diff --git a/vtm/src/org/oscim/layers/tile/BitmapTileLayer.java b/vtm/src/org/oscim/layers/tile/BitmapTileLayer.java
index e2cc974e..fcf113e6 100644
--- a/vtm/src/org/oscim/layers/tile/BitmapTileLayer.java
+++ b/vtm/src/org/oscim/layers/tile/BitmapTileLayer.java
@@ -30,7 +30,6 @@ import org.oscim.tiling.source.ITileDataSink;
 import org.oscim.tiling.source.ITileDataSource;
 import org.oscim.tiling.source.ITileDataSource.QueryResult;
 import org.oscim.tiling.source.TileSource;
-import org.oscim.tiling.source.bitmap.BitmapTileSource;
 import org.oscim.utils.FastMath;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -41,7 +40,7 @@ public class BitmapTileLayer extends TileLayer<TileLoader> {
 
 	private final static int CACHE_LIMIT = 50;
 
-	private final BitmapTileSource mTileSource;
+	protected final TileSource mTileSource;
 
 	public static class FadeStep {
 		public final double scaleStart, scaleEnd;
@@ -55,11 +54,11 @@ public class BitmapTileLayer extends TileLayer<TileLoader> {
 		}
 	}
 
-	public BitmapTileLayer(Map map, BitmapTileSource tileSource) {
+	public BitmapTileLayer(Map map, TileSource tileSource) {
 		this(map, tileSource, CACHE_LIMIT);
 	}
 
-	public BitmapTileLayer(Map map, BitmapTileSource tileSource, int cacheLimit) {
+	public BitmapTileLayer(Map map, TileSource tileSource, int cacheLimit) {
 		super(map, tileSource.getZoomLevelMin(), tileSource.getZoomLevelMax(), cacheLimit);
 		mTileSource = tileSource;
 		initLoader();
diff --git a/vtm/src/org/oscim/tiling/source/TileSource.java b/vtm/src/org/oscim/tiling/source/TileSource.java
index 67b5c85e..0a307260 100644
--- a/vtm/src/org/oscim/tiling/source/TileSource.java
+++ b/vtm/src/org/oscim/tiling/source/TileSource.java
@@ -18,8 +18,13 @@ package org.oscim.tiling.source;
 
 import java.util.HashMap;
 
+import org.oscim.layers.tile.BitmapTileLayer.FadeStep;
+
 public abstract class TileSource {
 
+	protected int mZoomMin;
+	protected int mZoomMax;
+
 	public abstract ITileDataSource getDataSource();
 
 	public abstract OpenResult open();
@@ -37,6 +42,18 @@ public abstract class TileSource {
 		tileCache = cache;
 	}
 
+	public int getZoomLevelMax() {
+		return mZoomMax;
+	}
+
+	public int getZoomLevelMin() {
+		return mZoomMin;
+	}
+
+	public FadeStep[] getFadeSteps() {
+		return null;
+	}
+
 	public TileSource setOption(String key, String value) {
 		options.put(key, value);
 		return this;
diff --git a/vtm/src/org/oscim/tiling/source/bitmap/BitmapTileSource.java b/vtm/src/org/oscim/tiling/source/bitmap/BitmapTileSource.java
index edaea7c2..a6c098ea 100644
--- a/vtm/src/org/oscim/tiling/source/bitmap/BitmapTileSource.java
+++ b/vtm/src/org/oscim/tiling/source/bitmap/BitmapTileSource.java
@@ -6,7 +6,6 @@ import java.io.InputStream;
 import org.oscim.backend.CanvasAdapter;
 import org.oscim.backend.canvas.Bitmap;
 import org.oscim.core.Tile;
-import org.oscim.layers.tile.BitmapTileLayer.FadeStep;
 import org.oscim.tiling.source.ITileDataSink;
 import org.oscim.tiling.source.ITileDataSource;
 import org.oscim.tiling.source.ITileDecoder;
@@ -19,8 +18,6 @@ import org.slf4j.LoggerFactory;
 public abstract class BitmapTileSource extends UrlTileSource {
 	static final Logger log = LoggerFactory.getLogger(LwHttp.class);
 
-	private final int mZoomMin;
-	private final int mZoomMax;
 	private final String mFileExtension;
 	private final String mMimeType;
 
@@ -41,18 +38,6 @@ public abstract class BitmapTileSource extends UrlTileSource {
 		mMimeType = mimeType;
 	}
 
-	public int getZoomLevelMax() {
-		return mZoomMax;
-	}
-
-	public int getZoomLevelMin() {
-		return mZoomMin;
-	}
-
-	public FadeStep[] getFadeSteps() {
-		return null;
-	}
-
 	public String getTileUrl(Tile tile) {
 		return null;
 	}