new helper methods

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

mapview/2D/MV2DElementFloorObstacleDoor.h

@@ -27,7 +27,7 @@ public:
 	}
 
 	/** get the element's minimal distance (nearest whatsoever) to the given point */
-	float getMinDistanceXY(const Point2 p) const override {
+	ClickDist getMinDistanceXY(const Point2 p) const override {
 		return MapElementHelper::getLineDistanceXY(fo->from, fo->to, p);
 	}
 
@@ -69,6 +69,12 @@ public:
 			p.drawCircle(fo->to);
 		}
 
+		// obstacle length
+		if (hasFocus()) {
+			p.setPenBrush(Qt::black, Qt::NoBrush);
+			p.drawLength(fo->from, fo->to, fo->from.getDistance(fo->to));
+		}
+
 	}