src/vikslippymapsource.c

/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
/*
 * viking
 * Copyright (C) Guilhem Bonnefille 2009 <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/>.
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

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

#include "globals.h"
#include "vikslippymapsource.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 int _download ( VikMapSource *self, MapCoord *src, const gchar *dest_fn, void *handle );
static void * _download_handle_init ( VikMapSource *self);
static void _download_handle_cleanup ( VikMapSource *self, void *handle);
static gboolean _supports_if_modified_since (VikMapSource *self );

static gchar *_get_uri( VikSlippyMapSource *self, MapCoord *src );
static gchar *_get_hostname( VikSlippyMapSource *self );
static DownloadOptions *_get_download_options( VikSlippyMapSource *self );

typedef struct _VikSlippyMapSourcePrivate VikSlippyMapSourcePrivate;
struct _VikSlippyMapSourcePrivate
{
  gchar *hostname;
  gchar *url;
  DownloadOptions options;
};

#define VIK_SLIPPY_MAP_SOURCE_PRIVATE(o)  (G_TYPE_INSTANCE_GET_PRIVATE ((o), VIK_TYPE_SLIPPY_MAP_SOURCE, VikSlippyMapSourcePrivate))

/* properties */
enum
{
  PROP_0,

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

G_DEFINE_TYPE_EXTENDED (VikSlippyMapSource, vik_slippy_map_source, VIK_TYPE_MAP_SOURCE_DEFAULT, (GTypeFlags)0,);

static void
vik_slippy_map_source_init (VikSlippyMapSource *self)
{
  /* initialize the object here */
  VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_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_MERCATOR,
                NULL);
}

static void
vik_slippy_map_source_finalize (GObject *object)
{
  VikSlippyMapSource *self = VIK_SLIPPY_MAP_SOURCE (object);
  VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_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_slippy_map_source_parent_class)->finalize (object);
}

static void
vik_slippy_map_source_set_property (GObject      *object,
                                    guint         property_id,
                                    const GValue *value,
                                    GParamSpec   *pspec)
{
  VikSlippyMapSource *self = VIK_SLIPPY_MAP_SOURCE (object);
  VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_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_slippy_map_source_get_property (GObject    *object,
                                    guint       property_id,
                                    GValue     *value,
                                    GParamSpec *pspec)
{
  VikSlippyMapSource *self = VIK_SLIPPY_MAP_SOURCE (object);
  VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_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_slippy_map_source_class_init (VikSlippyMapSourceClass *klass)
{
	GObjectClass* object_class = G_OBJECT_CLASS (klass);
	VikMapSourceClass* parent_class = VIK_MAP_SOURCE_CLASS (klass);
	GParamSpec *pspec = NULL;

	object_class->set_property = vik_slippy_map_source_set_property;
    object_class->get_property = vik_slippy_map_source_get_property;

	/* Overiding methods */
	parent_class->coord_to_mapcoord =        _coord_to_mapcoord;
	parent_class->mapcoord_to_center_coord = _mapcoord_to_center_coord;
	parent_class->download =                 _download;
	parent_class->download_handle_init =     _download_handle_init;
	parent_class->download_handle_cleanup =  _download_handle_cleanup;
	parent_class->supports_if_modified_since = _supports_if_modified_since;

	/* Default implementation of methods */
	klass->get_uri = _get_uri;
	klass->get_hostname = _get_hostname;
	klass->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 (VikSlippyMapSourcePrivate));

	object_class->finalize = vik_slippy_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]));

#define ERROR_MARGIN 0.01
static guint8 slippy_zoom ( gdouble mpp ) {
  gint i;
  for ( i = 0; i < num_scales; i++ ) {
    if ( ABS(scale_mpps[i] - mpp) < ERROR_MARGIN )
      return i;
  }
  return 255;
}

gchar *
vik_slippy_map_source_get_uri( VikSlippyMapSource *self, MapCoord *src )
{
	VikSlippyMapSourceClass *klass;
	g_return_val_if_fail (self != NULL, 0);
	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE (self), 0);
	klass = VIK_SLIPPY_MAP_SOURCE_GET_CLASS(self);

	g_return_val_if_fail (klass->get_uri != NULL, 0);

	return (*klass->get_uri)(self, src);
}

gchar *
vik_slippy_map_source_get_hostname( VikSlippyMapSource *self )
{
	VikSlippyMapSourceClass *klass;
	g_return_val_if_fail (self != NULL, 0);
	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE (self), 0);
	klass = VIK_SLIPPY_MAP_SOURCE_GET_CLASS(self);

	g_return_val_if_fail (klass->get_hostname != NULL, 0);

	return (*klass->get_hostname)(self);
}

DownloadOptions *
vik_slippy_map_source_get_download_options( VikSlippyMapSource *self )
{
	VikSlippyMapSourceClass *klass;
	g_return_val_if_fail (self != NULL, 0);
	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE (self), 0);
	klass = VIK_SLIPPY_MAP_SOURCE_GET_CLASS(self);

	g_return_val_if_fail (klass->get_download_options != NULL, 0);

	return (*klass->get_download_options)(self);
}

gboolean
_supports_if_modified_since (VikMapSource *self)
{
	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), FALSE);

    VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_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 = slippy_zoom ( xzoom );
  if ( dest->scale == 255 )
    return FALSE;

  dest->x = (src->east_west + 180) / 360 * GZ(17) / xzoom;
  dest->y = (180 - MERCLAT(src->north_south)) / 360 * GZ(17) / xzoom;
  dest->z = 0;

  return TRUE;
}

static void
_mapcoord_to_center_coord ( VikMapSource *self, MapCoord *src, VikCoord *dest )
{
  gdouble socalled_mpp = GZ(src->scale);
  dest->mode = VIK_COORD_LATLON;
  dest->east_west = ((src->x+0.5) / GZ(17) * socalled_mpp * 360) - 180;
  dest->north_south = DEMERCLAT(180 - ((src->y+0.5) / GZ(17) * socalled_mpp * 360));
}

static int
_download ( VikMapSource *self, MapCoord *src, const gchar *dest_fn, void *handle )
{
   int res;
   gchar *uri = vik_slippy_map_source_get_uri(VIK_SLIPPY_MAP_SOURCE(self), src);
   gchar *host = vik_slippy_map_source_get_hostname(VIK_SLIPPY_MAP_SOURCE(self));
   DownloadOptions *options = vik_slippy_map_source_get_download_options(VIK_SLIPPY_MAP_SOURCE(self));
   res = a_http_download_get_url ( host, uri, dest_fn, options, handle );
   g_free ( uri );
   g_free ( host );
   return res;
}

static void *
_download_handle_init ( VikMapSource *self )
{
   return a_download_handle_init ();
}


static void
_download_handle_cleanup ( VikMapSource *self, void *handle )
{
   return a_download_handle_cleanup ( handle );
}

static gchar *
_get_uri( VikSlippyMapSource *self, MapCoord *src )
{
	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), NULL);

    VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE(self);
	gchar *uri = g_strdup_printf (priv->url, 17 - src->scale, src->x, src->y);
	return uri;
}

static gchar *
_get_hostname( VikSlippyMapSource *self )
{
	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), NULL);

    VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE(self);
	return g_strdup( priv->hostname );
}

static DownloadOptions *
_get_download_options( VikSlippyMapSource *self )
{
	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), NULL);

	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE(self);
	return &(priv->options);
}

VikSlippyMapSource *
vik_slippy_map_source_new_with_id (guint8 id, const gchar *label, const gchar *hostname, const gchar *url)
{
	return g_object_new(VIK_TYPE_SLIPPY_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) Guilhem Bonnefille 2009 <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	#ifdef HAVE_CONFIG_H
	20	#include "config.h"
	21	#endif
	22
	23	#ifdef HAVE_MATH_H
	24	#include <math.h>
	25	#endif
	26
	27	#include "globals.h"
	28	#include "vikslippymapsource.h"
	29
	30	static gboolean _coord_to_mapcoord ( VikMapSource self, const VikCoord src, gdouble xzoom, gdouble yzoom, MapCoord *dest );
	31	static void _mapcoord_to_center_coord ( VikMapSource self, MapCoord src, VikCoord *dest );
	32	static int _download ( VikMapSource self, MapCoord src, const gchar dest_fn, void handle );
	33	static void * _download_handle_init ( VikMapSource *self);
	34	static void _download_handle_cleanup ( VikMapSource self, void handle);
	35	static gboolean _supports_if_modified_since (VikMapSource *self );
	36
	37	static gchar _get_uri( VikSlippyMapSource self, MapCoord *src );
	38	static gchar _get_hostname( VikSlippyMapSource self );
	39	static DownloadOptions _get_download_options( VikSlippyMapSource self );
	40
	41	typedef struct _VikSlippyMapSourcePrivate VikSlippyMapSourcePrivate;
	42	struct _VikSlippyMapSourcePrivate
	43	{
	44	gchar *hostname;
	45	gchar *url;
	46	DownloadOptions options;
	47	};
	48
	49	#define VIK_SLIPPY_MAP_SOURCE_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), VIK_TYPE_SLIPPY_MAP_SOURCE, VikSlippyMapSourcePrivate))
	50
	51	/* properties */
	52	enum
	53	{
	54	PROP_0,
	55
	56	PROP_HOSTNAME,
	57	PROP_URL,
	58	PROP_REFERER,
	59	PROP_FOLLOW_LOCATION,
	60	PROP_CHECK_FILE_SERVER_TIME,
	61	};
	62
	63	G_DEFINE_TYPE_EXTENDED (VikSlippyMapSource, vik_slippy_map_source, VIK_TYPE_MAP_SOURCE_DEFAULT, (GTypeFlags)0,);
	64
	65	static void
	66	vik_slippy_map_source_init (VikSlippyMapSource *self)
	67	{
	68	/* initialize the object here */
	69	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE (self);
	70
	71	priv->hostname = NULL;
	72	priv->url = NULL;
	73	priv->options.referer = NULL;
	74	priv->options.follow_location = 0;
	75	priv->options.check_file = a_check_map_file;
	76	priv->options.check_file_server_time = FALSE;
	77
	78	g_object_set (G_OBJECT (self),
	79	"tilesize-x", 256,
	80	"tilesize-y", 256,
	81	"drawmode", VIK_VIEWPORT_DRAWMODE_MERCATOR,
	82	NULL);
	83	}
	84
	85	static void
	86	vik_slippy_map_source_finalize (GObject *object)
	87	{
	88	VikSlippyMapSource *self = VIK_SLIPPY_MAP_SOURCE (object);
	89	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE (self);
	90
	91	g_free (priv->hostname);
	92	priv->hostname = NULL;
	93	g_free (priv->url);
	94	priv->url = NULL;
	95	g_free (priv->options.referer);
	96	priv->options.referer = NULL;
	97
	98	G_OBJECT_CLASS (vik_slippy_map_source_parent_class)->finalize (object);
	99	}
	100
	101	static void
	102	vik_slippy_map_source_set_property (GObject *object,
	103	guint property_id,
	104	const GValue *value,
	105	GParamSpec *pspec)
	106	{
	107	VikSlippyMapSource *self = VIK_SLIPPY_MAP_SOURCE (object);
	108	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE (self);
	109
	110	switch (property_id)
	111	{
	112	case PROP_HOSTNAME:
	113	g_free (priv->hostname);
	114	priv->hostname = g_value_dup_string (value);
	115	break;
	116
	117	case PROP_URL:
	118	g_free (priv->url);
	119	priv->url = g_value_dup_string (value);
	120	break;
	121
	122	case PROP_REFERER:
	123	g_free (priv->options.referer);
	124	priv->options.referer = g_value_dup_string (value);
	125	break;
	126
	127	case PROP_FOLLOW_LOCATION:
	128	priv->options.follow_location = g_value_get_long (value);
	129	break;
	130
	131	case PROP_CHECK_FILE_SERVER_TIME:
	132	priv->options.check_file_server_time = g_value_get_boolean (value);
	133	break;
	134
	135	default:
	136	/* We don't have any other property... */
	137	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
	138	break;
	139	}
	140	}
	141
	142	static void
	143	vik_slippy_map_source_get_property (GObject *object,
	144	guint property_id,
	145	GValue *value,
	146	GParamSpec *pspec)
	147	{
	148	VikSlippyMapSource *self = VIK_SLIPPY_MAP_SOURCE (object);
	149	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE (self);
	150
	151	switch (property_id)
	152	{
	153	case PROP_HOSTNAME:
	154	g_value_set_string (value, priv->hostname);
	155	break;
	156
	157	case PROP_URL:
	158	g_value_set_string (value, priv->url);
	159	break;
	160
	161	case PROP_REFERER:
	162	g_value_set_string (value, priv->options.referer);
	163	break;
	164
	165	case PROP_FOLLOW_LOCATION:
	166	g_value_set_long (value, priv->options.follow_location);
	167	break;
	168
	169	case PROP_CHECK_FILE_SERVER_TIME:
	170	g_value_set_boolean (value, priv->options.check_file_server_time);
	171	break;
	172
	173	default:
	174	/* We don't have any other property... */
	175	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
	176	break;
	177	}
	178	}
	179
	180	static void
	181	vik_slippy_map_source_class_init (VikSlippyMapSourceClass *klass)
	182	{
	183	GObjectClass* object_class = G_OBJECT_CLASS (klass);
	184	VikMapSourceClass* parent_class = VIK_MAP_SOURCE_CLASS (klass);
	185	GParamSpec *pspec = NULL;
	186
	187	object_class->set_property = vik_slippy_map_source_set_property;
	188	object_class->get_property = vik_slippy_map_source_get_property;
	189
	190	/* Overiding methods */
	191	parent_class->coord_to_mapcoord = _coord_to_mapcoord;
	192	parent_class->mapcoord_to_center_coord = _mapcoord_to_center_coord;
	193	parent_class->download = _download;
	194	parent_class->download_handle_init = _download_handle_init;
	195	parent_class->download_handle_cleanup = _download_handle_cleanup;
	196	parent_class->supports_if_modified_since = _supports_if_modified_since;
	197
	198	/* Default implementation of methods */
	199	klass->get_uri = _get_uri;
	200	klass->get_hostname = _get_hostname;
	201	klass->get_download_options = _get_download_options;
	202
	203	pspec = g_param_spec_string ("hostname",
	204	"Hostname",
	205	"The hostname of the map server",
	206	"<no-set>" /* default value */,
	207	G_PARAM_CONSTRUCT_ONLY \| G_PARAM_READWRITE);
	208	g_object_class_install_property (object_class, PROP_HOSTNAME, pspec);
	209
	210	pspec = g_param_spec_string ("url",
	211	"URL",
	212	"The template of the tiles' URL",
	213	"<no-set>" /* default value */,
	214	G_PARAM_CONSTRUCT_ONLY \| G_PARAM_READWRITE);
	215	g_object_class_install_property (object_class, PROP_URL, pspec);
	216
	217	pspec = g_param_spec_string ("referer",
	218	"Referer",
	219	"The REFERER string to use in HTTP request",
	220	NULL /* default value */,
	221	G_PARAM_CONSTRUCT_ONLY \| G_PARAM_READWRITE);
	222	g_object_class_install_property (object_class, PROP_REFERER, pspec);
	223
	224	pspec = g_param_spec_long ("follow-location",
	225	"Follow location",
	226	"Specifies the number of retries to follow a redirect while downloading a page",
	227	0 /* minimum value */,
	228	G_MAXLONG /* maximum value */,
	229	0 /* default value */,
	230	G_PARAM_CONSTRUCT_ONLY \| G_PARAM_READWRITE);
	231	g_object_class_install_property (object_class, PROP_FOLLOW_LOCATION, pspec);
	232
	233	pspec = g_param_spec_boolean ("check-file-server-time",
	234	"Check file server time",
	235	"Age of current cache before redownloading tile",
	236	FALSE /* default value */,
	237	G_PARAM_CONSTRUCT_ONLY \| G_PARAM_READWRITE);
	238	g_object_class_install_property (object_class, PROP_CHECK_FILE_SERVER_TIME, pspec);
	239
	240	g_type_class_add_private (klass, sizeof (VikSlippyMapSourcePrivate));
	241
	242	object_class->finalize = vik_slippy_map_source_finalize;
	243	}
	244
	245	/* 1 << (x) is like a 2*(x) /
	246	#define GZ(x) ((1<<x))
	247
	248	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),
	249	GZ(10), GZ(11), GZ(12), GZ(13), GZ(14), GZ(15), GZ(16), GZ(17) };
	250
	251	static const gint num_scales = (sizeof(scale_mpps) / sizeof(scale_mpps[0]));
	252
	253	#define ERROR_MARGIN 0.01
	254	static guint8 slippy_zoom ( gdouble mpp ) {
	255	gint i;
	256	for ( i = 0; i < num_scales; i++ ) {
	257	if ( ABS(scale_mpps[i] - mpp) < ERROR_MARGIN )
	258	return i;
	259	}
	260	return 255;
	261	}
	262
	263	gchar *
	264	vik_slippy_map_source_get_uri( VikSlippyMapSource self, MapCoord src )
	265	{
	266	VikSlippyMapSourceClass *klass;
	267	g_return_val_if_fail (self != NULL, 0);
	268	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE (self), 0);
	269	klass = VIK_SLIPPY_MAP_SOURCE_GET_CLASS(self);
	270
	271	g_return_val_if_fail (klass->get_uri != NULL, 0);
	272
	273	return (*klass->get_uri)(self, src);
	274	}
	275
	276	gchar *
	277	vik_slippy_map_source_get_hostname( VikSlippyMapSource *self )
	278	{
	279	VikSlippyMapSourceClass *klass;
	280	g_return_val_if_fail (self != NULL, 0);
	281	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE (self), 0);
	282	klass = VIK_SLIPPY_MAP_SOURCE_GET_CLASS(self);
	283
	284	g_return_val_if_fail (klass->get_hostname != NULL, 0);
	285
	286	return (*klass->get_hostname)(self);
	287	}
	288
	289	DownloadOptions *
	290	vik_slippy_map_source_get_download_options( VikSlippyMapSource *self )
	291	{
	292	VikSlippyMapSourceClass *klass;
	293	g_return_val_if_fail (self != NULL, 0);
	294	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE (self), 0);
	295	klass = VIK_SLIPPY_MAP_SOURCE_GET_CLASS(self);
	296
	297	g_return_val_if_fail (klass->get_download_options != NULL, 0);
	298
	299	return (*klass->get_download_options)(self);
	300	}
	301
	302	gboolean
	303	_supports_if_modified_since (VikMapSource *self)
	304	{
	305	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), FALSE);
	306
	307	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE(self);
	308
	309	return priv->options.check_file_server_time;
	310	}
	311	static gboolean
	312	_coord_to_mapcoord ( VikMapSource self, const VikCoord src, gdouble xzoom, gdouble yzoom, MapCoord *dest )
	313	{
	314	g_assert ( src->mode == VIK_COORD_LATLON );
	315
	316	if ( xzoom != yzoom )
	317	return FALSE;
	318
	319	dest->scale = slippy_zoom ( xzoom );
	320	if ( dest->scale == 255 )
	321	return FALSE;
	322
	323	dest->x = (src->east_west + 180) / 360 * GZ(17) / xzoom;
	324	dest->y = (180 - MERCLAT(src->north_south)) / 360 * GZ(17) / xzoom;
	325	dest->z = 0;
	326
	327	return TRUE;
	328	}
	329
	330	static void
	331	_mapcoord_to_center_coord ( VikMapSource self, MapCoord src, VikCoord *dest )
	332	{
	333	gdouble socalled_mpp = GZ(src->scale);
	334	dest->mode = VIK_COORD_LATLON;
	335	dest->east_west = ((src->x+0.5) / GZ(17) * socalled_mpp * 360) - 180;
	336	dest->north_south = DEMERCLAT(180 - ((src->y+0.5) / GZ(17) * socalled_mpp * 360));
	337	}
	338
	339	static int
	340	_download ( VikMapSource self, MapCoord src, const gchar dest_fn, void handle )
	341	{
	342	int res;
	343	gchar *uri = vik_slippy_map_source_get_uri(VIK_SLIPPY_MAP_SOURCE(self), src);
	344	gchar *host = vik_slippy_map_source_get_hostname(VIK_SLIPPY_MAP_SOURCE(self));
	345	DownloadOptions *options = vik_slippy_map_source_get_download_options(VIK_SLIPPY_MAP_SOURCE(self));
	346	res = a_http_download_get_url ( host, uri, dest_fn, options, handle );
	347	g_free ( uri );
	348	g_free ( host );
	349	return res;
	350	}
	351
	352	static void *
	353	_download_handle_init ( VikMapSource *self )
	354	{
	355	return a_download_handle_init ();
	356	}
	357
	358
	359	static void
	360	_download_handle_cleanup ( VikMapSource self, void handle )
	361	{
	362	return a_download_handle_cleanup ( handle );
	363	}
	364
	365	static gchar *
	366	_get_uri( VikSlippyMapSource self, MapCoord src )
	367	{
	368	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), NULL);
	369
	370	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE(self);
	371	gchar *uri = g_strdup_printf (priv->url, 17 - src->scale, src->x, src->y);
	372	return uri;
	373	}
	374
	375	static gchar *
	376	_get_hostname( VikSlippyMapSource *self )
	377	{
	378	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), NULL);
	379
	380	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE(self);
	381	return g_strdup( priv->hostname );
	382	}
	383
	384	static DownloadOptions *
	385	_get_download_options( VikSlippyMapSource *self )
	386	{
	387	g_return_val_if_fail (VIK_IS_SLIPPY_MAP_SOURCE(self), NULL);
	388
	389	VikSlippyMapSourcePrivate *priv = VIK_SLIPPY_MAP_SOURCE_PRIVATE(self);
	390	return &(priv->options);
	391	}
	392
	393	VikSlippyMapSource *
	394	vik_slippy_map_source_new_with_id (guint8 id, const gchar label, const gchar hostname, const gchar *url)
	395	{
	396	return g_object_new(VIK_TYPE_SLIPPY_MAP_SOURCE,
	397	"id", id, "label", label, "hostname", hostname, "url", url, NULL);
	398	}