X-Git-Url: https://git.street.me.uk/andy/viking.git/blobdiff_plain/50a14534a51f892500ee82f867e8ab2f85b936ae..dade5f874b05c2263bbbe668a77021d487b0761b:/src/vikcoord.c?ds=inline

diff --git a/src/vikcoord.c b/src/vikcoord.c
index a805e4a7..c61f30ec 100644
--- a/src/vikcoord.c
+++ b/src/vikcoord.c
@@ -27,7 +27,7 @@
 
 void vik_coord_convert(VikCoord *coord, VikCoordMode dest_mode)
 {
-  static VikCoord tmp;
+  VikCoord tmp;
   if ( coord->mode != dest_mode )
   {
     if ( dest_mode == VIK_COORD_LATLON ) {
@@ -56,7 +56,7 @@ void vik_coord_copy_convert(const VikCoord *coord, VikCoordMode dest_mode, VikCo
 
 static gdouble vik_coord_diff_safe(const VikCoord *c1, const VikCoord *c2)
 {
-  static struct LatLon a, b;
+  struct LatLon a, b;
   vik_coord_to_latlon ( c1, &a );
   vik_coord_to_latlon ( c2, &b );
   return a_coords_latlon_diff ( &a, &b );
@@ -115,3 +115,59 @@ gboolean vik_coord_equals ( const VikCoord *coord1, const VikCoord *coord2 )
   else /* VIK_COORD_UTM */
     return coord1->utm_zone == coord2->utm_zone && coord1->north_south == coord2->north_south && coord1->east_west == coord2->east_west;
 }
+
+static void get_north_west(struct LatLon *center, struct LatLon *dist, struct LatLon *nw) 
+{
+  nw->lat = center->lat + dist->lat;
+  nw->lon = center->lon - dist->lon;
+  if (nw->lon < -180)
+    nw->lon += 360.0;
+  if (nw->lat > 90.0) {  /* over north pole */
+    nw->lat = 180 - nw->lat;
+    nw->lon = nw->lon - 180;
+  }
+}
+
+static void get_south_east(struct LatLon *center, struct LatLon *dist, struct LatLon *se) 
+{
+  se->lat = center->lat - dist->lat;
+  se->lon = center->lon + dist->lon;
+  if (se->lon > 180.0)
+    se->lon -= 360.0;
+  if (se->lat < -90.0) {  /* over south pole */
+    se->lat += 180;
+    se->lon = se->lon - 180;
+  }
+}
+
+void vik_coord_set_area(const VikCoord *coord, const struct LatLon *wh, VikCoord *tl, VikCoord *br)
+{
+  struct LatLon center, nw, se;
+  struct LatLon dist;
+
+  dist.lat = wh->lat/2;
+  dist.lon = wh->lon/2;
+
+  vik_coord_to_latlon(coord, &center);
+  get_north_west(&center, &dist, &nw);
+  get_south_east(&center, &dist, &se);
+
+  *((struct LatLon *)tl) = nw;
+  *((struct LatLon *)br) = se;
+  tl->mode = br->mode = VIK_COORD_LATLON;
+}
+
+gboolean vik_coord_inside(const VikCoord *coord, const VikCoord *tl, const VikCoord *br)
+{
+  struct LatLon ll, tl_ll, br_ll;
+
+  vik_coord_to_latlon(coord, &ll);
+  vik_coord_to_latlon(tl, &tl_ll);
+  vik_coord_to_latlon(br, &br_ll);
+
+  if ((ll.lat > tl_ll.lat) || (ll.lon < tl_ll.lon))
+    return FALSE;
+  if ((ll.lat  < br_ll.lat) || (ll.lon > br_ll.lon))
+    return FALSE;
+  return TRUE;
+}