src/gpx.cc

   1 /* gpx.cc
   2  * Export from Aven as GPX.
   3  */
   4 /* Copyright (C) 2012 Olaf Kähler
   5  * Copyright (C) 2012,2013,2014,2015,2016 Olly Betts
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 # include <config.h>
  24 #endif
  25
  26 #include "gpx.h"
  27
  28 #include "export.h" // For LABELS, etc
  29
  30 #include <stdio.h>
  31 #include <string>
  32 #include <time.h>
  33 #include <math.h>
  34
  35 #include "useful.h"
  36 #include <proj.h>
  37
  38 #include "aven.h"
  39 #include "message.h"
  40
  41 using namespace std;
  42
  43 #define WGS84_DATUM_STRING "EPSG:4326"
  44
  45 static void
  46 html_escape(FILE *fh, const char *s)
  47 {
  48     while (*s) {
  49         switch (*s) {
  50             case '<':
  51                 fputs("&lt;", fh);
  52                 break;
  53             case '>':
  54                 fputs("&gt;", fh);
  55                 break;
  56             case '&':
  57                 fputs("&amp;", fh);
  58                 break;
  59             default:
  60                 PUTC(*s, fh);
  61         }
  62         ++s;
  63     }
  64 }
  65
  66 static void discarding_proj_logger(void *, int, const char *) { }
  67
  68 GPX::GPX(const char * input_datum)
  69 {
  70     /* Prevent stderr spew from PROJ. */
  71     proj_log_func(PJ_DEFAULT_CTX, nullptr, discarding_proj_logger);
  72
  73     pj = proj_create_crs_to_crs(PJ_DEFAULT_CTX,
  74                                 input_datum, WGS84_DATUM_STRING,
  75                                 NULL);
  76
  77     if (pj) {
  78         // Normalise the output order so x is longitude and y latitude - by
  79         // default new PROJ has them switched for EPSG:4326 which just seems
  80         // confusing.
  81         PJ* pj_norm = proj_normalize_for_visualization(PJ_DEFAULT_CTX, pj);
  82         proj_destroy(pj);
  83         pj = pj_norm;
  84     }
  85
  86     if (!pj) {
  87         wxString m = wmsg(/*Failed to initialise input coordinate system “%s”*/287);
  88         m = wxString::Format(m.c_str(), input_datum);
  89         throw m;
  90     }
  91 }
  92
  93 GPX::~GPX()
  94 {
  95     if (pj)
  96         proj_destroy(pj);
  97     free((void*)trk_name);
  98 }
  99
 100 const int *
 101 GPX::passes() const
 102 {
 103     static const int default_passes[] = { LABELS|ENTS|FIXES|EXPORTS, LEGS|SURF, 0 };
 104     return default_passes;
 105 }
 106
 107 /* Initialise GPX routines. */
 108 void GPX::header(const char * title, const char *, time_t datestamp_numeric,
 109                  double, double, double, double, double, double)
 110 {
 111     fputs(
 112 "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
 113 "<gpx version=\"1.0\" creator=\"" PACKAGE_STRING " (aven) - https://survex.com/\""
 114 " xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\""
 115 " xmlns=\"http://www.topografix.com/GPX/1/0\""
 116 " xsi:schemaLocation=\"http://www.topografix.com/GPX/1/0"
 117 " http://www.topografix.com/GPX/1/0/gpx.xsd\">\n", fh);
 118     if (title) {
 119         fputs("<name>", fh);
 120         html_escape(fh, title);
 121         fputs("</name>\n", fh);
 122         trk_name = strdup(title);
 123     }
 124     if (datestamp_numeric != time_t(-1)) {
 125         struct tm * tm = gmtime(&datestamp_numeric);
 126         if (tm) {
 127             char buf[32];
 128             if (strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%SZ", tm)) {
 129                 fputs("<time>", fh);
 130                 fputs(buf, fh);
 131                 fputs("</time>\n", fh);
 132             }
 133         }
 134     }
 135     // FIXME: optional in GPX, but perhaps useful:
 136     // <bounds minlat="..." minlon="..." maxlat="..." maxlon="..." />
 137     // NB Not necessarily the same as the bounds in survex coords translated
 138     // to WGS84 lat+long...
 139 }
 140
 141 void
 142 GPX::line(const img_point *p1, const img_point *p, unsigned /*flags*/, bool fPendingMove)
 143 {
 144     if (fPendingMove) {
 145         if (in_trkseg) {
 146             fputs("</trkseg><trkseg>\n", fh);
 147         } else {
 148             fputs("<trk>", fh);
 149             if (trk_name) {
 150                 fputs("<name>", fh);
 151                 html_escape(fh, trk_name);
 152                 fputs("</name>", fh);
 153             }
 154             fputs("<trkseg>\n", fh);
 155             in_trkseg = true;
 156         }
 157         PJ_COORD coord = {p1->x, p1->y, p1->z, HUGE_VAL};
 158         coord = proj_trans(pj, PJ_FWD, coord);
 159         if (coord.xyzt.x == HUGE_VAL ||
 160             coord.xyzt.y == HUGE_VAL ||
 161             coord.xyzt.z == HUGE_VAL) {
 162             // FIXME report errors
 163         }
 164         // %.8f is at worst just over 1mm.
 165         fprintf(fh, "<trkpt lon=\"%.8f\" lat=\"%.8f\"><ele>%.2f</ele></trkpt>\n",
 166                 coord.xyzt.x,
 167                 coord.xyzt.y,
 168                 coord.xyzt.z);
 169     }
 170
 171     PJ_COORD coord = {p->x, p->y, p->z, HUGE_VAL};
 172     coord = proj_trans(pj, PJ_FWD, coord);
 173     if (coord.xyzt.x == HUGE_VAL ||
 174         coord.xyzt.y == HUGE_VAL ||
 175         coord.xyzt.z == HUGE_VAL) {
 176         // FIXME report errors
 177     }
 178     // %.8f is at worst just over 1mm.
 179     fprintf(fh, "<trkpt lon=\"%.8f\" lat=\"%.8f\"><ele>%.2f</ele></trkpt>\n",
 180             coord.xyzt.x,
 181             coord.xyzt.y,
 182             coord.xyzt.z);
 183 }
 184
 185 void
 186 GPX::label(const img_point *p, const char *s, bool /*fSurface*/, int type)
 187 {
 188     PJ_COORD coord = {p->x, p->y, p->z, HUGE_VAL};
 189     coord = proj_trans(pj, PJ_FWD, coord);
 190     if (coord.xyzt.x == HUGE_VAL ||
 191         coord.xyzt.y == HUGE_VAL ||
 192         coord.xyzt.z == HUGE_VAL) {
 193         // FIXME report errors
 194     }
 195     // %.8f is at worst just over 1mm.
 196     fprintf(fh, "<wpt lon=\"%.8f\" lat=\"%.8f\"><ele>%.2f</ele><name>",
 197             coord.xyzt.x,
 198             coord.xyzt.y,
 199             coord.xyzt.z);
 200     html_escape(fh, s);
 201     fputs("</name>", fh);
 202     // Add a "pin" symbol with colour matching what aven shows.
 203     switch (type) {
 204         case FIXES:
 205             fputs("<sym>Pin, Red</sym>", fh);
 206             break;
 207         case EXPORTS:
 208             fputs("<sym>Pin, Blue</sym>", fh);
 209             break;
 210         case ENTS:
 211             fputs("<sym>Pin, Green</sym>", fh);
 212             break;
 213     }
 214     fputs("</wpt>\n", fh);
 215 }
 216
 217 void
 218 GPX::footer()
 219 {
 220     if (in_trkseg)
 221         fputs("</trkseg></trk>\n", fh);
 222     fputs("</gpx>\n", fh);
 223 }