src/terraserver.c

   1 /*
   2  * viking -- GPS Data and Topo Analyzer, Explorer, and Manager
   3  *
   4  * Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.net>
   5  *
   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.
  10  *
  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.
  15  *
  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
  19  *
  20  */
  21
  22 #include <gtk/gtk.h>
  23 #include <math.h>
  24 #include "viking.h"
  25 #include "coords.h"
  26 #include "vikcoord.h"
  27 #include "mapcoord.h"
  28 #include "download.h"
  29 #include "vikmapslayer.h"
  30
  31 #include "terraserver.h"
  32
  33 static gboolean terraserver_topo_coord_to_mapcoord ( const VikCoord *src, gdouble xmpp, gdouble ympp, MapCoord *dest );
  34 static int terraserver_topo_download ( MapCoord *src, const gchar *dest_fn );
  35
  36 static gboolean terraserver_aerial_coord_to_mapcoord ( const VikCoord *src, gdouble xmpp, gdouble ympp, MapCoord *dest );
  37 static int terraserver_aerial_download ( MapCoord *src, const gchar *dest_fn );
  38
  39 static gboolean terraserver_urban_coord_to_mapcoord ( const VikCoord *src, gdouble xmpp, gdouble ympp, MapCoord *dest );
  40 static int terraserver_urban_download ( MapCoord *src, const gchar *dest_fn );
  41
  42 static void terraserver_mapcoord_to_center_coord ( MapCoord *src, VikCoord *dest );
  43
  44 static DownloadOptions terraserver_options = { 0 };
  45
  46 void terraserver_init () {
  47   VikMapsLayer_MapType map_type_1 = { 2, 200, 200, VIK_VIEWPORT_DRAWMODE_UTM, terraserver_topo_coord_to_mapcoord, terraserver_mapcoord_to_center_coord, terraserver_topo_download };
  48   VikMapsLayer_MapType map_type_2 = { 1, 200, 200, VIK_VIEWPORT_DRAWMODE_UTM, terraserver_aerial_coord_to_mapcoord, terraserver_mapcoord_to_center_coord, terraserver_aerial_download };
  49   VikMapsLayer_MapType map_type_3 = { 4, 200, 200, VIK_VIEWPORT_DRAWMODE_UTM, terraserver_urban_coord_to_mapcoord, terraserver_mapcoord_to_center_coord, terraserver_urban_download };
  50
  51   maps_layer_register_type("Terraserver Topos", 2, &map_type_1);
  52   maps_layer_register_type("Terraserver Aerials", 1, &map_type_2);
  53   maps_layer_register_type("Terraserver Urban Areas", 4, &map_type_3);
  54 }
  55
  56 #define TERRASERVER_SITE "terraserver-usa.com"
  57 #define MARGIN_OF_ERROR 0.001
  58
  59 static int mpp_to_scale ( gdouble mpp, guint8 type )
  60 {
  61   mpp *= 4;
  62   gint t = (gint) mpp;
  63   if ( ABS(mpp - t) > MARGIN_OF_ERROR )
  64     return FALSE;
  65
  66   switch ( t ) {
  67     case 1: return (type == 4) ? 8 : 0;
  68     case 2: return (type == 4) ? 9 : 0;
  69     case 4: return (type != 2) ? 10 : 0;
  70     case 8: return 11;
  71     case 16: return 12;
  72     case 32: return 13;
  73     case 64: return 14;
  74     case 128: return 15;
  75     case 256: return 16;
  76     case 512: return 17;
  77     case 1024: return 18;
  78     case 2048: return 19;
  79     default: return 0;
  80   }
  81 }
  82
  83 static gdouble scale_to_mpp ( gint scale )
  84 {
  85   return pow(2,scale - 10);
  86 }
  87
  88 static gboolean terraserver_coord_to_mapcoord ( const VikCoord *src, gdouble xmpp, gdouble ympp, MapCoord *dest, guint8 type )
  89 {
  90   g_assert ( src->mode == VIK_COORD_UTM );
  91
  92   if ( xmpp != ympp )
  93     return FALSE;
  94
  95   dest->scale = mpp_to_scale ( xmpp, type );
  96   if ( ! dest->scale )
  97     return FALSE;
  98
  99   dest->x = (gint)(((gint)(src->east_west))/(200*xmpp));
 100   dest->y = (gint)(((gint)(src->north_south))/(200*xmpp));
 101   dest->z = src->utm_zone;
 102   return TRUE;
 103 }
 104
 105 static gboolean terraserver_topo_coord_to_mapcoord ( const VikCoord *src, gdouble xmpp, gdouble ympp, MapCoord *dest )
 106 { return terraserver_coord_to_mapcoord ( src, xmpp, ympp, dest, 2 ); }
 107 static gboolean terraserver_aerial_coord_to_mapcoord ( const VikCoord *src, gdouble xmpp, gdouble ympp, MapCoord *dest )
 108 { return terraserver_coord_to_mapcoord ( src, xmpp, ympp, dest, 1 ); }
 109 static gboolean terraserver_urban_coord_to_mapcoord ( const VikCoord *src, gdouble xmpp, gdouble ympp, MapCoord *dest )
 110 { return terraserver_coord_to_mapcoord ( src, xmpp, ympp, dest, 4 ); }
 111
 112 static void terraserver_mapcoord_to_center_coord ( MapCoord *src, VikCoord *dest )
 113 {
 114   // FIXME: slowdown here!
 115   gdouble mpp = scale_to_mpp ( src->scale );
 116   dest->mode = VIK_COORD_UTM;
 117   dest->utm_zone = src->z;
 118   dest->east_west = ((src->x * 200) + 100) * mpp;
 119   dest->north_south = ((src->y * 200) + 100) * mpp;
 120 }
 121
 122 static int terraserver_download ( MapCoord *src, const gchar *dest_fn, guint8 type )
 123 {
 124   int res = -1;
 125   gchar *uri = g_strdup_printf ( "/tile.ashx?T=%d&S=%d&X=%d&Y=%d&Z=%d", type,
 126                                   src->scale, src->x, src->y, src->z );
 127   res = a_http_download_get_url ( TERRASERVER_SITE, uri, dest_fn, &terraserver_options );
 128   g_free ( uri );
 129   return(res);
 130 }
 131
 132 static int terraserver_topo_download ( MapCoord *src, const gchar *dest_fn )
 133 { return terraserver_download ( src, dest_fn, 2 ); }
 134 static int terraserver_aerial_download ( MapCoord *src, const gchar *dest_fn )
 135 { return terraserver_download ( src, dest_fn, 1 ); }
 136 static int terraserver_urban_download ( MapCoord *src, const gchar *dest_fn )
 137 { return terraserver_download ( src, dest_fn, 4 ); }