X-Git-Url: https://git.street.me.uk/andy/viking.git/blobdiff_plain/ce1c0489dcc4a2aeeab587b05ac872395107e4fd..0fa0c0b718943c7e50719fe516de88c3fd3ab6a8:/src/viktrack.c?ds=sidebyside

diff --git a/src/viktrack.c b/src/viktrack.c
index ae3110c5..8598090a 100644
--- a/src/viktrack.c
+++ b/src/viktrack.c
@@ -499,7 +499,12 @@ gdouble *vik_track_make_elevation_map ( const VikTrack *tr, guint16 num_chunks )
     gboolean okay = FALSE;
     while ( iter )
     {
-      if ( VIK_TRACKPOINT(iter->data)->altitude != VIK_DEFAULT_ALTITUDE ) {
+      // Sometimes a GPS device (or indeed any random file) can have stupid numbers for elevations
+      // Since when is 9.9999e+24 a valid elevation!!
+      // This can happen when a track (with no elevations) is uploaded to a GPS device and then redownloaded (e.g. using a Garmin Legend EtrexHCx)
+      // Some protection against trying to work with crazily massive numbers (otherwise get SIGFPE, Arithmetic exception)
+      if ( VIK_TRACKPOINT(iter->data)->altitude != VIK_DEFAULT_ALTITUDE &&
+	   VIK_TRACKPOINT(iter->data)->altitude < 1E9 ) {
         okay = TRUE; break;
       }
       iter = iter->next;
@@ -701,7 +706,7 @@ gdouble *vik_track_make_speed_map ( const VikTrack *tr, guint16 num_chunks )
   iter = tr->trackpoints->next;
   numpts = 0;
   s[0] = 0;
-  t[0] = VIK_TRACKPOINT(iter->prev->data)->timestamp;
+  t[0] = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
   numpts++;
   while (iter) {
     s[numpts] = s[numpts-1] + vik_coord_diff ( &(VIK_TRACKPOINT(iter->prev->data)->coord), &(VIK_TRACKPOINT(iter->data)->coord) );
@@ -775,7 +780,7 @@ gdouble *vik_track_make_distance_map ( const VikTrack *tr, guint16 num_chunks )
   iter = tr->trackpoints->next;
   numpts = 0;
   s[0] = 0;
-  t[0] = VIK_TRACKPOINT(iter->prev->data)->timestamp;
+  t[0] = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
   numpts++;
   while (iter) {
     s[numpts] = s[numpts-1] + vik_coord_diff ( &(VIK_TRACKPOINT(iter->prev->data)->coord), &(VIK_TRACKPOINT(iter->data)->coord) );
@@ -945,7 +950,7 @@ gdouble *vik_track_make_speed_dist_map ( const VikTrack *tr, guint16 num_chunks
   iter = tr->trackpoints->next;
   numpts = 0;
   s[0] = 0;
-  t[0] = VIK_TRACKPOINT(iter->prev->data)->timestamp;
+  t[0] = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
   numpts++;
   while (iter) {
     s[numpts] = s[numpts-1] + vik_coord_diff ( &(VIK_TRACKPOINT(iter->prev->data)->coord), &(VIK_TRACKPOINT(iter->data)->coord) );