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 static gboolean _is_direct_file_access ( VikMapSource *self );
  51
  52 static gchar *_get_uri( VikMapSourceDefault *self, MapCoord *src );
  53 static gchar *_get_hostname( VikMapSourceDefault *self );
  54 static DownloadMapOptions *_get_download_options( VikMapSourceDefault *self );
  55
  56 typedef struct _VikTmsMapSourcePrivate VikTmsMapSourcePrivate;
  57 struct _VikTmsMapSourcePrivate
  58 {
  59   gchar *hostname;
  60   gchar *url;
  61   DownloadMapOptions options;
  62 };
  63
  64 #define VIK_TMS_MAP_SOURCE_PRIVATE(o)  (G_TYPE_INSTANCE_GET_PRIVATE ((o), VIK_TYPE_TMS_MAP_SOURCE, VikTmsMapSourcePrivate))
  65
  66 /* properties */
  67 enum
  68 {
  69   PROP_0,
  70
  71   PROP_HOSTNAME,
  72   PROP_URL,
  73   PROP_REFERER,
  74   PROP_FOLLOW_LOCATION,
  75   PROP_CHECK_FILE_SERVER_TIME,
  76 };
  77
  78 G_DEFINE_TYPE (VikTmsMapSource, vik_tms_map_source, VIK_TYPE_MAP_SOURCE_DEFAULT);
  79
  80 static void
  81 vik_tms_map_source_init (VikTmsMapSource *self)
  82 {
  83   /* initialize the object here */
  84   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
  85
  86   priv->hostname = NULL;
  87   priv->url = NULL;
  88   priv->options.referer = NULL;
  89   priv->options.follow_location = 0;
  90   priv->options.check_file = a_check_map_file;
  91   priv->options.check_file_server_time = FALSE;
  92
  93   g_object_set (G_OBJECT (self),
  94                 "tilesize-x", 256,
  95                 "tilesize-y", 256,
  96                 "drawmode", VIK_VIEWPORT_DRAWMODE_LATLON,
  97                 NULL);
  98 }
  99
 100 static void
 101 vik_tms_map_source_finalize (GObject *object)
 102 {
 103   VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
 104   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
 105
 106   g_free (priv->hostname);
 107   priv->hostname = NULL;
 108   g_free (priv->url);
 109   priv->url = NULL;
 110   g_free (priv->options.referer);
 111   priv->options.referer = NULL;
 112
 113   G_OBJECT_CLASS (vik_tms_map_source_parent_class)->finalize (object);
 114 }
 115
 116 static void
 117 vik_tms_map_source_set_property (GObject      *object,
 118                                     guint         property_id,
 119                                     const GValue *value,
 120                                     GParamSpec   *pspec)
 121 {
 122   VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
 123   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
 124
 125   switch (property_id)
 126     {
 127     case PROP_HOSTNAME:
 128       g_free (priv->hostname);
 129       priv->hostname = g_value_dup_string (value);
 130       break;
 131
 132     case PROP_URL:
 133       g_free (priv->url);
 134       priv->url = g_value_dup_string (value);
 135       break;
 136
 137     case PROP_REFERER:
 138       g_free (priv->options.referer);
 139       priv->options.referer = g_value_dup_string (value);
 140       break;
 141
 142     case PROP_FOLLOW_LOCATION:
 143       priv->options.follow_location = g_value_get_long (value);
 144       break;
 145
 146     case PROP_CHECK_FILE_SERVER_TIME:
 147       priv->options.check_file_server_time = g_value_get_boolean (value);
 148       break;
 149
 150     default:
 151       /* We don't have any other property... */
 152       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
 153       break;
 154     }
 155 }
 156
 157 static void
 158 vik_tms_map_source_get_property (GObject    *object,
 159                                     guint       property_id,
 160                                     GValue     *value,
 161                                     GParamSpec *pspec)
 162 {
 163   VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
 164   VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);
 165
 166   switch (property_id)
 167     {
 168     case PROP_HOSTNAME:
 169       g_value_set_string (value, priv->hostname);
 170       break;
 171
 172     case PROP_URL:
 173       g_value_set_string (value, priv->url);
 174       break;
 175
 176     case PROP_REFERER:
 177       g_value_set_string (value, priv->options.referer);
 178       break;
 179
 180     case PROP_FOLLOW_LOCATION:
 181       g_value_set_long (value, priv->options.follow_location);
 182       break;
 183
 184     case PROP_CHECK_FILE_SERVER_TIME:
 185       g_value_set_boolean (value, priv->options.check_file_server_time);
 186       break;
 187
 188     default:
 189       /* We don't have any other property... */
 190       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
 191       break;
 192     }
 193 }
 194
 195 static void
 196 vik_tms_map_source_class_init (VikTmsMapSourceClass *klass)
 197 {
 198         GObjectClass* object_class = G_OBJECT_CLASS (klass);
 199         VikMapSourceClass* grandparent_class = VIK_MAP_SOURCE_CLASS (klass);
 200         VikMapSourceDefaultClass* parent_class = VIK_MAP_SOURCE_DEFAULT_CLASS (klass);
 201         GParamSpec *pspec = NULL;
 202
 203         object_class->set_property = vik_tms_map_source_set_property;
 204     object_class->get_property = vik_tms_map_source_get_property;
 205
 206         /* Overiding methods */
 207         grandparent_class->coord_to_mapcoord =        _coord_to_mapcoord;
 208         grandparent_class->mapcoord_to_center_coord = _mapcoord_to_center_coord;
 209         grandparent_class->supports_download_only_new = _supports_download_only_new;
 210         grandparent_class->is_direct_file_access = _is_direct_file_access;
 211
 212         parent_class->get_uri = _get_uri;
 213         parent_class->get_hostname = _get_hostname;
 214         parent_class->get_download_options = _get_download_options;
 215
 216         pspec = g_param_spec_string ("hostname",
 217                                      "Hostname",
 218                                      "The hostname of the map server",
 219                                      "<no-set>" /* default value */,
 220                                      G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 221         g_object_class_install_property (object_class, PROP_HOSTNAME, pspec);
 222
 223         pspec = g_param_spec_string ("url",
 224                                      "URL",
 225                                      "The template of the tiles' URL",
 226                                      "<no-set>" /* default value */,
 227                                      G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 228         g_object_class_install_property (object_class, PROP_URL, pspec);
 229
 230         pspec = g_param_spec_string ("referer",
 231                                      "Referer",
 232                                      "The REFERER string to use in HTTP request",
 233                                      NULL /* default value */,
 234                                      G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 235         g_object_class_install_property (object_class, PROP_REFERER, pspec);
 236
 237         pspec = g_param_spec_long ("follow-location",
 238                                    "Follow location",
 239                                "Specifies the number of retries to follow a redirect while downloading a page",
 240                                0  /* minimum value */,
 241                                G_MAXLONG /* maximum value */,
 242                                0  /* default value */,
 243                                G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 244         g_object_class_install_property (object_class, PROP_FOLLOW_LOCATION, pspec);
 245
 246         pspec = g_param_spec_boolean ("check-file-server-time",
 247                                       "Check file server time",
 248                                   "Age of current cache before redownloading tile",
 249                                   FALSE  /* default value */,
 250                                   G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
 251         g_object_class_install_property (object_class, PROP_CHECK_FILE_SERVER_TIME, pspec);
 252
 253         g_type_class_add_private (klass, sizeof (VikTmsMapSourcePrivate));
 254
 255         object_class->finalize = vik_tms_map_source_finalize;
 256 }
 257
 258 /* 1 << (x) is like a 2**(x) */
 259 #define GZ(x) ((1<<(x)))
 260
 261 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),
 262                                            GZ(10), GZ(11), GZ(12), GZ(13), GZ(14), GZ(15), GZ(16), GZ(17) };
 263
 264 static const gint num_scales = (sizeof(scale_mpps) / sizeof(scale_mpps[0]));
 265
 266 static const gdouble scale_neg_mpps[] = { 1.0/GZ(0), 1.0/GZ(1), 1.0/GZ(2), 1.0/GZ(3) };
 267 static const gint num_scales_neg = (sizeof(scale_neg_mpps) / sizeof(scale_neg_mpps[0]));
 268
 269 #define ERROR_MARGIN 0.01
 270 static gint tms_zoom ( gdouble mpp ) {
 271   gint i;
 272   for ( i = 0; i < num_scales; i++ ) {
 273     if ( ABS(scale_mpps[i] - mpp) < ERROR_MARGIN ) {
 274       return i;
 275     }
 276   }
 277   for ( i = 0; i < num_scales_neg; i++ ) {
 278     if ( ABS(scale_neg_mpps[i] - mpp) < 0.000001 ) {
 279       return -i;
 280     }
 281   }
 282
 283   return 255;
 284 }
 285
 286 static gboolean
 287 _is_direct_file_access ( VikMapSource *self )
 288 {
 289         return FALSE;
 290 }
 291
 292 static gboolean
 293 _supports_download_only_new ( VikMapSource *self )
 294 {
 295         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), FALSE);
 296
 297     VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 298
 299         return priv->options.check_file_server_time;
 300 }
 301
 302 static gboolean
 303 _coord_to_mapcoord ( VikMapSource *self, const VikCoord *src, gdouble xzoom, gdouble yzoom, MapCoord *dest )
 304 {
 305   g_assert ( src->mode == VIK_COORD_LATLON );
 306
 307   if ( xzoom != yzoom )
 308     return FALSE;
 309
 310   dest->scale = tms_zoom ( xzoom );
 311   if ( dest->scale == 255 )
 312     return FALSE;
 313
 314   /* Note : GZ(17) / xzoom / 2 = number of tile on Y axis */
 315         g_debug("%s: xzoom=%f yzoom=%f -> %f", __FUNCTION__,
 316           xzoom, yzoom, GZ(17) / xzoom / 2);
 317   dest->x = floor((src->east_west + 180) / 180 * GZ(17) / xzoom / 2);
 318   /* We should restore logic of viking:
 319    * tile index on Y axis follow a screen logic (top -> down)
 320    */
 321   dest->y = floor((180 - (src->north_south + 90)) / 180 * GZ(17) / xzoom / 2);
 322   dest->z = 0;
 323   g_debug("%s: %f,%f -> %d,%d", __FUNCTION__,
 324           src->east_west, src->north_south, dest->x, dest->y);
 325   return TRUE;
 326 }
 327
 328 static void
 329 _mapcoord_to_center_coord ( VikMapSource *self, MapCoord *src, VikCoord *dest )
 330 {
 331   gdouble socalled_mpp;
 332   if (src->scale >= 0)
 333     socalled_mpp = GZ(src->scale);
 334   else
 335     socalled_mpp = 1.0/GZ(-src->scale);
 336   dest->mode = VIK_COORD_LATLON;
 337   dest->east_west = (src->x+0.5) * 180 / GZ(17) * socalled_mpp * 2 - 180;
 338   /* We should restore logic of viking:
 339    * tile index on Y axis follow a screen logic (top -> down)
 340    */
 341   dest->north_south = -((src->y+0.5) * 180 / GZ(17) * socalled_mpp * 2 - 90);
 342   g_debug("%s: %d,%d -> %f,%f", __FUNCTION__,
 343           src->x, src->y, dest->east_west, dest->north_south);
 344 }
 345
 346 static gchar *
 347 _get_uri( VikMapSourceDefault *self, MapCoord *src )
 348 {
 349         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);
 350
 351     VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 352         /* We should restore logic of viking:
 353      * tile index on Y axis follow a screen logic (top -> down)
 354      */
 355
 356         /* Note : nb tiles on Y axis */
 357         gint nb_tiles = GZ(17 - src->scale - 1);
 358
 359         gchar *uri = g_strdup_printf (priv->url, 17 - src->scale - 1, src->x, nb_tiles - src->y - 1);
 360
 361         return uri;
 362 }
 363
 364 static gchar *
 365 _get_hostname( VikMapSourceDefault *self )
 366 {
 367         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);
 368
 369     VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 370         return g_strdup( priv->hostname );
 371 }
 372
 373 static DownloadMapOptions *
 374 _get_download_options( VikMapSourceDefault *self )
 375 {
 376         g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);
 377
 378         VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
 379         return &(priv->options);
 380 }
 381
 382 VikTmsMapSource *
 383 vik_tms_map_source_new_with_id (guint8 id, const gchar *label, const gchar *hostname, const gchar *url)
 384 {
 385         return g_object_new(VIK_TYPE_TMS_MAP_SOURCE,
 386                             "id", id, "label", label, "hostname", hostname, "url", url, NULL);
 387 }