src/coordinates.cpp

   1 #include "rd.h"
   2 #include "wgs84.h"
   3 #include "coordinates.h"
   4
   5 #define MIN_LAT deg2rad(-90.0)
   6 #define MAX_LAT deg2rad(90.0)
   7 #define MIN_LON deg2rad(-180.0)
   8 #define MAX_LON deg2rad(180.0)
   9
  10 qreal Coordinates::distanceTo(const Coordinates &c) const
  11 {
  12         qreal dLat = deg2rad(c.lat() - _lat);
  13         qreal dLon = deg2rad(c.lon() - _lon);
  14         qreal a = pow(sin(dLat / 2.0), 2.0)
  15           + cos(deg2rad(_lat)) * cos(deg2rad(c.lat())) * pow(sin(dLon / 2.0), 2.0);
  16
  17         return (WGS84_RADIUS * (2.0 * atan2(sqrt(a), sqrt(1.0 - a))));
  18 }
  19
  20 QPointF Coordinates::toMercator() const
  21 {
  22         return QPointF(_lon, rad2deg(log(tan(M_PI/4.0 + deg2rad(_lat)/2.0))));
  23 }
  24
  25 Coordinates Coordinates::fromMercator(const QPointF &m)
  26 {
  27         return Coordinates(m.x(), rad2deg(2 * atan(exp(deg2rad(m.y()))) - M_PI/2));
  28 }
  29
  30 bool operator==(const Coordinates &c1, const Coordinates &c2)
  31 {
  32         return (c1.lat() == c2.lat() && c1.lon() == c2.lon());
  33 }
  34
  35 QDebug operator<<(QDebug dbg, const Coordinates &coordinates)
  36 {
  37         dbg.nospace() << "Coordinates(" << coordinates.lon() << ", "
  38           << coordinates.lat() << ")";
  39
  40         return dbg.maybeSpace();
  41 }
  42
  43 QPair<Coordinates, Coordinates> Coordinates::boundingRect(qreal distance) const
  44 {
  45         qreal radDist = distance / WGS84_RADIUS;
  46
  47         qreal minLat = deg2rad(_lat) - radDist;
  48         qreal maxLat = deg2rad(_lat) + radDist;
  49
  50         qreal minLon, maxLon;
  51         if (minLat > MIN_LAT && maxLat < MAX_LAT) {
  52                 qreal deltaLon = asin(sin(radDist) / cos(_lat));
  53                 minLon = deg2rad(_lon) - deltaLon;
  54                 if (minLon < MIN_LON)
  55                         minLon += 2.0 * M_PI;
  56                 maxLon = deg2rad(_lon) + deltaLon;
  57                 if (maxLon > MAX_LON)
  58                         maxLon -= 2.0 * M_PI;
  59         } else {
  60                 // a pole is within the distance
  61                 minLat = qMax(minLat, MIN_LAT);
  62                 maxLat = qMin(maxLat, MAX_LAT);
  63                 minLon = MIN_LON;
  64                 maxLon = MAX_LON;
  65         }
  66
  67         return QPair<Coordinates, Coordinates>(Coordinates(rad2deg(qMin(minLon,
  68           maxLon)), rad2deg(qMin(minLat, maxLat))), Coordinates(rad2deg(qMax(minLon,
  69           maxLon)), rad2deg(qMax(minLat, maxLat))));
  70 }