.height;
 582
 583       start_y += CHILD1_SIZE_SCALE * child_requisition.height;
 584
 585       if (gtk_widget_get_realized (widget))
 586         gdk_window_move_resize (offscreen_box->offscreen_window1,
 587                                 child_allocation.x,
 588                                 child_allocation.y,
 589                                 child_allocation.width,
 590                                 child_allocation.height);
 591
 592       child_allocation.x = child_allocation.y = 0;
 593       gtk_widget_size_allocate (offscreen_box->child1, &child_allocation);
 594     }
 595
 596   if (offscreen_box->child2 && gtk_widget_get_visible (offscreen_box->child2))
 597     {
 598       GtkRequisition child_requisition;
 599       GtkAllocation child_allocation;
 600
 601       gtk_widget_get_preferred_size (offscreen_box->child2,
 602                                      &child_requisition, NULL);
 603       child_allocation.x = child_requisition.width * (CHILD2_SIZE_SCALE - 1.0) / 2;
 604       child_allocation.y = start_y + child_requisition.height * (CHILD2_SIZE_SCALE - 1.0) / 2;
 605       child_allocation.width = MAX (1, (gint) allocation->width - 2 * border_width);
 606       child_allocation.height = child_requisition.height;
 607
 608       start_y += CHILD2_SIZE_SCALE * child_requisition.height;
 609
 610       if (gtk_widget_get_realized (widget))
 611         gdk_window_move_resize (offscreen_box->offscreen_window2,
 612                                 child_allocation.x,
 613                                 child_allocation.y,
 614                                 child_allocation.width,
 615                                 child_allocation.height);
 616
 617       child_allocation.x = child_allocation.y = 0;
 618       gtk_widget_size_allocate (offscreen_box->child2, &child_allocation);
 619     }
 620 }
 621
 622 static gboolean
 623 gtk_offscreen_box_damage (GtkWidget      *widget,
 624                           GdkEventExpose *event)
 625 {
 626   gdk_window_invalidate_rect (gtk_widget_get_window (widget),
 627                               NULL, FALSE);
 628
 629   return TRUE;
 630 }
 631
 632 static gboolean
 633 gtk_offscreen_box_draw (GtkWidget *widget,
 634                         cairo_t   *cr)
 635 {
 636   GtkOffscreenBox *offscreen_box = GTK_OFFSCREEN_BOX (widget);
 637   GdkWindow *window;
 638
 639   window = gtk_widget_get_window (widget);
 640   if (gtk_cairo_should_draw_window (cr, window))
 641     {
 642       cairo_surface_t *surface;
 643       GtkAllocation child_area;
 644
 645       if (offscreen_box->child1 && gtk_widget_get_visible (offscreen_box->child1))
 646         {
 647           surface = gdk_offscreen_window_get_surface (offscreen_box->offscreen_window1);
 648
 649           cairo_set_source_surface (cr, surface, 0, 0);
 650           cairo_paint (cr);
 651
 652           gtk_widget_get_allocation (offscreen_box->child1, &child_area);
 653           cairo_translate (cr, 0, child_area.height);
 654         }
 655
 656       if (offscreen_box->child2 && gtk_widget_get_visible (offscreen_box->child2))
 657         {
 658           surface = gdk_offscreen_window_get_surface (offscreen_box->offscreen_window2);
 659
 660           gtk_widget_get_allocation (offscreen_box->child2, &child_area);
 661
 662           /* transform */
 663           cairo_translate (cr, child_area.width / 2, child_area.height / 2);
 664           cairo_rotate (cr, offscreen_box->angle);
 665           cairo_translate (cr, -child_area.width / 2, -child_area.height / 2);
 666
 667           /* paint */
 668           cairo_set_source_surface (cr, surface, 0, 0);
 669           cairo_paint (cr);
 670         }
 671     }
 672   else if (gtk_cairo_should_draw_window (cr, offscreen_box->offscreen_window1))
 673     {
 674       gtk_render_background (gtk_widget_get_style_context (widget), cr,
 675                              0, 0,
 676
 677                              gdk_window_get_width (offscreen_box->offscreen_window1),
 678                              gdk_window_get_height (offscreen_box->offscreen_window1));
 679
 680       if (offscreen_box->child1)
 681         gtk_container_propagate_draw (GTK_CONTAINER (widget),
 682                                       offscreen_box->child1,
 683                                       cr);
 684     }
 685   else if (gtk_cairo_should_draw_window (cr, offscreen_box->offscreen_window2))
 686     {
 687       gtk_render_background (gtk_widget_get_style_context (widget), cr,
 688                              0, 0,
 689                              gdk_window_get_width (offscreen_box->offscreen_window2),
 690                              gdk_window_get_height (offscreen_box->offscreen_window2));
 691
 692       if (offscreen_box->child2)
 693         gtk_container_propagate_draw (GTK_CONTAINER (widget),
 694                                       offscreen_box->child2,
 695                                       cr);
 696     }
 697
 698   return FALSE;
 699 }