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 #include <GL/gl.h>
  29
  30 #include "gliv.h"
  31 #include "loading.h"
  32 #include "options.h"
  33 #include "gliv_image.h"
  34 #include "messages.h"
  35 #include "gl_widget.h"
  36 #include "str_utils.h"
  37 #include "formats.h"
  38 #include "params.h"
  39 #include "files_list.h"
  40 #include "textures.h"
  41 #include "windows.h"
  42 #include "thread.h"
  43 #include "decompression.h"
  44
  45 extern rt_struct *rt;
  46 extern options_struct *options;
  47
  48 /* Used to know at any time if we are loading an image. */
  49 static const gchar *loading_filename = NULL;
  50
  51 gboolean is_loading(void)
  52 {
  53     return loading_filename != NULL;
  54 }
  55
  56 void destroy_image(gliv_image * im)
  57 {
  58     gint level;
  59     texture_map *map;
  60
  61     if (im != NULL) {
  62         for (level = 0; level < im->nb_maps; level++) {
  63             map = im->maps + level;
  64
  65             glDeleteTextures(map->nb_tiles, map->tex_ids);
  66             g_free(map->tex_ids);
  67
  68             glDeleteLists(map->list, map->nb_tiles);
  69             g_free(map->tiles);
  70         }
  71
  72         g_free(im->maps);
  73         g_free(im->ident);
  74         g_free(im);
  75
  76         report_opengl_errors();
  77     }
  78 }
  79
  80 static void segv_handler(gint sig)
  81 {
  82     const gchar *sig_str;
  83
  84     signal(sig, SIG_DFL);
  85     sig_str = g_strsignal(sig);
  86
  87     if (loading_filename == NULL)
  88         ERROR_MSG(_("%s not while loading an image\n"), sig_str);
  89     else
  90         ERROR_MSG(_("%s while loading %s\n"),
  91                   sig_str, filename_to_utf8(loading_filename));
  92
  93     raise(sig);
  94 }
  95
  96 /* Called when the first image is loaded. */
  97 void install_segv_handler(void)
  98 {
  99     signal(SIGSEGV, segv_handler);
 100 }
 101
 102 void fill_ident(gliv_image * im)
 103 {
 104     gchar *alpha_str;
 105
 106     g_free(im->ident);
 107
 108     alpha_str = im->has_alpha ? _("alpha channel") : _("no alpha channel");
 109
 110     im->ident = g_strdup_printf("%s (%u/%u) (%s)",
 111                                 filename_to_utf8(im->node->data),
 112                                 im->number + 1, get_list_length(), 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 static loader_t get_decompressor(const gchar * filename, gint ext_len)
 135 {
 136     const struct format *res;
 137
 138     /* We want the image extension between image_ext_start and image_ext_end. */
 139     const gchar *image_ext_end = filename + strlen(filename) - ext_len - 1;
 140     const gchar *image_ext_start = image_ext_end - 1;
 141
 142     gint image_ext_length = 0;
 143     gchar *image_ext;
 144
 145     while (image_ext_start > filename && *image_ext_start != '.') {
 146         image_ext_length++;
 147         image_ext_start--;
 148     }
 149
 150     image_ext = g_strndup(image_ext_start + 1, image_ext_length);
 151     res = ext_to_loader(image_ext, image_ext_length);
 152
 153     g_free(image_ext);
 154
 155     if (res == NULL) {
 156         ERROR_MSG(_("%s: unknown decompressed extension\n"),
 157                   filename_to_utf8(filename));
 158         return LOADER_NONE;
 159     }
 160
 161     switch (res->loader) {
 162     case LOADER_DECOMP:
 163         ERROR_MSG(_("%s: image cannot be compressed twice\n"),
 164                   filename_to_utf8(filename));
 165         return LOADER_NONE;
 166
 167     case LOADER_PIXBUF:
 168         return LOADER_DECOMP_PIXBUF;
 169
 170     case LOADER_DOT_GLIV:
 171         return LOADER_DECOMP_DOT_GLIV;
 172
 173     default:
 174         return LOADER_NONE;
 175     }
 176 }
 177
 178 loader_t get_loader(const gchar * filename)
 179 {
 180     const struct format *res;
 181     const gchar *ext;
 182     gint ext_len;
 183
 184     ext = get_extension(filename);
 185     if (ext == NULL) {
 186         ERROR_MSG(_("%s: unknown extension (none)\n"),
 187                   filename_to_utf8(filename));
 188         return LOADER_NONE;
 189     }
 190
 191     ext_len = strlen(ext);
 192     res = ext_to_loader(ext, ext_len);
 193
 194     if (res == NULL) {
 195         ERROR_MSG(_("%s: unknown extension\n"), filename_to_utf8(filename));
 196         return LOADER_NONE;
 197     }
 198
 199     if (res->loader == LOADER_DECOMP)
 200         return get_decompressor(filename, ext_len);
 201
 202     return res->loader;
 203 }
 204
 205 #if 0
 206 /*
 207  * We used to blacken image pixels with alpha == 0.
 208  * These pixels are invisible but may alter the bilinear filtering.
 209  * We have stopped doing it since the time lost is too big for the benefit.
 210  */
 211 static void clean_alpha(GdkPixbuf * pixbuf)
 212 {
 213     guchar *pixel, *end;
 214
 215     pixel = gdk_pixbuf_get_pixels(pixbuf);
 216     end = pixel + gdk_pixbuf_get_rowstride(pixbuf) *
 217         gdk_pixbuf_get_height(pixbuf);
 218
 219     for (; pixel < end; pixel += 4) {
 220         if (pixel[3] == 0)
 221             /*
 222              * alpha == 0
 223              * This is not valid C since a cast cannot be a lvalue but...
 224              */
 225             *((guint32 *) pixel) = 0;
 226     }
 227 }
 228 #endif
 229
 230 static void set_loading(const gchar * filename)
 231 {
 232     /* Used if there is a segfault. */
 233     loading_filename = filename;
 234
 235     set_loading_entry(filename);
 236 }
 237
 238 /* Wrapper: two args -> one arg. */
 239 typedef struct {
 240     const gchar *filename;
 241     GError **error;
 242 } fname_error;
 243
 244 static GdkPixbuf *load_gdk_pixbuf(fname_error * param)
 245 {
 246     GdkPixbuf *pixbuf = NULL;
 247     loader_t loader;
 248
 249     loader = get_loader(param->filename);
 250     if (loader == LOADER_DECOMP_PIXBUF)
 251         pixbuf = load_compressed_pixbuf(param->filename, param->error);
 252
 253     if (*param->error)
 254         return pixbuf;
 255
 256     if (pixbuf == NULL)
 257         pixbuf = gdk_pixbuf_new_from_file(param->filename, param->error);
 258
 259     return pixbuf;
 260 }
 261
 262 GdkPixbuf *load_gdk_pixbuf_threaded(const gchar * filename)
 263 {
 264     fname_error *param;
 265     GdkPixbuf *pixbuf;
 266
 267     param = g_new(fname_error, 1);
 268     param->filename = filename;
 269     param->error = g_new(GError *, 1);
 270     *param->error = NULL;
 271
 272     pixbuf = do_threaded((GThreadFunc) load_gdk_pixbuf, param);
 273
 274     if (pixbuf == NULL) {
 275         if (*param->error != NULL)
 276             DIALOG_MSG("%s", (*param->error)->message);
 277         else
 278             DIALOG_MSG(_("Cannot load %s"), filename);
 279     }
 280
 281     return pixbuf;
 282 }
 283
 284 G_GNUC_PURE static gint nb_maps(gint dim)
 285 {
 286     gint ret = 1;
 287
 288     while (dim > rt->max_texture_size) {
 289         dim *= MIPMAP_RATIO;
 290         ret++;
 291     }
 292
 293     return ret;
 294 }
 295
 296 gliv_image *load_file(const gchar * filename)
 297 {
 298     gliv_image *im;
 299     GdkPixbuf *loaded_image;
 300
 301     set_loading(filename);
 302
 303     loaded_image = load_gdk_pixbuf_threaded(filename);
 304     if (loaded_image == NULL) {
 305         /* Loading failed. */
 306         set_loading(NULL);
 307         return NULL;
 308     }
 309
 310     im = g_new(gliv_image, 1);
 311     im->ident = NULL;
 312
 313     im->width = gdk_pixbuf_get_width(loaded_image);
 314     im->height = gdk_pixbuf_get_height(loaded_image);
 315     im->has_alpha = gdk_pixbuf_get_has_alpha(loaded_image);
 316
 317     if (options->mipmap) {
 318         gint nb_w = nb_maps(im->width);
 319         gint nb_h = nb_maps(im->height);
 320         im->nb_maps = MIN(nb_w, nb_h);
 321     } else
 322         im->nb_maps = 1;
 323
 324     im->maps = g_new(texture_map, im->nb_maps);
 325     im->maps[0].map_init = g_new(loading_data, 1);
 326     im->maps[0].map_init->pixbuf = loaded_image;
 327
 328 #if 0
 329     if (im->has_alpha)
 330         clean_alpha(loaded_image);
 331 #endif
 332
 333     create_maps(im);
 334
 335     /* If there is a segfault it won't be because of the loading. */
 336     set_loading(NULL);
 337
 338     return im;
 339 }