[Win] Added combined XInput+WinMM joystick driver

Joystick devices will be queried through XInput first, with a fallback
to WinMM in case they are not recognized by the newer API.

Source/OpenTK/OpenTK.csproj

@@ -167,6 +167,7 @@
     <Compile Include="Platform\Egl\EglWinContext.cs" />
     <Compile Include="Platform\MappedGamePadDriver.cs" />
     <Compile Include="Platform\Windows\WinInputBase.cs" />
+    <Compile Include="Platform\Windows\WinCombinedJoystick.cs" />
     <Compile Include="Platform\Windows\XInputJoystick.cs" />
     <Compile Include="Platform\X11\Bindings\DL.cs" />
     <Compile Include="Platform\X11\Bindings\INotify.cs" />

Source/OpenTK/Platform/Windows/WinCombinedJoystick.cs

@@ -0,0 +1,126 @@
+#region License
+//
+// XInputJoystick.cs
+//
+// Author:
+//       Stefanos A. <stapostol@gmail.com>
+//
+// Copyright (c) 2006-2013 Stefanos Apostolopoulos
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+using OpenTK.Input;
+using System.Runtime.InteropServices;
+using System.Security;
+using System.Diagnostics;
+
+namespace OpenTK.Platform.Windows
+{
+    /// \internal
+    /// <summary>
+    /// Combined XInput + WinMM joystick driver.
+    /// Devices with XInput drivers are accessed through XInput
+    /// Devices without XInput drivers are accessed through WinMM.
+    /// This ensures proper support for e.g. the XBox360 controller
+    /// triggers, which are not reported correctly on WinMM.
+    /// </summary>
+    class WinCombinedJoystick : IJoystickDriver2, IDisposable
+    {
+        readonly XInputJoystick xinput;
+        readonly WinMMJoystick winmm;
+
+        #region Constructors
+
+        public WinCombinedJoystick(XInputJoystick xinput, WinMMJoystick winmm)
+        {
+            if (xinput == null)
+                throw new ArgumentNullException("xinput");
+            if (winmm == null)
+                throw new ArgumentNullException("winmm");
+
+            this.xinput = xinput;
+            this.winmm = winmm;
+        }
+
+        #endregion
+
+        #region IJoystickDriver2 Members
+
+        public JoystickState GetState(int index)
+        {
+            JoystickState state = xinput.GetState(index);
+            if (!state.IsConnected)
+                state = winmm.GetState(index);
+            return state;
+        }
+
+        public JoystickCapabilities GetCapabilities(int index)
+        {
+            JoystickCapabilities state = xinput.GetCapabilities(index);
+            if (!state.IsConnected)
+                state = winmm.GetCapabilities(index);
+            return state;
+        }
+
+        public Guid GetGuid(int index)
+        {
+            Guid guid = xinput.GetGuid(index);
+            if (guid == Guid.Empty)
+                guid = winmm.GetGuid(index);
+            return guid;
+        }
+
+        #endregion
+
+        #region IDisposable Members
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        void Dispose(bool manual)
+        {
+            if (manual)
+            {
+                xinput.Dispose();
+                winmm.Dispose();
+            }
+            else
+            {
+                Debug.Print("{0} leaked, did you forget to call Dispose()?", typeof(XInputJoystick).Name);
+            }
+        }
+
+#if DEBUG
+        ~WinCombinedJoystick()
+        {
+            Dispose(false);
+        }
+#endif
+
+        #endregion
+    }
+}