Pileus Git - ~andy/gtk/blob - gdk/gdkimage.c

   1 /* GDK - The GIMP Drawing Kit
   2  * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GTK+ Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 #include "config.h"
  28 #include <stdlib.h>
  29 #include <sys/types.h>
  30
  31 #include "gdk.h"                /* For gdk_flush() */
  32 #include "gdkimage.h"
  33 #include "gdkprivate.h"
  34 #include "gdkinternals.h"       /* For scratch_image code */
  35 #include "gdkalias.h"
  36
  37 /**
  38  * gdk_image_ref:
  39  * @image: a #GdkImage
  40  *
  41  * Deprecated function; use g_object_ref() instead.
  42  *
  43  * Return value: the image
  44  **/
  45 GdkImage *
  46 gdk_image_ref (GdkImage *image)
  47 {
  48   g_return_val_if_fail (GDK_IS_IMAGE (image), NULL);
  49
  50   return g_object_ref (image);
  51 }
  52
  53 /**
  54  * gdk_image_unref:
  55  * @image: a #GdkImage
  56  *
  57  * Deprecated function; use g_object_unref() instead.
  58  *
  59  **/
  60 void
  61 gdk_image_unref (GdkImage *image)
  62 {
  63   g_return_if_fail (GDK_IS_IMAGE (image));
  64
  65   g_object_unref (image);
  66 }
  67
  68 /**
  69  * gdk_image_get:
  70  * @drawable: a #GdkDrawable
  71  * @x: x coordinate in @window
  72  * @y: y coordinate in @window
  73  * @width: width of area in @window
  74  * @height: height of area in @window
  75  *
  76  * This is a deprecated wrapper for gdk_drawable_get_image();
  77  * gdk_drawable_get_image() should be used instead. Or even better: in
  78  * most cases gdk_pixbuf_get_from_drawable() is the most convenient
  79  * choice.
  80  *
  81  * Return value: a new #GdkImage or %NULL
  82  **/
  83 GdkImage*
  84 gdk_image_get (GdkWindow *drawable,
  85                gint       x,
  86                gint       y,
  87                gint       width,
  88                gint       height)
  89 {
  90   g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
  91   g_return_val_if_fail (x >= 0, NULL);
  92   g_return_val_if_fail (y >= 0, NULL);
  93   g_return_val_if_fail (width >= 0, NULL);
  94   g_return_val_if_fail (height >= 0, NULL);
  95
  96   return gdk_drawable_get_image (drawable, x, y, width, height);
  97 }
  98
  99 /**
 100  * gdk_image_set_colormap:
 101  * @image: a #GdkImage
 102  * @colormap: a #GdkColormap
 103  *
 104  * Sets the colormap for the image to the given colormap.  Normally
 105  * there's no need to use this function, images are created with the
 106  * correct colormap if you get the image from a drawable. If you
 107  * create the image from scratch, use the colormap of the drawable you
 108  * intend to render the image to.
 109  **/
 110 void
 111 gdk_image_set_colormap (GdkImage       *image,
 112                         GdkColormap    *colormap)
 113 {
 114   g_return_if_fail (GDK_IS_IMAGE (image));
 115   g_return_if_fail (GDK_IS_COLORMAP (colormap));
 116
 117   if (image->colormap != colormap)
 118     {
 119       if (image->colormap)
 120         g_object_unref (image->colormap);
 121
 122       image->colormap = colormap;
 123       g_object_ref (image->colormap);
 124     }
 125 }
 126
 127 /**
 128  * gdk_image_get_colormap:
 129  * @image: a #GdkImage
 130  *
 131  * Retrieves the colormap for a given image, if it exists.  An image
 132  * will have a colormap if the drawable from which it was created has
 133  * a colormap, or if a colormap was set explicitely with
 134  * gdk_image_set_colormap().
 135  *
 136  * Return value: colormap for the image
 137  **/
 138 GdkColormap *
 139 gdk_image_get_colormap (GdkImage *image)
 140 {
 141   g_return_val_if_fail (GDK_IS_IMAGE (image), NULL);
 142
 143   return image->colormap;
 144 }
 145
 146 /* We have N_REGION GDK_SCRATCH_IMAGE_WIDTH x GDK_SCRATCH_IMAGE_HEIGHT regions divided
 147  * up between n_images different images. possible_n_images gives
 148  * various divisors of N_REGIONS. The reason for allowing this
 149  * flexibility is that we want to create as few images as possible,
 150  * but we want to deal with the abberant systems that have a SHMMAX
 151  * limit less than
 152  *
 153  * GDK_SCRATCH_IMAGE_WIDTH * GDK_SCRATCH_IMAGE_HEIGHT * N_REGIONS * 4 (384k)
 154  *
 155  * (Are there any such?)
 156  */
 157 #define N_REGIONS 6
 158 static const int possible_n_images[] = { 1, 2, 3, 6 };
 159
 160 /* We allocate one GdkScratchImageInfo structure for each
 161  * depth where we are allocating scratch images. (Future: one
 162  * per depth, per display)
 163  */
 164 typedef struct _GdkScratchImageInfo GdkScratchImageInfo;
 165
 166 struct _GdkScratchImageInfo {
 167   gint depth;
 168
 169   gint n_images;
 170   GdkImage *static_image[N_REGIONS];
 171   gint static_image_idx;
 172
 173   /* In order to optimize filling fractions, we simultaneously fill in up
 174    * to three regions of size GDK_SCRATCH_IMAGE_WIDTH * GDK_SCRATCH_IMAGE_HEIGHT: one
 175    * for images that are taller than GDK_SCRATCH_IMAGE_HEIGHT / 2, and must
 176    * be tiled horizontally. One for images that are wider than
 177    * GDK_SCRATCH_IMAGE_WIDTH / 2 and must be tiled vertically, and a third
 178    * for images smaller than GDK_SCRATCH_IMAGE_HEIGHT / 2 x GDK_SCRATCH_IMAGE_WIDTH x 2
 179    * that we tile in horizontal rows.
 180    */
 181   gint horiz_idx;
 182   gint horiz_y;
 183   gint vert_idx;
 184   gint vert_x;
 185
 186   /* tile_y1 and tile_y2 define the horizontal band into
 187    * which we are tiling images. tile_x is the x extent to
 188    * which that is filled
 189    */
 190   gint tile_idx;
 191   gint tile_x;
 192   gint tile_y1;
 193   gint tile_y2;
 194
 195   GdkScreen *screen;
 196 };
 197
 198 static GSList *scratch_image_infos = NULL;
 199
 200 static gboolean
 201 allocate_scratch_images (GdkScratchImageInfo *info,
 202                          gint                 n_images,
 203                          gboolean             shared)
 204 {
 205   gint i;
 206
 207   for (i = 0; i < n_images; i++)
 208     {
 209       info->static_image[i] = _gdk_image_new_for_depth (info->screen,
 210                                                         shared ? GDK_IMAGE_SHARED : GDK_IMAGE_NORMAL,
 211                                                         NULL,
 212                                                         GDK_SCRATCH_IMAGE_WIDTH * (N_REGIONS / n_images),
 213                                                         GDK_SCRATCH_IMAGE_HEIGHT,
 214                                                         info->depth);
 215
 216       if (!info->static_image[i])
 217         {
 218           gint j;
 219
 220           for (j = 0; j < i; j++)
 221             g_object_unref (info->static_image[j]);
 222
 223           return FALSE;
 224         }
 225     }
 226
 227   return TRUE;
 228 }
 229
 230 static void
 231 scratch_image_info_display_closed (GdkDisplay          *display,
 232                                    gboolean             is_error,
 233                                    GdkScratchImageInfo *image_info)
 234 {
 235   gint i;
 236
 237   g_signal_handlers_disconnect_by_func (display,
 238                                         scratch_image_info_display_closed,
 239                                         image_info);
 240
 241   scratch_image_infos = g_slist_remove (scratch_image_infos, image_info);
 242
 243   for (i = 0; i < image_info->n_images; i++)
 244     g_object_unref (image_info->static_image[i]);
 245
 246   g_free (image_info);
 247 }
 248
 249 static GdkScratchImageInfo *
 250 scratch_image_info_for_depth (GdkScreen *screen,
 251                               gint       depth)
 252 {
 253   GSList *tmp_list;
 254   GdkScratchImageInfo *image_info;
 255   gint i;
 256
 257   tmp_list = scratch_image_infos;
 258   while (tmp_list)
 259     {
 260       image_info = tmp_list->data;
 261       if (image_info->depth == depth && image_info->screen == screen)
 262         return image_info;
 263
 264       tmp_list = tmp_list->next;
 265     }
 266
 267   image_info = g_new (GdkScratchImageInfo, 1);
 268
 269   image_info->depth = depth;
 270   image_info->screen = screen;
 271
 272   g_signal_connect (gdk_screen_get_display (screen), "closed",
 273                     G_CALLBACK (scratch_image_info_display_closed),
 274                     image_info);
 275
 276   /* Try to allocate as few possible shared images */
 277   for (i=0; i < G_N_ELEMENTS (possible_n_images); i++)
 278     {
 279       if (allocate_scratch_images (image_info, possible_n_images[i], TRUE))
 280         {
 281           image_info->n_images = possible_n_images[i];
 282           break;
 283         }
 284     }
 285
 286   /* If that fails, just allocate N_REGIONS normal images */
 287   if (i == G_N_ELEMENTS (possible_n_images))
 288     {
 289       allocate_scratch_images (image_info, N_REGIONS, FALSE);
 290       image_info->n_images = N_REGIONS;
 291     }
 292
 293   image_info->static_image_idx = 0;
 294
 295   image_info->horiz_y = GDK_SCRATCH_IMAGE_HEIGHT;
 296   image_info->vert_x = GDK_SCRATCH_IMAGE_WIDTH;
 297   image_info->tile_x = GDK_SCRATCH_IMAGE_WIDTH;
 298   image_info->tile_y1 = image_info->tile_y2 = GDK_SCRATCH_IMAGE_HEIGHT;
 299
 300   scratch_image_infos = g_slist_prepend (scratch_image_infos, image_info);
 301
 302   return image_info;
 303 }
 304
 305 /* Defining NO_FLUSH can cause inconsistent screen updates, but is useful
 306    for performance evaluation. */
 307
 308 #undef NO_FLUSH
 309
 310 #ifdef VERBOSE
 311 static gint sincelast;
 312 #endif
 313
 314 static gint
 315 alloc_scratch_image (GdkScratchImageInfo *image_info)
 316 {
 317   if (image_info->static_image_idx == N_REGIONS)
 318     {
 319 #ifndef NO_FLUSH
 320       gdk_flush ();
 321 #endif
 322 #ifdef VERBOSE
 323       g_print ("flush, %d puts since last flush\n", sincelast);
 324       sincelast = 0;
 325 #endif
 326       image_info->static_image_idx = 0;
 327
 328       /* Mark all regions that we might be filling in as completely
 329        * full, to force new tiles to be allocated for subsequent
 330        * images
 331        */
 332       image_info->horiz_y = GDK_SCRATCH_IMAGE_HEIGHT;
 333       image_info->vert_x = GDK_SCRATCH_IMAGE_WIDTH;
 334       image_info->tile_x = GDK_SCRATCH_IMAGE_WIDTH;
 335       image_info->tile_y1 = image_info->tile_y2 = GDK_SCRATCH_IMAGE_HEIGHT;
 336     }
 337   return image_info->static_image_idx++;
 338 }
 339
 340 /**
 341  * _gdk_image_get_scratch:
 342  * @screen: a #GdkScreen
 343  * @width: desired width
 344  * @height: desired height
 345  * @depth: depth of image
 346  * @x: X location within returned image of scratch image
 347  * @y: Y location within returned image of scratch image
 348  *
 349  * Allocates an image of size width/height, up to a maximum
 350  * of GDK_SCRATCH_IMAGE_WIDTHxGDK_SCRATCH_IMAGE_HEIGHT that is
 351  * suitable to use on @screen.
 352  *
 353  * Return value: a scratch image. This must be used by a
 354  *  call to gdk_image_put() before any other calls to
 355  *  _gdk_image_get_scratch()
 356  **/
 357 GdkImage *
 358 _gdk_image_get_scratch (GdkScreen   *screen,
 359                         gint         width,
 360                         gint         height,
 361                         gint         depth,
 362                         gint        *x,
 363                         gint        *y)
 364 {
 365   GdkScratchImageInfo *image_info;
 366   GdkImage *image;
 367   gint idx;
 368
 369   g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
 370
 371   image_info = scratch_image_info_for_depth (screen, depth);
 372
 373   if (width >= (GDK_SCRATCH_IMAGE_WIDTH >> 1))
 374     {
 375       if (height >= (GDK_SCRATCH_IMAGE_HEIGHT >> 1))
 376         {
 377           idx = alloc_scratch_image (image_info);
 378           *x = 0;
 379           *y = 0;
 380         }
 381       else
 382         {
 383           if (height + image_info->horiz_y > GDK_SCRATCH_IMAGE_HEIGHT)
 384             {
 385               image_info->horiz_idx = alloc_scratch_image (image_info);
 386               image_info->horiz_y = 0;
 387             }
 388           idx = image_info->horiz_idx;
 389           *x = 0;
 390           *y = image_info->horiz_y;
 391           image_info->horiz_y += height;
 392         }
 393     }
 394   else
 395     {
 396       if (height >= (GDK_SCRATCH_IMAGE_HEIGHT >> 1))
 397         {
 398           if (width + image_info->vert_x > GDK_SCRATCH_IMAGE_WIDTH)
 399             {
 400               image_info->vert_idx = alloc_scratch_image (image_info);
 401               image_info->vert_x = 0;
 402             }
 403           idx = image_info->vert_idx;
 404           *x = image_info->vert_x;
 405           *y = 0;
 406           /* using 3 and -4 would be slightly more efficient on 32-bit machines
 407              with > 1bpp displays */
 408           image_info->vert_x += (width + 7) & -8;
 409         }
 410       else
 411         {
 412           if (width + image_info->tile_x > GDK_SCRATCH_IMAGE_WIDTH)
 413             {
 414               image_info->tile_y1 = image_info->tile_y2;
 415               image_info->tile_x = 0;
 416             }
 417           if (height + image_info->tile_y1 > GDK_SCRATCH_IMAGE_HEIGHT)
 418             {
 419               image_info->tile_idx = alloc_scratch_image (image_info);
 420               image_info->tile_x = 0;
 421               image_info->tile_y1 = 0;
 422               image_info->tile_y2 = 0;
 423             }
 424           if (height + image_info->tile_y1 > image_info->tile_y2)
 425             image_info->tile_y2 = height + image_info->tile_y1;
 426           idx = image_info->tile_idx;
 427           *x = image_info->tile_x;
 428           *y = image_info->tile_y1;
 429           image_info->tile_x += (width + 7) & -8;
 430         }
 431     }
 432   image = image_info->static_image[idx * image_info->n_images / N_REGIONS];
 433   *x += GDK_SCRATCH_IMAGE_WIDTH * (idx % (N_REGIONS / image_info->n_images));
 434 #ifdef VERBOSE
 435   g_print ("index %d, x %d, y %d (%d x %d)\n", idx, *x, *y, width, height);
 436   sincelast++;
 437 #endif
 438   return image;
 439 }
 440
 441 GdkImage*
 442 gdk_image_new (GdkImageType  type,
 443                GdkVisual    *visual,
 444                gint          width,
 445                gint          height)
 446 {
 447   return _gdk_image_new_for_depth (gdk_visual_get_screen (visual), type,
 448                                    visual, width, height, -1);
 449 }
 450
 451 #define __GDK_IMAGE_C__
 452 #include "gdkaliasdef.c"