diff --git a/src/map/mapsforge/mapdata.cpp b/src/map/mapsforge/mapdata.cpp index b365d4a9..f902b7f3 100644 --- a/src/map/mapsforge/mapdata.cpp +++ b/src/map/mapsforge/mapdata.cpp @@ -20,18 +20,19 @@ using namespace Mapsforge; #define KEY_ELE "ele" -static Coordinates centroid(const Polygon &polygon) +static Coordinates centroid(const QVector &v) { double area = 0; double cx = 0, cy = 0; - const QVector &v = polygon.first(); - for (int i = 0; i < v.count(); i++) { - int j = (i == v.count() - 1) ? 0 : i + 1; - double f = (v.at(i).lon() * v.at(j).lat() - v.at(j).lon() * v.at(i).lat()); + for (int i = 0; i < v.count() - 1; i++) { + const Coordinates &ci = v.at(i); + const Coordinates &cj = v.at(i+1); + double f = (ci.lon() * cj.lat() - cj.lon() * ci.lat()); + area += f; - cx += (v.at(i).lon() + v.at(j).lon()) * f; - cy += (v.at(i).lat() + v.at(j).lat()) * f; + cx += (ci.lon() + cj.lon()) * f; + cy += (ci.lat() + cj.lat()) * f; } double factor = 1.0 / (3.0 * area); @@ -710,7 +711,7 @@ bool MapData::readPaths(const VectorTile *tile, int zoom, QList *list) p.point.coordinates = Coordinates(outline.first().lon() + MD(lon), outline.first().lat() + MD(lat)); else if (p.closed) - p.point.coordinates = centroid(p.poly); + p.point.coordinates = centroid(outline); list->append(p); }