2 * viking -- GPS Data and Topo Analyzer, Explorer, and Manager
4 * Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.net>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
31 #include "curl_download.h"
34 #include "vikmapslayer.h"
37 static int google_download ( MapCoord *src, const gchar *dest_fn );
38 static int google_trans_download ( MapCoord *src, const gchar *dest_fn );
39 static int google_kh_download ( MapCoord *src, const gchar *dest_fn );
40 static void google_mapcoord_to_center_coord ( MapCoord *src, VikCoord *dest );
41 static gboolean google_coord_to_mapcoord ( const VikCoord *src, gdouble xzoom, gdouble yzoom, MapCoord *dest );
43 static DownloadOptions google_options = { "http://maps.google.com/", 0 };
46 VikMapsLayer_MapType google_1 = { 7, 256, 256, VIK_VIEWPORT_DRAWMODE_MERCATOR, google_coord_to_mapcoord, google_mapcoord_to_center_coord, google_download };
47 VikMapsLayer_MapType google_2 = { 10, 256, 256, VIK_VIEWPORT_DRAWMODE_MERCATOR, google_coord_to_mapcoord, google_mapcoord_to_center_coord, google_trans_download };
48 VikMapsLayer_MapType google_3 = { 11, 256, 256, VIK_VIEWPORT_DRAWMODE_MERCATOR, google_coord_to_mapcoord, google_mapcoord_to_center_coord, google_kh_download };
50 maps_layer_register_type("Google Maps", 7, &google_1);
51 maps_layer_register_type("Transparent Google Maps", 10, &google_2);
52 maps_layer_register_type("Google Satellite Images", 11, &google_3);
55 /* 1 << (x) is like a 2**(x) */
56 #define GZ(x) ((1<<x))
58 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),
59 GZ(10), GZ(11), GZ(12), GZ(13), GZ(14), GZ(15), GZ(16), GZ(17) };
61 static const gint num_scales = (sizeof(scale_mpps) / sizeof(scale_mpps[0]));
63 #define ERROR_MARGIN 0.01
64 guint8 google_zoom ( gdouble mpp ) {
66 for ( i = 0; i < num_scales; i++ ) {
67 if ( ABS(scale_mpps[i] - mpp) < ERROR_MARGIN )
81 static gchar *parse_version_number(gchar *text)
87 for (i = 0; (s[i] != '\\') && (i < 8); i++)
93 return vers = g_strndup(s, i);
96 static const gchar *google_version_number(MapCoord *mapcoord, GoogleType google_type)
98 static gboolean first = TRUE;
99 static char *vers[] = { "w2.60", "w2t.60", "20" };
105 gchar *text, *pat, *beg;
108 gchar *gvers, *tvers, *kvers, *tmpvers;
109 static DownloadOptions dl_options = { "http://maps.google.com/", 0 };
110 static const char *gvers_pat = "http://mt0.google.com/mt?n\\x3d404\\x26v\\x3d";
111 static const char *kvers_pat = "http://kh0.google.com/kh?n\\x3d404\\x26v\\x3d";
113 g_assert(google_type < TYPE_GOOGLE_NUM);
116 return (vers[google_type]);
120 gvers = tvers = kvers = NULL;
121 if ((tmp_fd = g_file_open_tmp ("vikgvers.XXXXXX", &tmpname, NULL)) == -1) {
122 g_critical("couldn't open temp file %s\n", tmpname);
126 google_mapcoord_to_center_coord(mapcoord, &coord);
127 uri = g_strdup_printf("http://maps.google.com/maps?f=q&hl=en&q=%f,%f", coord.north_south, coord.east_west);
128 tmp_file = fdopen(tmp_fd, "r+");
130 if (curl_download_uri(uri, tmp_file, &dl_options)) { /* error */
131 g_warning("Failed downloading %s\n", tmpname);
133 if ((mf = g_mapped_file_new(tmpname, FALSE, NULL)) == NULL) {
134 g_critical("couldn't map temp file\n");
137 len = g_mapped_file_get_length(mf);
138 text = g_mapped_file_get_contents(mf);
140 if ((beg = g_strstr_len(text, len, "GLoadApi")) == NULL) {
141 g_warning("Failed fetching Google numbers (\"GLoadApi\" not found)\n");
146 while (!gvers || !tvers) {
147 if ((pat = g_strstr_len(pat, &text[len] - pat, gvers_pat)) != NULL) {
148 pat += strlen(gvers_pat);
149 if ((tmpvers = parse_version_number(pat)) != NULL) {
150 if (strstr(tmpvers, "t."))
160 if ((pat = g_strstr_len(beg, &text[len] - beg, kvers_pat)) != NULL)
161 kvers = parse_version_number(pat + strlen(kvers_pat));
163 if (gvers && tvers && kvers) {
164 vers[TYPE_GOOGLE_MAPS] = gvers;
165 vers[TYPE_GOOGLE_TRANS] = tvers;
166 vers[TYPE_GOOGLE_SAT] = kvers;
169 g_warning("Failed getting google version numbers");
172 fprintf(stderr, "DEBUG gvers=%s\n", gvers);
174 fprintf(stderr, "DEBUG tvers=%s\n", tvers);
176 fprintf(stderr, "DEBUG kvers=%s\n", kvers);
179 g_mapped_file_free(mf);
184 return (vers[google_type]);
187 gboolean google_coord_to_mapcoord ( const VikCoord *src, gdouble xzoom, gdouble yzoom, MapCoord *dest )
189 g_assert ( src->mode == VIK_COORD_LATLON );
191 if ( xzoom != yzoom )
194 dest->scale = google_zoom ( xzoom );
195 if ( dest->scale == 255 )
198 dest->x = (src->east_west + 180) / 360 * GZ(17) / xzoom;
199 dest->y = (180 - MERCLAT(src->north_south)) / 360 * GZ(17) / xzoom;
205 void google_mapcoord_to_center_coord ( MapCoord *src, VikCoord *dest )
207 gdouble socalled_mpp = GZ(src->scale);
208 dest->mode = VIK_COORD_LATLON;
209 dest->east_west = ((src->x+0.5) / GZ(17) * socalled_mpp * 360) - 180;
210 dest->north_south = DEMERCLAT(180 - ((src->y+0.5) / GZ(17) * socalled_mpp * 360));
213 static int real_google_download ( MapCoord *src, const gchar *dest_fn, const char *verstr )
216 gchar *uri = g_strdup_printf ( "/mt?n=404&v=%s&x=%d&y=%d&zoom=%d", verstr, src->x, src->y, src->scale );
217 res = a_http_download_get_url ( "mt.google.com", uri, dest_fn, &google_options );
222 static int google_download ( MapCoord *src, const gchar *dest_fn )
224 const gchar *vers_str = google_version_number(src, TYPE_GOOGLE_MAPS);
225 return(real_google_download ( src, dest_fn, vers_str ));
228 static int google_trans_download ( MapCoord *src, const gchar *dest_fn )
230 const gchar *vers_str = google_version_number(src, TYPE_GOOGLE_TRANS);
231 return(real_google_download ( src, dest_fn, vers_str ));
234 static char *kh_encode(guint32 x, guint32 y, guint8 scale)
236 gchar *buf = g_malloc ( (20-scale)*sizeof(gchar) );
237 guint32 ya = 1 << (17 - scale);
240 if (y < 0 || (ya-1 < y)) {
241 strcpy(buf,"tqq"); /* BAD */
244 if (x < 0 || ya-1 < x) {
251 for (j = 1, i = 16; i >= scale; i--, j++) {
275 static int google_kh_download ( MapCoord *src, const gchar *dest_fn )
278 gchar *khenc = kh_encode( src->x, src->y, src->scale );
279 const gchar *vers_str = google_version_number(src, TYPE_GOOGLE_SAT);
280 gchar *uri = g_strdup_printf ( "/kh?n=404&v=%s&t=%s", vers_str, khenc );
282 res = a_http_download_get_url ( "kh.google.com", uri, dest_fn, &google_options );