src/loading.c

   1 /*
   2  * This program is free software; you can redistribute it and/or
   3  * modify it under the terms of the GNU General Public License
   4  * as published by the Free Software Foundation; either version 2
   5  * of the License, or (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  15  *
  16  * See the COPYING file for license information.
  17  *
  18  * Guillaume Chazarain <guichaz@yahoo.fr>
  19  */
  20
  21 /***********************************
  22  * Loading and unloading of images *
  23  ***********************************/
  24
  25 #include <stdio.h>              /* FILE, fopen(), fread(), fclose(), perror() */
  26 #include <signal.h>             /* signal(), SIG_DFL, SIGSEGV */
  27 #include <string.h>             /* strlen(), strrchr() */
  28
  29 #include "gliv.h"
  30 #include "loading.h"
  31 #include "options.h"
  32 #include "gliv-image.h"
  33 #include "messages.h"
  34 #include "str_utils.h"
  35 #include "formats.h"
  36 #include "params.h"
  37 #include "files_list.h"
  38 #include "textures.h"
  39 #include "thread.h"
  40 #include "decompression.h"
  41 #include "thumbnails.h"
  42 #include "rendering.h"
  43 #include "tree_browser.h"
  44
  45 extern rt_struct *rt;
  46 extern options_struct *options;
  47 extern GlivImage *current_image;
  48
  49 /* Used to know at any time if we are loading an image. */
  50 static gchar *loading_filename = NULL;
  51
  52 /*
  53  * Used to be quiet when we try to load files
  54  * not explicitly requested by the user.
  55  */
  56 static gint quiet = 0;
  57
  58 void start_quiet(void)
  59 {
  60     quiet++;
  61 }
  62
  63 void stop_quiet(void)
  64 {
  65     quiet--;
  66 }
  67
  68 const gchar *currently_loading(void)
  69 {
  70     return loading_filename;
  71 }
  72
  73 static void segv_handler(gint sig)
  74 {
  75     const gchar *sig_str;
  76
  77     signal(sig, SIG_DFL);
  78     sig_str = g_strsignal(sig);
  79
  80     if (loading_filename == NULL)
  81         g_printerr(_("%s not while loading an image\n"), sig_str);
  82     else
  83         g_printerr(_("%s while loading %s\n"), sig_str, loading_filename);
  84
  85     raise(sig);
  86 }
  87
  88 /* Called when the first image is loaded. */
  89 void install_segv_handler(void)
  90 {
  91     signal(SIGSEGV, segv_handler);
  92 }
  93
  94 void fill_ident(GlivImage * im)
  95 {
  96     gchar *alpha_str = NULL;
  97     gint im_nr;
  98
  99     g_free(im->ident);
 100
 101     if (im->has_alpha)
 102         alpha_str = g_strconcat(" (", _("alpha channel"), ")", NULL);
 103     else
 104         alpha_str = g_strdup("");
 105
 106     im_nr = get_image_number(im);
 107     im->ident = g_strdup_printf("%s (%u/%u)%s",
 108                                 im->node ?
 109                                 filename_to_utf8(im->node->data) : "",
 110                                 im_nr + 1, get_list_length(), alpha_str);
 111
 112     g_free(alpha_str);
 113 }
 114
 115 const gchar *get_extension(const gchar * filename)
 116 {
 117     const gchar *ext;
 118     const gchar *basename;
 119
 120     basename = strrchr(filename, '/');
 121     if (basename == NULL)
 122         basename = filename;
 123     else
 124         basename++;
 125
 126     ext = strrchr(basename, '.');
 127     if (ext != NULL)
 128         /* Skip the '.' */
 129         ext++;
 130
 131     return ext;
 132 }
 133
 134 #define LOADING_ERROR if (!quiet) g_printerr
 135
 136 static loader_t get_decompressor(const gchar * filename, gint ext_len)
 137 {
 138     const struct format *res;
 139
 140     /* We want the image extension between image_ext_start and image_ext_end. */
 141     const gchar *image_ext_end = filename + strlen(filename) - ext_len - 1;
 142     const gchar *image_ext_start = image_ext_end - 1;
 143
 144     gint image_ext_length = 0;
 145     gchar *image_ext;
 146
 147     while (image_ext_start > filename && *image_ext_start != '.') {
 148         image_ext_length++;
 149         image_ext_start--;
 150     }
 151
 152     image_ext = g_strndup(image_ext_start + 1, image_ext_length);
 153     res = ext_to_loader(image_ext, image_ext_length);
 154
 155     g_free(image_ext);
 156
 157     if (res == NULL) {
 158         LOADING_ERROR(_("%s: unknown decompressed extension\n"),
 159                       filename_to_utf8(filename));
 160         return LOADER_NONE;
 161     }
 162
 163     switch (res->loader) {
 164     case LOADER_DECOMP:
 165         LOADING_ERROR(_("%s: image cannot be compressed twice\n"),
 166                       filename_to_utf8(filename));
 167         return LOADER_NONE;
 168
 169     case LOADER_PIXBUF:
 170         return LOADER_DECOMP_PIXBUF;
 171
 172     case LOADER_DOT_GLIV:
 173         return LOADER_DECOMP_DOT_GLIV;
 174
 175     default:
 176         return LOADER_NONE;
 177     }
 178 }
 179
 180 loader_t get_loader(const gchar * filename)
 181 {
 182     const struct format *res;
 183     const gchar *ext;
 184     gint ext_len;
 185
 186     ext = get_extension(filename);
 187     if (ext == NULL) {
 188         LOADING_ERROR(_("%s: unknown extension (none)\n"),
 189                       filename_to_utf8(filename));
 190         return LOADER_NONE;
 191     }
 192
 193     ext_len = strlen(ext);
 194     res = ext_to_loader(ext, ext_len);
 195
 196     if (res == NULL) {
 197         LOADING_ERROR(_("%s: unknown extension\n"), filename_to_utf8(filename));
 198         return LOADER_NONE;
 199     }
 200
 201     if (res->loader == LOADER_DECOMP)
 202         return get_decompressor(filename, ext_len);
 203
 204     return res->loader;
 205 }
 206
 207 #if 0
 208 /*
 209  * We used to blacken image pixels with alpha == 0.
 210  * These pixels are invisible but may alter the bilinear filtering.
 211  * We have stopped doing it since the time lost is too big for the benefit.
 212  */
 213 static void clean_alpha(GdkPixbuf * pixbuf)
 214 {
 215     guchar *pixel, *end;
 216
 217     pixel = gdk_pixbuf_get_pixels(pixbuf);
 218     end = pixel + pixels_size(pixels_size);
 219
 220     for (; pixel < end; pixel += 4) {
 221         if (pixel[3] == 0)
 222             /*
 223              * alpha == 0
 224              * This is not valid C since a cast cannot be a lvalue but...
 225              */
 226             *((guint32 *) pixel) = 0;
 227     }
 228 }
 229 #endif
 230
 231 void set_loading(const gchar * filename)
 232 {
 233     /* Used if there is a segfault. */
 234     g_free(loading_filename);
 235     loading_filename = g_strdup(filename);
 236     update_current_image_status(FALSE);
 237
 238     if (filename == NULL)
 239         /*
 240          * Do it, now that we are no more in
 241          * the currently_loading() case
 242          */
 243         load_later();
 244 }
 245
 246 /* Wrapper: two args -> one arg. */
 247 typedef struct {
 248     const gchar *filename;
 249     GError **error;
 250 } fname_error;
 251
 252 static GdkPixbuf *load_gdk_pixbuf(fname_error * param)
 253 {
 254     GdkPixbuf *pixbuf = NULL;
 255     loader_t loader;
 256
 257     loader = get_loader(param->filename);
 258     if (loader == LOADER_DECOMP_PIXBUF)
 259         pixbuf = load_compressed_pixbuf(param->filename, param->error);
 260
 261     if (*param->error)
 262         return pixbuf;
 263
 264     if (pixbuf == NULL)
 265         pixbuf = gdk_pixbuf_new_from_file(param->filename, param->error);
 266
 267     return pixbuf;
 268 }
 269
 270 static GdkPixbuf *load_gdk_pixbuf_threaded(const gchar * filename,
 271                                            GError ** error)
 272 {
 273     fname_error *param;
 274     GdkPixbuf *pixbuf;
 275
 276     param = g_new(fname_error, 1);
 277     param->filename = filename;
 278     param->error = (error == NULL) ? g_new(GError *, 1) : error;
 279
 280     *param->error = NULL;
 281     pixbuf = do_threaded((GThreadFunc) load_gdk_pixbuf, param);
 282
 283     if (pixbuf == NULL) {
 284         if (error == NULL) {
 285             /*
 286              * The caller won't handle the error, handle it here
 287              */
 288             if (*param->error != NULL)
 289                 DIALOG_MSG("%s", (*param->error)->message);
 290             else
 291                 DIALOG_MSG(_("Cannot load %s"), filename);
 292         }
 293     } else
 294         add_thumbnail(filename, pixbuf);
 295
 296     g_free(param);
 297     return pixbuf;
 298 }
 299
 300 gint pixels_size(GdkPixbuf * pixbuf)
 301 {
 302     /* The last rowstride may not be full. */
 303     gint w = gdk_pixbuf_get_width(pixbuf);
 304     gint h = gdk_pixbuf_get_height(pixbuf);
 305     gint rs = gdk_pixbuf_get_rowstride(pixbuf);
 306     gint nb_chan = gdk_pixbuf_get_n_channels(pixbuf);
 307     gint bps = gdk_pixbuf_get_bits_per_sample(pixbuf);
 308
 309     return ((h - 1) * rs + w * ((nb_chan * bps + 7) / 8));
 310 }
 311
 312 G_GNUC_PURE static gint nb_maps(gint dim)
 313 {
 314     gint ret = 1;
 315
 316     while (dim > rt->max_texture_size) {
 317         dim *= MIPMAP_RATIO;
 318         ret++;
 319     }
 320
 321     return ret;
 322 }
 323
 324 GlivImage *make_gliv_image(GdkPixbuf * pixbuf)
 325 {
 326     GlivImage *im;
 327
 328     im = gliv_image_new();
 329     im->ident = NULL;
 330     im->number = -1;
 331     im->node = NULL;
 332     im->first_image = (current_image == NULL);
 333
 334     im->width = gdk_pixbuf_get_width(pixbuf);
 335     im->height = gdk_pixbuf_get_height(pixbuf);
 336     im->has_alpha = gdk_pixbuf_get_has_alpha(pixbuf);
 337
 338     if (options->mipmap) {
 339         gint nb_w = nb_maps(im->width);
 340         gint nb_h = nb_maps(im->height);
 341         im->nb_maps = MIN(nb_w, nb_h);
 342     } else
 343         im->nb_maps = 1;
 344
 345     im->maps = g_new(texture_map, im->nb_maps);
 346     im->maps[0].pixbuf = pixbuf;
 347
 348 #if 0
 349     if (im->has_alpha)
 350         clean_alpha(pixbuf);
 351 #endif
 352
 353     create_maps(im);
 354     return im;
 355 }
 356
 357 GlivImage *load_file(const gchar * filename, GError ** error)
 358 {
 359     GdkPixbuf *loaded_image;
 360     GlivImage *im = NULL;
 361
 362     set_loading(filename_to_utf8(filename));
 363
 364     loaded_image = load_gdk_pixbuf_threaded(filename, error);
 365     if (loaded_image != NULL)
 366         im = make_gliv_image(loaded_image);
 367
 368     set_loading(NULL);
 369
 370     return im;
 371 }