diff --git a/vtm/src/org/oscim/map/Animator.java b/vtm/src/org/oscim/map/Animator.java
index ff9d3433..50ced660 100644
--- a/vtm/src/org/oscim/map/Animator.java
+++ b/vtm/src/org/oscim/map/Animator.java
@@ -112,7 +112,7 @@ public class Animator {
 		if (relative)
 			scale = mStartPos.scale * scale;
 
-		scale = clamp(scale, Viewport.MIN_SCALE, Viewport.MAX_SCALE);
+		scale = mMap.viewport().limitScale(scale);
 
 		mDeltaPos.set(longitudeToX(geoPoint.getLongitude()) - mStartPos.x,
 		              latitudeToY(geoPoint.getLatitude()) - mStartPos.y,
@@ -131,15 +131,13 @@ public class Animator {
 
 		mMap.getMapPosition(mStartPos);
 
-		pos.scale = clamp(pos.scale,
-		                  Viewport.MIN_SCALE,
-		                  Viewport.MAX_SCALE);
+		pos.scale = mMap.viewport().limitScale(pos.scale);
 
 		mDeltaPos.set(pos.x - mStartPos.x,
 		              pos.y - mStartPos.y,
 		              pos.scale - mStartPos.scale,
 		              pos.bearing - mStartPos.bearing,
-		              clamp(pos.tilt, 0, Viewport.MAX_TILT) - mStartPos.tilt);
+		              mMap.viewport().limitTilt(pos.tilt) - mStartPos.tilt);
 
 		animStart(duration, ANIM_MOVE | ANIM_SCALE | ANIM_ROTATE | ANIM_TILT);
 	}
@@ -156,7 +154,7 @@ public class Animator {
 			scaleBy = mCurPos.scale * scaleBy;
 
 		mStartPos.copy(mCurPos);
-		scaleBy = clamp(scaleBy, Viewport.MIN_SCALE, Viewport.MAX_SCALE);
+		scaleBy = mMap.viewport().limitScale(scaleBy);
 
 		mDeltaPos.scale = scaleBy - mStartPos.scale;
 
diff --git a/vtm/src/org/oscim/map/ViewController.java b/vtm/src/org/oscim/map/ViewController.java
index 8237142b..3494f74a 100644
--- a/vtm/src/org/oscim/map/ViewController.java
+++ b/vtm/src/org/oscim/map/ViewController.java
@@ -124,7 +124,7 @@ public class ViewController extends Viewport {
 
 		double newScale = mPos.scale * scale;
 
-		newScale = FastMath.clamp(newScale, MIN_SCALE, MAX_SCALE);
+		newScale = clamp(newScale, mMinScale, mMaxScale);
 
 		if (newScale == mPos.scale)
 			return false;
@@ -175,21 +175,21 @@ public class ViewController extends Viewport {
 			degree += 360;
 
 		mPos.bearing = (float) degree;
+
 		updateMatrices();
 	}
 
 	public boolean tiltMap(float move) {
-		ThreadUtils.assertMainThread();
-
 		return setTilt(mPos.tilt + move);
 	}
 
 	public boolean setTilt(float tilt) {
 		ThreadUtils.assertMainThread();
 
-		tilt = FastMath.clamp(tilt, 0, MAX_TILT);
+		tilt = limitTilt(tilt);
 		if (tilt == mPos.tilt)
 			return false;
+
 		mPos.tilt = tilt;
 		updateMatrices();
 		return true;
@@ -198,11 +198,15 @@ public class ViewController extends Viewport {
 	public void setMapPosition(MapPosition mapPosition) {
 		ThreadUtils.assertMainThread();
 
-		mPos.scale = clamp(mapPosition.scale, MIN_SCALE, MAX_SCALE);
-		mPos.x = mapPosition.x;
-		mPos.y = mapPosition.y;
-		mPos.tilt = clamp(mapPosition.tilt, 0, MAX_TILT);
-		mPos.bearing = mapPosition.bearing;
+		mPos.copy(mapPosition);
+		limitPosition(mPos);
+
+		//	mPos.scale = clamp(mapPosition.scale, mMinScale, mMaxScale);
+		//	mPos.x = mapPosition.x;
+		//	mPos.y = mapPosition.y;
+		//	mPos.tilt = limitTilt(mapPosition.tilt);
+		//	mPos.bearing = mapPosition.bearing;
+
 		updateMatrices();
 	}
 
diff --git a/vtm/src/org/oscim/map/Viewport.java b/vtm/src/org/oscim/map/Viewport.java
index 21bcad86..9be3822f 100644
--- a/vtm/src/org/oscim/map/Viewport.java
+++ b/vtm/src/org/oscim/map/Viewport.java
@@ -36,13 +36,24 @@ import org.oscim.utils.FastMath;
 public class Viewport {
 	//static final Logger log = LoggerFactory.getLogger(Viewport.class);
 
-	public final static int MAX_ZOOMLEVEL = 20;
-	public final static int MIN_ZOOMLEVEL = 2;
+	private final static int MAX_ZOOMLEVEL = 20;
+	private final static int MIN_ZOOMLEVEL = 2;
+	private final static float MIN_TILT = 0;
+	private final static float MAX_TILT = 65;
 
-	public final static double MAX_SCALE = (1 << MAX_ZOOMLEVEL);
-	public final static double MIN_SCALE = (1 << MIN_ZOOMLEVEL);
+	protected double mMaxScale = (1 << MAX_ZOOMLEVEL);
+	protected double mMinScale = (1 << MIN_ZOOMLEVEL);
 
-	public final static float MAX_TILT = 65;
+	protected float mMinTilt = MIN_TILT;
+	protected float mMaxTilt = MAX_TILT;
+
+	protected float mMinBearing = -180;
+	protected float mMaxBearing = 180;
+
+	protected double mMinX = 0;
+	protected double mMaxX = 1;
+	protected double mMinY = 0;
+	protected double mMaxY = 1;
 
 	protected final MapPosition mPos = new MapPosition();
 
@@ -72,13 +83,76 @@ public class Viewport {
 	public final static float VIEW_SCALE = (VIEW_NEAR / VIEW_DISTANCE) * 0.5f;
 
 	public Viewport() {
-		mPos.scale = MIN_SCALE;
+		mPos.scale = mMinScale;
 		mPos.x = 0.5;
 		mPos.y = 0.5;
 		mPos.bearing = 0;
 		mPos.tilt = 0;
 	}
 
+	public double limitScale(double scale) {
+		if (scale > mMaxScale)
+			return mMaxScale;
+		else if (scale < mMinScale)
+			return mMinScale;
+
+		return scale;
+	}
+
+	public float limitTilt(float tilt) {
+		if (tilt > mMaxTilt)
+			return mMaxTilt;
+		else if (tilt < mMinTilt)
+			return mMinTilt;
+
+		return tilt;
+	}
+
+	public boolean limitPosition(MapPosition pos) {
+		boolean changed = false;
+		if (pos.scale > mMaxScale) {
+			pos.scale = mMaxScale;
+			changed = true;
+		} else if (pos.scale < mMinScale) {
+			pos.scale = mMinScale;
+			changed = true;
+		}
+
+		if (pos.tilt > mMaxTilt) {
+			pos.tilt = mMaxTilt;
+			changed = true;
+		} else if (pos.tilt < mMinTilt) {
+			pos.tilt = mMinTilt;
+			changed = true;
+		}
+
+		if (pos.bearing > mMaxBearing) {
+			pos.bearing = mMaxBearing;
+			changed = true;
+		} else if (pos.bearing < mMinBearing) {
+			pos.bearing = mMinBearing;
+			changed = true;
+		}
+
+		if (pos.x > mMaxX) {
+			pos.x = mMaxX;
+			changed = true;
+		} else if (pos.x < mMinX) {
+			pos.x = mMinX;
+			changed = true;
+		}
+
+		if (pos.y > mMaxY) {
+			pos.y = mMaxY;
+			changed = true;
+		} else if (pos.y < mMinY) {
+			pos.y = mMinY;
+			changed = true;
+		}
+
+		return changed;
+	}
+
 	/**
 	 * Get the current MapPosition.
 	 *