Sea level logic updated.

src/engine/objects/Zone.java

@@ -247,8 +247,15 @@ public class Zone extends AbstractGameObject {
         // Zone AABB is set here as it's coordinate space is world requiring a parent.
         this.setBounds();
 
+        if (ZoneManager.getSeaFloor().equals(this)) {
+            this.seaLevel = 0;
+            return;
+        }
+
         if (this.getHeightMap() != null && this.getHeightMap().getSeaLevel() != 0)
-            this.seaLevel = this.getHeightMap().getSeaLevel();
+            this.seaLevel = this.worldAltitude + this.getHeightMap().getSeaLevel();
+        else
+            this.seaLevel = this.parent.seaLevel;
 
     }