diff --git a/mono/Assistance/MainWindow.cs b/mono/Assistance/MainWindow.cs
index 4c71d61..62aba73 100644
--- a/mono/Assistance/MainWindow.cs
+++ b/mono/Assistance/MainWindow.cs
@@ -98,7 +98,7 @@ namespace Assistance {
 
 		private void beginTrack(Gdk.Device device) {
 			endDragAndTrack();
-			track = new Track(device);
+			track = new Track(Track.getTouchId(), device);
 			ticksStart = Timer.ticks();
 		}
 
diff --git a/mono/Assistance/Tool.cs b/mono/Assistance/Tool.cs
index f592f3d..8c7e7fd 100644
--- a/mono/Assistance/Tool.cs
+++ b/mono/Assistance/Tool.cs
@@ -9,21 +9,21 @@ namespace Assistance {
 		Multiline = 4
 	};
 
-	public class Tool {
+	public class MotionHandler {
+		public bool paint_begin() { return false; }
+		public void paint_track_begin(Track track) { }
+		public void paint_track_point(Track track) { }
+		public void paint_track_end(Track track) { }
+		public bool paint_apply() { return false; }
+		public void paint_cancel() { }
+	}
+
+	public class Tool: MotionHandler {
 		public void activate() { }
 		
-		public int getAvailableStackSize()
-			{ return 1; }
-		public bool getIsCancellable()
-			{ return false; }
 		public Modifiers getAvailableModifiers()
 			{ return Modifiers.None; }
 		
-		public bool paint_begin(Track track) { return false; }
-		public void paint_point(TrackPoint point, Track track) { }
-		public bool paint_apply() { return false; }
-		public void paint_cancel() { }
-		
 		public void disactivate() { }
 	}
 }
diff --git a/mono/Assistance/Track.cs b/mono/Assistance/Track.cs
index 0454046..8e6cc0c 100644
--- a/mono/Assistance/Track.cs
+++ b/mono/Assistance/Track.cs
@@ -7,20 +7,26 @@ namespace Assistance {
 		public static readonly Pen pen = new Pen("Dark Green", 3.0);
 		public static readonly Pen penSpecial = new Pen("Blue", 3.0);
 		public static readonly Pen penPreview = new Pen("Dark Green", 1.0, 0.25);
-	
+
+		private static long lastTouchId;
+		
+		public long touchId;
 		public readonly Gdk.Device device;
 		public readonly List<TrackPoint> points = new List<TrackPoint>();
 
 		private readonly List<Track> parents = new List<Track>();
 		private readonly List<Geometry.TransformFunc> transformFuncs = new List<Geometry.TransformFunc>();
 
-		public Track(Gdk.Device device)
+		public static long getTouchId() { return ++lastTouchId; }
+
+		public Track(long touchId, Gdk.Device device)
 		{
+			this.touchId = touchId;
 			this.device = device;
 		}
 
 		public Track(Track parent, Geometry.TransformFunc transformFunc):
-			this(parent.device)
+			this(parent.touchId, parent.device)
 		{
 			parents.AddRange(parent.parents);
 			parents.Add(parent);