src/viktmsmapsource.c

   1 /* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
   2 /*
   3  * viking
   4  * Copyright (C) 2010, Guilhem Bonnefille <guilhem.bonnefille@gmail.com>
   5  *
   6  * viking is free software: you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * viking is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  14  * See the GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20  /**
  21   * SECTION:viktmsmapsource
  22   * @short_description: the class for TMS oriented map sources
  23   *
  24   * The #VikTmsMapSource class handles TMS oriented map sources.
  25   *
  26   * The tiles are in 'equirectangular'.
  27   * http://en.wikipedia.org/wiki/Equirectangular_projection
  28   *
  29   * Such service is also a type of TMS (Tile Map Service) as defined in
  30   * OSGeo's wiki.
  31   * http://wiki.osgeo.org/wiki/Tile_Map_Service_Specification
  32   * Following this specification, the protocol handled by this class
  33   * follows the global-geodetic profile.
  34   */
  35
  36 #ifdef HAVE_CONFIG_H
  37 #include "config.h"
  38 #endif
  39
  40 #ifdef HAVE_MATH_H
  41 #include <math.h>
  42 #endif
  43
  44 #include "globals.h"
  45 #include "viktmsmapsource.h"
  46
  47 static gboolean _coord_to_mapcoord ( VikMapSource *self, const VikCoord *src, gdouble xzoom, gdouble yzoom, MapCoord *dest );
  48 static void _mapcoord_to_center_coord ( VikMapSource *self, MapCoord *src, VikCoord *dest );
  49 static gboolean _supports_download_only_new (VikMapSource *self );
  50
  51 static gchar *_get_uri( VikMapSourceDefault *self, MapCoord *src );
  52 static gchar *_get_hostname( VikMapSourceDefault *self );
  53 static DownloadMapOptions *_get_download_options( VikMapSourceDefault *self );
  54
  55 typedef struct _VikTmsMapSourcePrivate VikTmsMapSourcePrivate;
  56 struct _VikTmsMapSourcePrivate
  57 {
  58   gchar *hostname;
  59   gchar *url;
  60   DownloadMapOptions options;
  61 };
  62
  63 #define VIK_TMS_MAP_SOURCE_PRIVATE(o)  (G_TYPE_INSTANCE_GET_PRIVATE ((o), VIK_TYPE_TMS_MAP_SOURCE, VikTmsMapSourcePrivate))
  64
  65 /* properties */
  66 enum
  67 {
  68   PROP_0,
  69
  70   PROP_HOSTNAME,
  71   PROP_URL,
  72   PROP_REFERER,
  73   PROP_FOLLOW_LOCATION,
  74   PROP_CHECK_FILE_SERVER_TIME,
  75 };
  76
  77 G_DEFINE_TYPE (VikTmsMapSource, vik_tms_map_source, VIK_TYPE_MAP_SOURCE_DEFAULT);
  78
  79 static void
  80 vik_tms_map_source_init (VikTmsMapSource *self)
  81 {
  82   /* initialize the object here */
  83   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
  84
  85   priv->hostname = NULL;
  86   priv->url = NULL;
  87   priv->options.referer = NULL;
  88   priv->options.follow_location = 0;
  89   priv->options.check_file = a_check_map_file;
  90   priv->options.check_file_server_time = FALSE;
  91
  92   g_object_set (G_OBJECT (self),
  93                 "tilesize-x", 256,
  94                 "tilesize-y", 256,
  95                 "drawmode", VIK_VIEWPORT_DRAWMODE_LATLON,
  96                 NULL);
  97 }
  98
  99 static void
 100 vik_tms_map_source_finalize (GObject *object)
 101 {
 102   VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
 103   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
 104
 105   g_free (priv->hostname);
 106   priv->hostname = NULL;
 107   g_free (priv->url);
 108   priv->url = NULL;
 109   g_free (priv->options.referer);
 110   priv->options.referer = NULL;
 111
 112   G_OBJECT_CLASS (vik_tms_map_source_parent_class)->finalize (object);
 113 }
 114
 115 static void
 116 vik_tms_map_source_set_property (GObject      *object,
 117                                     guint         property_id,
 118                                     const GValue *value,
 119                                     GParamSpec   *pspec)
 120 {
 121   VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
 122   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
 123
 124   switch (property_id)
 125     {
 126     case PROP_HOSTNAME:
 127       g_free (priv->hostname);
 128       priv->hostname = g_value_dup_string (value);
 129       break;
 130
 131     case PROP_URL:
 132       g_free (priv->url);
 133       priv->url = g_value_dup_string (value);
 134       break;
 135
 136     case PROP_REFERER:
 137       g_free (priv->options.referer);
 138       priv->options.referer = g_value_dup_string (value);
 139       break;
 140
 141     case PROP_FOLLOW_LOCATION:
 142       priv->options.follow_location = g_value_get_long (value);
 143       break;
 144
 145     case PROP_CHECK_FILE_SERVER_TIME:
 146       priv->options.check_file_server_time = g_value_get_boolean (value);
 147       break;
 148
 149     default:
 150       /* We don't have any other property... */
 151       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
 152       break;
 153     }
 154 }
 155
 156 static void
 157 vik_tms_map_source_get_property (GObject    *object,
 158                                     guint       property_id,
 159                                     GValue     *value,
 160                                     GParamSpec *pspec)
 161 {
 162   VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
 163   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
 164
 165   switch (property_id)
 166     {
 167     case PROP_HOSTNAME:
 168       g_value_set_string (value, priv->hostname);
 169       break;
 170
 171     case PROP_URL:
 172       g_value_set_string (value, priv->url);
 173       break;
 174
 175     case PROP_REFERER:
 176       g_value_set_string (value, priv->options.referer);
 177       break;
 178
 179     case PROP_FOLLOW_LOCATION:
 180       g_value_set_long (value, priv->options.follow_location);
 181       break;
 182
 183     case PROP_CHECK_FILE_SERVER_TIME:
 184       g_value_set_boolean (value, priv->options.check_file_server_time);
 185       break;
 186
 187     default:
 188       /* We don't have any other property... */
 189       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
 190       break;
 191     }
 192 }
 193
 194 static void
 195 vik_tms_map_source_class_init (VikTmsMapSourceClass *klass)
 196 {
 197         GObjectClass* object_class = G_OBJECT_CLASS (klass);
 198         VikMapSourceClass* grandparent_class = VIK_MAP_SOURCE_CLASS (klass);
 199         VikMapSourceDefaultClass* parent_class = VIK_MAP_SOURCE_DEFAULT_CLASS (klass);
 200         GParamSpec *pspec = NULL;
 201
 202         object_class->set_property = vik_tms_map_source_set_property;
 203     object_class->get_property = vik_tms_map_source_get_property;
 204
 205         /* Overiding methods */
 206         grandparent_class->coord_to_mapcoord =        _coord_to_mapcoord;
 207         grandparent_class->mapcoord_to_center_coord = _mapcoord_to_center_coord;
 208         grandparent_class->supports_download_only_new = _supports_download_only_new;
 209
 210         parent_class->get_uri = _get_uri;
 211         parent_class->get_hostname = _get_hostname;
 212         parent_class->get_download_options = _get_download_options;
 213
 214         pspec = g_param_spec_string ("hostname",
 215                                      "Hostname",
 216                                      "The hostname of the map server",
 217                                      "<no-set>" /* default value */,
 218                                      G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 219         g_object_class_install_property (object_class, PROP_HOSTNAME, pspec);
 220
 221         pspec = g_param_spec_string ("url",
 222                                      "URL",
 223                                      "The template of the tiles' URL",
 224                                      "<no-set>" /* default value */,
 225                                      G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 226         g_object_class_install_property (object_class, PROP_URL, pspec);
 227
 228         pspec = g_param_spec_string ("referer",
 229                                      "Referer",
 230                                      "The REFERER string to use in HTTP request",
 231                                      NULL /* default value */,
 232                                      G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 233         g_object_class_install_property (object_class, PROP_REFERER, pspec);
 234
 235         pspec = g_param_spec_long ("follow-location",
 236                                    "Follow location",
 237                                "Specifies the number of retries to follow a redirect while downloading a page",
 238                                0  /* minimum value */,
 239                                G_MAXLONG /* maximum value */,
 240                                0  /* default value */,
 241                                G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 242         g_object_class_install_property (object_class, PROP_FOLLOW_LOCATION, pspec);
 243
 244         pspec = g_param_spec_boolean ("check-file-server-time",
 245                                       "Check file server time",
 246                                   "Age of current cache before redownloading tile",
 247                                   FALSE  /* default value */,
 248                                   G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 249         g_object_class_install_property (object_class, PROP_CHECK_FILE_SERVER_TIME, pspec);
 250
 251         g_type_class_add_private (klass, sizeof (VikTmsMapSourcePrivate));
 252
 253         object_class->finalize = vik_tms_map_source_finalize;
 254 }
 255
 256 /* 1 << (x) is like a 2**(x) */
 257 #define GZ(x) ((1<<(x)))
 258
 259 static const gdouble scale_mpps[] = { GZ(0), GZ(1), GZ(2), GZ(3), GZ(4), GZ(5), GZ(6), GZ(7), GZ(8), GZ(9),
 260                                            GZ(10), GZ(11), GZ(12), GZ(13), GZ(14), GZ(15), GZ(16), GZ(17) };
 261
 262 static const gint num_scales = (sizeof(scale_mpps) / sizeof(scale_mpps[0]));
 263
 264 static const gdouble scale_neg_mpps[] = { 1.0/GZ(0), 1.0/GZ(1), 1.0/GZ(2), 1.0/GZ(3) };
 265 static const gint num_scales_neg = (sizeof(scale_neg_mpps) / sizeof(scale_neg_mpps[0]));
 266
 267 #define ERROR_MARGIN 0.01
 268 static gint tms_zoom ( gdouble mpp ) {
 269   gint i;
 270   for ( i = 0; i < num_scales; i++ ) {
 271     if ( ABS(scale_mpps[i] - mpp) < ERROR_MARGIN ) {
 272       return i;
 273     }
 274   }
 275   for ( i = 0; i < num_scales_neg; i++ ) {
 276     if ( ABS(scale_neg_mpps[i] - mpp) < 0.000001 ) {
 277       return -i;
 278     }
 279   }
 280
 281   return 255;
 282 }
 283
 284 gboolean
 285 _supports_download_only_new (VikMapSource *self)
 286 {
 287         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), FALSE);
 288
 289     VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 290
 291         return priv->options.check_file_server_time;
 292 }
 293
 294 static gboolean
 295 _coord_to_mapcoord ( VikMapSource *self, const VikCoord *src, gdouble xzoom, gdouble yzoom, MapCoord *dest )
 296 {
 297   g_assert ( src->mode == VIK_COORD_LATLON );
 298
 299   if ( xzoom != yzoom )
 300     return FALSE;
 301
 302   dest->scale = tms_zoom ( xzoom );
 303   if ( dest->scale == 255 )
 304     return FALSE;
 305
 306   /* Note : GZ(17) / xzoom / 2 = number of tile on Y axis */
 307         g_debug("%s: xzoom=%f yzoom=%f -> %f", __FUNCTION__,
 308           xzoom, yzoom, GZ(17) / xzoom / 2);
 309   dest->x = floor((src->east_west + 180) / 180 * GZ(17) / xzoom / 2);
 310   /* We should restore logic of viking:
 311    * tile index on Y axis follow a screen logic (top -> down)
 312    */
 313   dest->y = floor((180 - (src->north_south + 90)) / 180 * GZ(17) / xzoom / 2);
 314   dest->z = 0;
 315   g_debug("%s: %f,%f -> %d,%d", __FUNCTION__,
 316           src->east_west, src->north_south, dest->x, dest->y);
 317   return TRUE;
 318 }
 319
 320 static void
 321 _mapcoord_to_center_coord ( VikMapSource *self, MapCoord *src, VikCoord *dest )
 322 {
 323   gdouble socalled_mpp;
 324   if (src->scale >= 0)
 325     socalled_mpp = GZ(src->scale);
 326   else
 327     socalled_mpp = 1.0/GZ(-src->scale);
 328   dest->mode = VIK_COORD_LATLON;
 329   dest->east_west = (src->x+0.5) * 180 / GZ(17) * socalled_mpp * 2 - 180;
 330   /* We should restore logic of viking:
 331    * tile index on Y axis follow a screen logic (top -> down)
 332    */
 333   dest->north_south = -((src->y+0.5) * 180 / GZ(17) * socalled_mpp * 2 - 90);
 334   g_debug("%s: %d,%d -> %f,%f", __FUNCTION__,
 335           src->x, src->y, dest->east_west, dest->north_south);
 336 }
 337
 338 static gchar *
 339 _get_uri( VikMapSourceDefault *self, MapCoord *src )
 340 {
 341         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);
 342
 343     VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 344         gdouble socalled_mpp;
 345         if (src->scale >= 0)
 346                 socalled_mpp = GZ(src->scale);
 347         else
 348                 socalled_mpp = 1.0/GZ(-src->scale);
 349         /* We should restore logic of viking:
 350      * tile index on Y axis follow a screen logic (top -> down)
 351      */
 352
 353         /* Note : nb tiles on Y axis */
 354         gint nb_tiles = GZ(17 - src->scale - 1);
 355
 356         gchar *uri = g_strdup_printf (priv->url, 17 - src->scale - 1, src->x, nb_tiles - src->y - 1);
 357
 358         return uri;
 359 }
 360
 361 static gchar *
 362 _get_hostname( VikMapSourceDefault *self )
 363 {
 364         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);
 365
 366     VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 367         return g_strdup( priv->hostname );
 368 }
 369
 370 static DownloadMapOptions *
 371 _get_download_options( VikMapSourceDefault *self )
 372 {
 373         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);
 374
 375         VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 376         return &(priv->options);
 377 }
 378
 379 VikTmsMapSource *
 380 vik_tms_map_source_new_with_id (guint8 id, const gchar *label, const gchar *hostname, const gchar *url)
 381 {
 382         return g_object_new(VIK_TYPE_TMS_MAP_SOURCE,
 383                             "id", id, "label", label, "hostname", hostname, "url", url, NULL);
 384 }