X-Git-Url: https://git.street.me.uk/andy/viking.git/blobdiff_plain/50a14534a51f892500ee82f867e8ab2f85b936ae..f5f53833288f037fee5e21a39b4d6ddf005994db:/src/coords.c

diff --git a/src/coords.c b/src/coords.c
index df2391bc..25eb900c 100644
--- a/src/coords.c
+++ b/src/coords.c
@@ -6,6 +6,8 @@ I (Evan Battaglia <viking@greentorch.org>) have only made some small changes suc
 renaming functions and defining LatLon and UTM structs.
 2004-02-10 -- I also added a function of my own -- a_coords_utm_diff() -- that I felt belonged in coords.c
 2004-02-21 -- I also added a_coords_utm_equal().
+2005-11-23 -- Added a_coords_dtostr() for lack of a better place.
+
 */
 /* coords.h - include file for coords routines
 **
@@ -33,16 +35,38 @@ renaming functions and defining LatLon and UTM structs.
 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 ** SUCH DAMAGE.
 */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
 
+#ifdef HAVE_STDLIB_H
 #include <stdlib.h>
+#endif
+#ifdef HAVE_STRING_H
 #include <string.h>
+#endif
+#ifdef HAVE_MATH_H
 #include <math.h>
+#endif
 
 #include "viking.h"
+#include "globals.h"
+#include "degrees_converters.h"
 
-#ifdef WINDOWS
-#define M_PI 3.14159265358979
-#endif
+/**
+ * Convert a double to a string WITHOUT LOCALE.
+ *
+ * Following GPX specifications, decimal values are xsd:decimal
+ * So, they must use the period separator, not the localized one.
+ *
+ * The returned value must be freed by g_free.
+ */
+char *a_coords_dtostr ( double d )
+{
+  gchar *buffer = g_malloc(G_ASCII_DTOSTR_BUF_SIZE*sizeof(gchar));
+  g_ascii_dtostr (buffer, G_ASCII_DTOSTR_BUF_SIZE, (gdouble) d);
+  return buffer;
+}
 
 #define PIOVER180 0.01745329252
 
@@ -74,11 +98,14 @@ double a_coords_utm_diff( const struct UTM *utm1, const struct UTM *utm2 )
 double a_coords_latlon_diff ( const struct LatLon *ll1, const struct LatLon *ll2 )
 {
   static struct LatLon tmp1, tmp2;
+  gdouble tmp3;
   tmp1.lat = ll1->lat * PIOVER180;
   tmp1.lon = ll1->lon * PIOVER180;
   tmp2.lat = ll2->lat * PIOVER180;
   tmp2.lon = ll2->lon * PIOVER180;
-  return EquatorialRadius * acos(sin(tmp1.lat)*sin(tmp2.lat)+cos(tmp1.lat)*cos(tmp2.lat)*cos(tmp1.lon-tmp2.lon));
+  tmp3 = EquatorialRadius * acos(sin(tmp1.lat)*sin(tmp2.lat)+cos(tmp1.lat)*cos(tmp2.lat)*cos(tmp1.lon-tmp2.lon));
+  // For very small differences we can sometimes get NaN returned
+  return isnan(tmp3)?0:tmp3;
 }
 
 void a_coords_latlon_to_utm( const struct LatLon *latlon, struct UTM *utm )
@@ -222,3 +249,29 @@ void a_coords_utm_to_latlon( const struct UTM *utm, struct LatLon *latlon )
     latlon->lon = longitude;
 
     }
+
+void a_coords_latlon_to_string ( const struct LatLon *latlon,
+				 gchar **lat,
+				 gchar **lon )
+{
+  g_return_if_fail ( latlon != NULL );
+
+  vik_degree_format_t format = a_vik_get_degree_format ();
+
+  switch (format) {
+  case VIK_DEGREE_FORMAT_DDD:
+    *lat = convert_lat_dec_to_ddd ( latlon->lat );
+    *lon = convert_lon_dec_to_ddd ( latlon->lon );
+    break;
+  case VIK_DEGREE_FORMAT_DMM:
+    *lat = convert_lat_dec_to_dmm ( latlon->lat );
+    *lon = convert_lon_dec_to_dmm ( latlon->lon );
+    break;
+  case VIK_DEGREE_FORMAT_DMS:
+    *lat = convert_lat_dec_to_dms ( latlon->lat );
+    *lon = convert_lon_dec_to_dms ( latlon->lon );
+    break;
+  default:
+    g_critical("Houston, we've had a problem. format=%d", format);
+  }
+}