bug fixed for RIO network

src/main/java/environment/RIOBasinNetworkObserverWithContinent.java

@@ -193,7 +193,7 @@ public class RIOBasinNetworkObserverWithContinent extends ObserverListener
 
 			maxX = maxY = Double.NEGATIVE_INFINITY;
 			minX = minY = Double.POSITIVE_INFINITY;
-			mapContinent = ((BasinNetworkSWithContinent) pilot.getAquaticWorld().getEnvironment()).getMapContinent();
+			mapContinent = ((RIOBasinNetworkWithContinent) pilot.getAquaticWorld().getEnvironment()).getMapContinent();
 			for (Path2D.Double path : mapContinent.values()) {
 				minX = Math.min(minX, path.getBounds2D().getMinX());
 				maxX = Math.max(maxX, path.getBounds2D().getMaxX());