Optimization

src/map/IMG/rastertile.cpp

@@ -466,8 +466,7 @@ MatrixD RasterTile::elevation(int extend) const
 	int top = _rect.top() - extend;
 	int bottom = _rect.bottom() + extend;
 
-	Matrix<Coordinates> ll(_rect.height() + 2 * extend,
-	  _rect.width() + 2 * extend);
+	MatrixC ll(_rect.height() + 2 * extend, _rect.width() + 2 * extend);
 	for (int y = top, i = 0; y <= bottom; y++)
 		for (int x = left; x <= right; x++, i++)
 			ll.at(i) = xy2ll(QPointF(x, y));
@@ -486,7 +485,6 @@ MatrixD RasterTile::elevation(int extend) const
 
 		DEMTree tree(tiles);
 		MatrixD m(ll.h(), ll.w());
-
 		for (int i = 0; i < ll.size(); i++)
 			m.at(i) = tree.elevation(ll.at(i));
 

src/map/dem.cpp

@@ -23,12 +23,20 @@
 
 static unsigned int isqrt(unsigned int x)
 {
-	unsigned int r = 0;
+	unsigned int l = 0;
+	unsigned int m;
+	unsigned int r = x + 1;
 
-	while ((r + 1) * (r + 1) <= x)
-		r++;
+	while (l != r - 1) {
+		m = (l + r) / 2;
 
-	return r;
+		if (m * m <= x)
+			l = m;
+		else
+			r = m;
+	}
+
+	return l;
 }
 
 static double interpolate(double dx, double dy, double p0, double p1, double p2,
@@ -46,7 +54,6 @@ static double value(int col, int row, int samples, const QByteArray &data)
 	return (val == -32768) ? NAN : val;
 }
 
-QMutex DEM::_lock;
 
 DEM::Entry::Entry(const QByteArray &data) : _data(data)
 {
@@ -70,6 +77,8 @@ QString DEM::Tile::fileName() const
 	return QString("%1%2.hgt").arg(latStr(), lonStr());
 }
 
+
+QMutex DEM::_lock;
 QString DEM::_dir;
 DEM::TileCache DEM::_data;
 
@@ -170,7 +179,7 @@ double DEM::elevationLockFree(const Coordinates &c)
 	return ele;
 }
 
-MatrixD DEM::elevation(const Matrix<Coordinates> &m)
+MatrixD DEM::elevation(const MatrixC &m)
 {
 	if (_dir.isEmpty())
 		return MatrixD(m.h(), m.w(), NAN);

src/map/dem.h

@@ -9,8 +9,6 @@
 #include "data/area.h"
 #include "matrix.h"
 
-class Coordinates;
-
 class DEM
 {
 public:
@@ -39,7 +37,7 @@ public:
 	static void clearCache();
 
 	static double elevation(const Coordinates &c);
-	static MatrixD elevation(const Matrix<Coordinates> &m);
+	static MatrixD elevation(const MatrixC &m);
 
 	static QList<Area> tiles();
 

src/map/mapsforge/rastertile.cpp

@@ -475,8 +475,7 @@ MatrixD RasterTile::elevation(int extend) const
 	int top = _rect.top() - extend;
 	int bottom = _rect.bottom() + extend;
 
-	Matrix<Coordinates> ll(_rect.height() + 2 * extend,
-	  _rect.width() + 2 * extend);
+	MatrixC ll(_rect.height() + 2 * extend, _rect.width() + 2 * extend);
 	for (int y = top, i = 0; y <= bottom; y++)
 		for (int x = left; x <= right; x++, i++)
 			ll.at(i) = xy2ll(QPointF(x, y));

src/map/matrix.h

@@ -5,6 +5,8 @@
 #include <QVector>
 #include <QDebug>
 
+class Coordinates;
+
 template <class T>
 class Matrix
 {
@@ -39,6 +41,8 @@ public:
 	MatrixD augemented(const MatrixD &M) const;
 };
 
+typedef Matrix<Coordinates> MatrixC;
+
 #ifndef QT_NO_DEBUG
 template <class T>
 inline QDebug operator<<(QDebug dbg, const Matrix<T> &matrix)