diff --git a/OpenRa.Game/Clock.cs b/OpenRa.Game/Clock.cs
new file mode 100644
index 0000000000..10ea5ce435
--- /dev/null
+++ b/OpenRa.Game/Clock.cs
@@ -0,0 +1,109 @@
+namespace OpenRa.Game
+{
+	/// <summary>
+	/// Provides access to the current time, frame time, and frame rate.
+	/// </summary>
+	public static class Clock
+	{
+		/// <summary>
+		/// Performs one-time initialization for the clock service
+		/// </summary>
+		static Clock()
+		{
+			startTime = System.Environment.TickCount;
+			StartFrame();
+		}
+
+		public static void Reset()
+		{
+			frameCount = 0;
+			lastFrameCount = 0;
+			lastFrameRate = 0;
+			startTime = System.Environment.TickCount;
+			StartFrame();
+		}
+
+		#region StartFrame
+
+		/// <summary>
+		/// Indicates to the clock that a new frame has begun. This should be called exactly once per frame.
+		/// </summary>
+		public static void StartFrame() 
+		{
+			int ticks = System.Environment.TickCount - startTime;
+			frameStartTime = ticks / 1000.0;
+
+			frameCount++;
+
+			if( Time > nextFrameRateUpdateTime )
+			{
+				// set next update time
+				nextFrameRateUpdateTime += (1.0 / FramerateUpdateFrequency);
+				// average between last and current frame, to make spikes less severe
+				const int OldFramerateWeight = 10;
+				const int NewFramerateWeight = 1;
+				int newFrameRate = (frameCount - lastFrameCount) * FramerateUpdateFrequency;
+				lastFrameRate = (lastFrameRate * OldFramerateWeight + NewFramerateWeight * newFrameRate) / (OldFramerateWeight + NewFramerateWeight );
+				lastFrameCount = frameCount;
+			}
+		}
+
+		#endregion
+
+		#region Private Implementation Details
+
+		// number of framerate updates per second
+		private const int FramerateUpdateFrequency = 10;
+		
+		// the time at which the application started
+		private static int startTime;
+		// the time at which this frame began
+		private static double frameStartTime;
+		// total number of frames rendered
+		private static int frameCount = 0;
+		// next time to update fps count
+		private static double nextFrameRateUpdateTime = 0;
+		// frame count at most recent fps calculation
+		private static int lastFrameCount = 0;
+		// most recently calculated fps
+		private static int lastFrameRate = 0;
+
+		#endregion
+
+		#region Properties
+
+		/// <summary>
+		/// The time the current frame started
+		/// </summary>
+		public static double Time 
+		{
+			get { return frameStartTime; }
+		}
+
+		/// <summary>
+		/// The number of frames rendered since the engine started
+		/// </summary>
+		public static int FrameCount
+		{
+			get { return frameCount; }
+		}
+
+		/// <summary>
+		/// The most recent frame-rate
+		/// </summary>
+		public static int FrameRate
+		{
+			get { return lastFrameRate; }
+		}
+
+		/// <summary>
+		/// The frame time corresponding to the most recent frame-rate
+		/// </summary>
+		public static double FrameTime
+		{
+			get { return 1.0 / lastFrameRate; }
+		}
+
+		#endregion
+	}
+}
diff --git a/OpenRa.Game/MainWindow.cs b/OpenRa.Game/MainWindow.cs
index c42c2866e6..0822b4f850 100644
--- a/OpenRa.Game/MainWindow.cs
+++ b/OpenRa.Game/MainWindow.cs
@@ -89,17 +89,17 @@ namespace OpenRa.Game
 			Dictionary<Sheet, List<ushort>> indexMap = new Dictionary<Sheet, List<ushort>>();
 			Vertex[] vertices = new Vertex[4 * 128 * 128];//map.Width * map.Height];
 
-			for( int i = 0; i < 128; i++ )
-				for (int j = 0; j < 128; j++)
+			for( int i = map.XOffset; i < map.XOffset+ map.Width; i++ )
+				for (int j = map.YOffset; j < map.YOffset + map.Height; j++)
 				{
 					SheetRectangle<Sheet> tile = tileMapping[map.MapTiles[i, j]];
 
 					ushort offset = (ushort)(4 * (i * 128 + j));
 
-					vertices[offset] = new Vertex(24 * i, 24 * j, 0, U(tile,0), V(tile,0));
-					vertices[offset + 1] = new Vertex(24 + 24 * i, 24 * j, 0, U(tile,1), V(tile,0));
-					vertices[offset + 2] = new Vertex(24 * i, 24 + 24 * j, 0, U(tile,0), V(tile,1));
-					vertices[offset + 3] = new Vertex(24 + 24 * i, 24 + 24 * j, 0, U(tile,1), V(tile,1));
+					vertices[offset] = new Vertex(24 * i, 24 * j, 0, U(tile, 0), V(tile, 0));
+					vertices[offset + 1] = new Vertex(24 + 24 * i, 24 * j, 0, U(tile, 1), V(tile, 0));
+					vertices[offset + 2] = new Vertex(24 * i, 24 + 24 * j, 0, U(tile, 0), V(tile, 1));
+					vertices[offset + 3] = new Vertex(24 + 24 * i, 24 + 24 * j, 0, U(tile, 1), V(tile, 1));
 
 					List<ushort> indexList;
 					if (!indexMap.TryGetValue(tile.sheet, out indexList))
@@ -149,6 +149,8 @@ namespace OpenRa.Game
 
 			spriteHelper = new SpriteHelper(device);
 			fontHelper = new FontHelper(device, "Tahoma", 10, false);
+
+			Clock.Reset();
 		}
 
 		internal void Run()
@@ -182,15 +184,16 @@ namespace OpenRa.Game
 				int dx = x1 - e.X;
 				int dy = y1 - e.Y;
 				scrollPos = oldPos;
-				scrollPos.X += (float)dx / 320.0f;
-				scrollPos.Y += (float)dy / 240.0f;
+				scrollPos.X += (float)dx / (ClientSize.Width / 2);
+				scrollPos.Y += (float)dy / (ClientSize.Height / 2);
 			}
 		}
 
 		void Frame()
 		{
+			Clock.StartFrame();
 			device.Begin();
-			device.Clear( Color.Red.ToArgb(), Surfaces.Color );
+			device.Clear( 0, Surfaces.Color );
 
 			vertexBuffer.Bind(0);
 
@@ -215,7 +218,7 @@ namespace OpenRa.Game
 			effect.End();
 
 			spriteHelper.Begin();
-			fontHelper.Draw(spriteHelper, "fps: 1337", 0, 0, Color.White.ToArgb());
+			fontHelper.Draw(spriteHelper, "fps: " + Clock.FrameRate, 0, 0, Color.White.ToArgb());
 			spriteHelper.End();
 
 			device.End();
diff --git a/OpenRa.Game/OpenRa.Game.csproj b/OpenRa.Game/OpenRa.Game.csproj
index 72ccc8e056..36794a7e63 100644
--- a/OpenRa.Game/OpenRa.Game.csproj
+++ b/OpenRa.Game/OpenRa.Game.csproj
@@ -39,6 +39,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Clock.cs" />
     <Compile Include="MainWindow.cs">
       <SubType>Form</SubType>
     </Compile>