diff --git a/src/map/IMG/demtree.cpp b/src/map/IMG/demtree.cpp
index b8863181..d94df078 100644
--- a/src/map/IMG/demtree.cpp
+++ b/src/map/IMG/demtree.cpp
@@ -111,3 +111,13 @@ double DEMTree::elevation(const Coordinates &c) const
 
 	return ele;
 }
+
+MatrixD DEMTree::elevation(const MatrixC &m) const
+{
+	MatrixD ret(m.h(), m.w());
+
+	for (int i = 0; i < m.size(); i++)
+		ret.at(i) = elevation(m.at(i));
+
+	return ret;
+}
diff --git a/src/map/IMG/demtree.h b/src/map/IMG/demtree.h
index 9e78b302..86ff7139 100644
--- a/src/map/IMG/demtree.h
+++ b/src/map/IMG/demtree.h
@@ -2,6 +2,7 @@
 #define IMG_DEMTREE_H
 
 #include "common/rtree.h"
+#include "map/matrix.h"
 #include "mapdata.h"
 
 namespace IMG {
@@ -11,6 +12,7 @@ public:
 	DEMTree(const QList<MapData::Elevation> &tiles);
 
 	double elevation(const Coordinates &c) const;
+	MatrixD elevation(const MatrixC &m) const;
 
 private:
 	typedef RTree<const MapData::Elevation*, double, 2> Tree;
diff --git a/src/map/IMG/rastertile.cpp b/src/map/IMG/rastertile.cpp
index af8d51a3..be67893b 100644
--- a/src/map/IMG/rastertile.cpp
+++ b/src/map/IMG/rastertile.cpp
@@ -483,22 +483,18 @@ MatrixD RasterTile::elevation(int extend) const
 
 	if (_data->hasDEM()) {
 		RectC rect;
-		QList<MapData::Elevation> tiles;
-
 		for (int i = 0; i < ll.size(); i++)
 			rect = rect.united(ll.at(i));
-		// Extra margin for always including the next DEM tile on the map tile
-		// edges (the DEM tile resolution is usally 0.5-15% of the map tile)
+		/* Extra margin for always including the next DEM tile on the map tile
+		   edges (the DEM tile resolution is usally 0.5-15% of the map tile) */
 		double factor = 6 - (_zoom - 24) * 1.7;
-		_data->elevations(_file, rect.adjusted(0, 0, rect.width() / factor,
-		  -rect.height() / factor), _zoom, &tiles);
+		RectC br(rect.adjusted(0, 0, rect.width() / factor, -rect.height()
+		  / factor));
 
-		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));
+		QList<MapData::Elevation> tiles;
+		_data->elevations(_file, br, _zoom, &tiles);
 
-		return m;
+		return DEMTree(tiles).elevation(ll);
 	} else
 		return DEM::elevation(ll);
 }