new helper methods

improved elememt-selection
changed some parameters
show length for selected obstacles/doors
minor fixes

mapview/2D/MV2DElementPOI.h

@@ -30,8 +30,8 @@ public:
 	}
 
 	/** get the element's minimal distance (nearest whatsoever) to the given point */
-	float getMinDistanceXY(const Point2 p) const override {
-		return p.getDistance(poi->pos);
+	ClickDist getMinDistanceXY(const Point2 p) const override {
+		return ClickDist(p.getDistance(poi->pos), ClickDistType::DIRECT);
 	}
 
 	/** repaint me */