cleanup: move tile value comparisons into TileConstants class

git-svn-id: https://micropolis.googlecode.com/svn/trunk/micropolis-java@688 d9718cc8-9f43-0410-858b-315f434eb58c

src/micropolisj/engine/MapScanner.java

@@ -428,30 +428,31 @@ class MapScanner
 			city.unpoweredZoneCount++;
 		}
 
-		if (cchr9 > PORTBASE)
+		if (isSpecialZone(cchr))
 		{
 			doSpecialZone(zonePwrFlag);
 			return;
 		}
 
-		if (cchr9 < HOSPITAL)
+		if (isResidentialZone(cchr))
 		{
 			doResidential(zonePwrFlag);
 			return;
 		}
 
-		if (cchr9 < COMBASE)
+		if (isHospitalOrChurch(cchr))
 		{
 			doHospitalChurch(zonePwrFlag);
 			return;
 		}
 
-		if (cchr9 < INDBASE)
+		if (isCommercialZone(cchr))
 		{
 			doCommercial(zonePwrFlag);
 			return;
 		}
 
+		assert isIndustrialZone(cchr);
 		doIndustrial(zonePwrFlag);
 		return;
 	}

src/micropolisj/engine/TileConstants.java

@@ -428,6 +428,39 @@ public class TileConstants
 		return (tmp >= RAILBASE && tmp < RESBASE);
 	}
 
+	public static boolean isCommercialZone(int tile)
+	{
+		assert isZoneCenter(tile);
+		return (tile & LOMASK) >= COMBASE &&
+			(tile & LOMASK) < INDBASE;
+	}
+
+	public static boolean isHospitalOrChurch(int tile)
+	{
+		assert isZoneCenter(tile);
+		return (tile & LOMASK) >= HOSPITAL &&
+			(tile & LOMASK) < COMBASE;
+	}
+
+	public static boolean isIndustrialZone(int tile)
+	{
+		assert isZoneCenter(tile);
+		return (tile & LOMASK) >= INDBASE &&
+			(tile & LOMASK) < PORTBASE;
+	}
+
+	public static boolean isResidentialZone(int tile)
+	{
+		assert isZoneCenter(tile);
+		return (tile & LOMASK) < HOSPITAL;
+	}
+
+	public static boolean isSpecialZone(int tile)
+	{
+		assert isZoneCenter(tile);
+		return (tile & LOMASK) >= PORTBASE;
+	}
+
 	public static boolean isZoneCenter(int tile)
 	{
 		return tile >= 0 && (tile & ZONEBIT) != 0;