src/viktmsmapsource.c

/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
/*
 * viking
 * Copyright (C) 2010, Guilhem Bonnefille <guilhem.bonnefille@gmail.com>
 *
 * viking is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * viking is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

 /**
  * SECTION:viktmsmapsource
  * @short_description: the class for TMS oriented map sources
  *
  * The #VikTmsMapSource class handles TMS oriented map sources.
  *
  * The tiles are in 'equirectangular'.
  * http://en.wikipedia.org/wiki/Equirectangular_projection
  *
  * Such service is also a type of TMS (Tile Map Service) as defined in
  * OSGeo's wiki.
  * http://wiki.osgeo.org/wiki/Tile_Map_Service_Specification
  * Following this specification, the protocol handled by this class
  * follows the global-geodetic profile.
  */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef HAVE_MATH_H
#include <math.h>
#endif

#include "globals.h"
#include "viktmsmapsource.h"

static gboolean _coord_to_mapcoord ( VikMapSource *self, const VikCoord *src, gdouble xzoom, gdouble yzoom, MapCoord *dest );
static void _mapcoord_to_center_coord ( VikMapSource *self, MapCoord *src, VikCoord *dest );
static gboolean _supports_download_only_new (VikMapSource *self );

static gchar *_get_uri( VikMapSourceDefault *self, MapCoord *src );
static gchar *_get_hostname( VikMapSourceDefault *self );
static DownloadMapOptions *_get_download_options( VikMapSourceDefault *self );

typedef struct _VikTmsMapSourcePrivate VikTmsMapSourcePrivate;
struct _VikTmsMapSourcePrivate
{
  gchar *hostname;
  gchar *url;
  DownloadMapOptions options;
};

#define VIK_TMS_MAP_SOURCE_PRIVATE(o)  (G_TYPE_INSTANCE_GET_PRIVATE ((o), VIK_TYPE_TMS_MAP_SOURCE, VikTmsMapSourcePrivate))

/* properties */
enum
{
  PROP_0,

  PROP_HOSTNAME,
  PROP_URL,
  PROP_REFERER,
  PROP_FOLLOW_LOCATION,
  PROP_CHECK_FILE_SERVER_TIME,
};

G_DEFINE_TYPE (VikTmsMapSource, vik_tms_map_source, VIK_TYPE_MAP_SOURCE_DEFAULT);

static void
vik_tms_map_source_init (VikTmsMapSource *self)
{
  /* initialize the object here */
  VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);

  priv->hostname = NULL;
  priv->url = NULL;
  priv->options.referer = NULL;
  priv->options.follow_location = 0;
  priv->options.check_file = a_check_map_file;
  priv->options.check_file_server_time = FALSE;

  g_object_set (G_OBJECT (self),
                "tilesize-x", 256,
                "tilesize-y", 256,
                "drawmode", VIK_VIEWPORT_DRAWMODE_LATLON,
                NULL);
}

static void
vik_tms_map_source_finalize (GObject *object)
{
  VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
  VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);

  g_free (priv->hostname);
  priv->hostname = NULL;
  g_free (priv->url);
  priv->url = NULL;
  g_free (priv->options.referer);
  priv->options.referer = NULL;

  G_OBJECT_CLASS (vik_tms_map_source_parent_class)->finalize (object);
}

static void
vik_tms_map_source_set_property (GObject      *object,
                                    guint         property_id,
                                    const GValue *value,
                                    GParamSpec   *pspec)
{
  VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
  VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);

  switch (property_id)
    {
    case PROP_HOSTNAME:
      g_free (priv->hostname);
      priv->hostname = g_value_dup_string (value);
      break;

    case PROP_URL:
      g_free (priv->url);
      priv->url = g_value_dup_string (value);
      break;

    case PROP_REFERER:
      g_free (priv->options.referer);
      priv->options.referer = g_value_dup_string (value);
      break;

    case PROP_FOLLOW_LOCATION:
      priv->options.follow_location = g_value_get_long (value);
      break;

    case PROP_CHECK_FILE_SERVER_TIME:
      priv->options.check_file_server_time = g_value_get_boolean (value);
      break;

    default:
      /* We don't have any other property... */
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
    }
}

static void
vik_tms_map_source_get_property (GObject    *object,
                                    guint       property_id,
                                    GValue     *value,
                                    GParamSpec *pspec)
{
  VikTmsMapSource *self = VIK_TMS_MAP_SOURCE (object);
  VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE (self);

  switch (property_id)
    {
    case PROP_HOSTNAME:
      g_value_set_string (value, priv->hostname);
      break;

    case PROP_URL:
      g_value_set_string (value, priv->url);
      break;

    case PROP_REFERER:
      g_value_set_string (value, priv->options.referer);
      break;

    case PROP_FOLLOW_LOCATION:
      g_value_set_long (value, priv->options.follow_location);
      break;

    case PROP_CHECK_FILE_SERVER_TIME:
      g_value_set_boolean (value, priv->options.check_file_server_time);
      break;

    default:
      /* We don't have any other property... */
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
    }
}

static void
vik_tms_map_source_class_init (VikTmsMapSourceClass *klass)
{
	GObjectClass* object_class = G_OBJECT_CLASS (klass);
	VikMapSourceClass* grandparent_class = VIK_MAP_SOURCE_CLASS (klass);
	VikMapSourceDefaultClass* parent_class = VIK_MAP_SOURCE_DEFAULT_CLASS (klass);
	GParamSpec *pspec = NULL;

	object_class->set_property = vik_tms_map_source_set_property;
    object_class->get_property = vik_tms_map_source_get_property;

	/* Overiding methods */
	grandparent_class->coord_to_mapcoord =        _coord_to_mapcoord;
	grandparent_class->mapcoord_to_center_coord = _mapcoord_to_center_coord;
	grandparent_class->supports_download_only_new = _supports_download_only_new;

	parent_class->get_uri = _get_uri;
	parent_class->get_hostname = _get_hostname;
	parent_class->get_download_options = _get_download_options;

	pspec = g_param_spec_string ("hostname",
	                             "Hostname",
	                             "The hostname of the map server",
	                             "<no-set>" /* default value */,
	                             G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_HOSTNAME, pspec);

	pspec = g_param_spec_string ("url",
	                             "URL",
	                             "The template of the tiles' URL",
	                             "<no-set>" /* default value */,
	                             G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_URL, pspec);

	pspec = g_param_spec_string ("referer",
	                             "Referer",
	                             "The REFERER string to use in HTTP request",
	                             NULL /* default value */,
	                             G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_REFERER, pspec);

	pspec = g_param_spec_long ("follow-location",
	                           "Follow location",
                               "Specifies the number of retries to follow a redirect while downloading a page",
                               0  /* minimum value */,
                               G_MAXLONG /* maximum value */,
                               0  /* default value */,
                               G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_FOLLOW_LOCATION, pspec);

	pspec = g_param_spec_boolean ("check-file-server-time",
	                              "Check file server time",
                                  "Age of current cache before redownloading tile",
                                  FALSE  /* default value */,
                                  G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_CHECK_FILE_SERVER_TIME, pspec);

	g_type_class_add_private (klass, sizeof (VikTmsMapSourcePrivate));

	object_class->finalize = vik_tms_map_source_finalize;
}

/* 1 << (x) is like a 2**(x) */
#define GZ(x) ((1<<(x)))

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),
                                           GZ(10), GZ(11), GZ(12), GZ(13), GZ(14), GZ(15), GZ(16), GZ(17) };

static const gint num_scales = (sizeof(scale_mpps) / sizeof(scale_mpps[0]));

static const gdouble scale_neg_mpps[] = { 1.0/GZ(0), 1.0/GZ(1), 1.0/GZ(2), 1.0/GZ(3) };
static const gint num_scales_neg = (sizeof(scale_neg_mpps) / sizeof(scale_neg_mpps[0]));

#define ERROR_MARGIN 0.01
static gint tms_zoom ( gdouble mpp ) {
  gint i;
  for ( i = 0; i < num_scales; i++ ) {
    if ( ABS(scale_mpps[i] - mpp) < ERROR_MARGIN ) {
      return i;
    }
  }
  for ( i = 0; i < num_scales_neg; i++ ) {
    if ( ABS(scale_neg_mpps[i] - mpp) < 0.000001 ) {
      return -i;
    }
  }

  return 255;
}

gboolean
_supports_download_only_new (VikMapSource *self)
{
	g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), FALSE);

    VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);

	return priv->options.check_file_server_time;
}

static gboolean
_coord_to_mapcoord ( VikMapSource *self, const VikCoord *src, gdouble xzoom, gdouble yzoom, MapCoord *dest )
{
  g_assert ( src->mode == VIK_COORD_LATLON );

  if ( xzoom != yzoom )
    return FALSE;

  dest->scale = tms_zoom ( xzoom );
  if ( dest->scale == 255 )
    return FALSE;

  /* Note : GZ(17) / xzoom / 2 = number of tile on Y axis */
	g_debug("%s: xzoom=%f yzoom=%f -> %f", __FUNCTION__,
          xzoom, yzoom, GZ(17) / xzoom / 2);
  dest->x = floor((src->east_west + 180) / 180 * GZ(17) / xzoom / 2);
  /* We should restore logic of viking:
   * tile index on Y axis follow a screen logic (top -> down)
   */
  dest->y = floor((180 - (src->north_south + 90)) / 180 * GZ(17) / xzoom / 2);
  dest->z = 0;
  g_debug("%s: %f,%f -> %d,%d", __FUNCTION__,
          src->east_west, src->north_south, dest->x, dest->y);
  return TRUE;
}

static void
_mapcoord_to_center_coord ( VikMapSource *self, MapCoord *src, VikCoord *dest )
{
  gdouble socalled_mpp;
  if (src->scale >= 0)
    socalled_mpp = GZ(src->scale);
  else
    socalled_mpp = 1.0/GZ(-src->scale);
  dest->mode = VIK_COORD_LATLON;
  dest->east_west = (src->x+0.5) * 180 / GZ(17) * socalled_mpp * 2 - 180;
  /* We should restore logic of viking:
   * tile index on Y axis follow a screen logic (top -> down)
   */
  dest->north_south = -((src->y+0.5) * 180 / GZ(17) * socalled_mpp * 2 - 90);
  g_debug("%s: %d,%d -> %f,%f", __FUNCTION__,
          src->x, src->y, dest->east_west, dest->north_south);
}

static gchar *
_get_uri( VikMapSourceDefault *self, MapCoord *src )
{
	g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);

    VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
	gdouble socalled_mpp;
	if (src->scale >= 0)
		socalled_mpp = GZ(src->scale);
	else
		socalled_mpp = 1.0/GZ(-src->scale);
	/* We should restore logic of viking:
     * tile index on Y axis follow a screen logic (top -> down)
     */

	/* Note : nb tiles on Y axis */
	gint nb_tiles = GZ(17 - src->scale - 1);

	gchar *uri = g_strdup_printf (priv->url, 17 - src->scale - 1, src->x, nb_tiles - src->y - 1);

	return uri;
}

static gchar *
_get_hostname( VikMapSourceDefault *self )
{
	g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);

    VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
	return g_strdup( priv->hostname );
}

static DownloadMapOptions *
_get_download_options( VikMapSourceDefault *self )
{
	g_return_val_if_fail (VIK_IS_TMS_MAP_SOURCE(self), NULL);

	VikTmsMapSourcePrivate *priv = VIK_TMS_MAP_SOURCE_PRIVATE(self);
	return &(priv->options);
}

VikTmsMapSource *
vik_tms_map_source_new_with_id (guint8 id, const gchar *label, const gchar *hostname, const gchar *url)
{
	return g_object_new(VIK_TYPE_TMS_MAP_SOURCE,
	                    "id", id, "label", label, "hostname", hostname, "url", url, NULL);
}
Commit	Line	Data
	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	}