Fix warnings about updating empty maps

core/src/main/java/com/seibel/distanthorizons/core/dataObjects/fullData/FullDataPointIdMap.java

@@ -61,7 +61,6 @@ public class FullDataPointIdMap
 	private static final String BLOCK_STATE_SEPARATOR_STRING = "_DH-BSW_";
 	
 	
-	// FIXME: Improve performance maybe?
 	/** used when the data point map is running normally */
 	private final ReentrantReadWriteLock readWriteLock = new ReentrantReadWriteLock();
 	
@@ -118,6 +117,7 @@ public class FullDataPointIdMap
 	
 	/** @return -1 if the list is empty */
 	public int getMaxValidId() { return this.entryList.size() - 1; }
+	public boolean isEmpty() { return this.entryList.isEmpty(); }
 	
 	public DhSectionPos getPos() { return this.pos; }
 	

core/src/main/java/com/seibel/distanthorizons/core/dataObjects/fullData/sources/FullDataSourceV2.java

@@ -223,6 +223,13 @@ public class FullDataSourceV2 implements IDataSource<IDhLevel>
 	public boolean update(@NotNull FullDataSourceV2 inputDataSource, @Nullable IDhLevel level) { return this.update(inputDataSource); }
 	public boolean update(@NotNull FullDataSourceV2 inputDataSource)
 	{
+		// don't try updating if the input is empty
+		if (inputDataSource.mapping.isEmpty())
+		{
+			return false;
+		}
+		
+		
 		byte thisDetailLevel = this.pos.getDetailLevel();
 		byte inputDetailLevel = inputDataSource.pos.getDetailLevel();