Added timing information to UpdateFrame.

Removed T02_Resizable_Window.cs and added T02_Vertex_Array_Cube.cs
Added Shapes/Cube.cs to Examples.

Source/Examples/Shapes/Cube.cs

@@ -0,0 +1,62 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+using OpenTK.Math;
+using System.Drawing;
+
+namespace Examples.Shapes
+{
+    public static class Cube
+    {
+        public static readonly Vector3[] Vertices = new Vector3[8]
+        {
+            new Vector3(-1.0f, -1.0f,  1.0f),
+            new Vector3( 1.0f, -1.0f,  1.0f),
+            new Vector3( 1.0f,  1.0f,  1.0f),
+            new Vector3(-1.0f,  1.0f,  1.0f),
+            new Vector3(-1.0f, -1.0f, -1.0f),
+            new Vector3( 1.0f, -1.0f, -1.0f), 
+            new Vector3( 1.0f,  1.0f, -1.0f),
+            new Vector3(-1.0f,  1.0f, -1.0f),
+        };
+
+        public static readonly ushort[] Indices =
+        {
+            // front face
+            0, 1, 2, 2, 3, 0,
+            // top face
+            3, 2, 6, 6, 7, 3,
+            // back face
+            7, 6, 5, 5, 4, 7,
+            // left face
+            4, 0, 3, 3, 7, 4,
+            // bottom face
+            0, 1, 5, 5, 4, 0,
+            // right face
+            1, 5, 6, 6, 2, 1,
+        };
+
+        public static readonly Vector3[] Normals =
+        {
+            new Vector3( 1.0f,  0.0f,  0.0f),
+            new Vector3( 0.0f,  1.0f,  0.0f),                
+            new Vector3( 0.0f,  0.0f,  1.0f),
+            new Vector3(-1.0f,  0.0f,  0.0f),
+            new Vector3( 0.0f, -1.0f,  0.0f),                
+            new Vector3( 0.0f,  0.0f, -1.0f),
+        };
+
+        public static readonly int[] Colors =
+        {
+            Color.Firebrick.ToArgb(),
+            Color.Honeydew.ToArgb(),
+            Color.Moccasin.ToArgb(),
+            Color.Yellow.ToArgb(),
+            Color.Crimson.ToArgb(),
+            Color.DarkGoldenrod.ToArgb(),
+            Color.ForestGreen.ToArgb(),
+            Color.Sienna.ToArgb(),
+        };
+    }
+}

Source/Examples/Tutorial/T01_Simple_Window.cs

@@ -22,6 +22,8 @@ namespace Examples.Tutorial
             this.CreateWindow(new DisplayMode(800, 600));
         }
 
+        #region OnResize
+
         /// <summary>
         /// Override the OnResize method to respond to window resize events.
         /// Do not forget to call base.OnResize() so that event listeners
@@ -39,6 +41,10 @@ namespace Examples.Tutorial
             base.OnResize(e);
         }
 
+        #endregion
+
+        #region OnRenderFrame
+
         /// <summary>
         /// Override the OnRenderFrame method to add your drawing code.
         /// Do not forget to call base.OnRenderFrame() so that event listeners
@@ -65,6 +71,8 @@ namespace Examples.Tutorial
             base.OnRenderFrame(e);
         }
 
+        #endregion
+
         #region IExample Members
 
         public void Launch()

Source/Examples/Tutorial/T02_Resizable_Window.cs

@@ -1,76 +0,0 @@
-#region --- License ---
-/* Copyright (c) 2006, 2007 Stefanos Apostolopoulos
- * See license.txt for license info
- */
-#endregion
-
-using System;
-using System.Collections.Generic;
-using System.Text;
-using System.Drawing;
-
-using OpenTK;
-using OpenTK.OpenGL;
-
-namespace Examples.Tutorial
-{
-    class T02_Resizable_Window : GameWindow, IExample
-    {
-        public T02_Resizable_Window()
-        {
-            this.CreateWindow(new DisplayMode(800, 600));
-        }
-
-        /// <summary>
-        /// Override the OnResize method to respond to window resize events.
-        /// Do not forget to call base.OnResize() so that event listeners
-        /// will be notified of window resize events!
-        /// </summary>
-        /// <param name="e"></param>
-        protected override void OnResize(OpenTK.Platform.ResizeEventArgs e)
-        {
-            GL.Viewport(0, 0, e.Width, e.Height);
-            
-            GL.MatrixMode(GL.Enums.MatrixMode.PROJECTION);
-            GL.LoadIdentity();
-            GL.Ortho(-1.0, 1.0, -1.0, 1.0, 0.0, 4.0);
-
-            base.OnResize(e);
-        }
-
-        /// <summary>
-        /// Override the OnRenderFrame method to add your drawing code.
-        /// Do not forget to call base.OnRenderFrame() so that event listeners
-        /// will be notified of frame rendering events!
-        /// </summary>
-        /// <param name="e">Not used.</param>
-        public override void OnRenderFrame(EventArgs e)
-        {
-            GL.Clear(GL.Enums.ClearBufferMask.COLOR_BUFFER_BIT);
-
-            GL.Begin(GL.Enums.BeginMode.TRIANGLES);
-
-            GL.Color3(Color.SpringGreen);
-            GL.Vertex2(-1.0f, 1.0f);
-            GL.Color3(Color.SteelBlue);
-            GL.Vertex2(0.0f, -1.0f);
-            GL.Color3(Color.PeachPuff);
-            GL.Vertex2(1.0f, 1.0f);
-
-            GL.End();
-
-            Context.SwapBuffers();
-
-            base.OnRenderFrame(e);
-        }
-
-        #region IExample Members
-
-        public void Launch()
-        {
-            this.Run();
-        }
-
-        #endregion
-    }
-}

Source/Examples/Tutorial/T02_Vertex_Array_Cube.cs

@@ -0,0 +1,150 @@
+#region --- License ---
+/* Copyright (c) 2006, 2007 Stefanos Apostolopoulos
+ * See license.txt for license info
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Drawing;
+using System.Threading;
+
+using OpenTK;
+using OpenTK.OpenGL;
+
+namespace Examples.Tutorial
+{
+    class T02_Vertex_Array_Cube : GameWindow, IExample
+    {
+        float angle;
+
+        #region Constructor
+
+        public T02_Vertex_Array_Cube()
+        {
+            this.CreateWindow(new DisplayMode(800, 600));
+        }
+
+        #endregion
+
+        #region OnLoad
+
+        public override void OnLoad(EventArgs e)
+        {
+            base.OnLoad(e);
+
+            GL.ClearColor(Color.MidnightBlue);
+            GL.Enable(GL.Enums.EnableCap.DEPTH_TEST);
+            
+            GL.EnableClientState(GL.Enums.EnableCap.VERTEX_ARRAY);
+            GL.EnableClientState(GL.Enums.EnableCap.COLOR_ARRAY);
+            GL.VertexPointer(3, GL.Enums.VertexPointerType.FLOAT, 0, Shapes.Cube.Vertices);
+            GL.ColorPointer(4, GL.Enums.ColorPointerType.UNSIGNED_BYTE, 0, Shapes.Cube.Colors);
+        }
+
+        #endregion
+
+        #region OnResize
+
+        /// <summary>
+        /// Called when the user resizes the window.
+        /// </summary>
+        /// <param name="e">Contains the new width/height of the window.</param>
+        /// <remarks>
+        /// You want the OpenGL viewport to match the window. This is the place to do it!
+        /// </remarks>
+        protected override void OnResize(OpenTK.Platform.ResizeEventArgs e)
+        {
+            base.OnResize(e);
+
+            GL.Viewport(0, 0, Width, Height);
+
+            double ratio = e.Width / (double)e.Height;
+
+            GL.MatrixMode(GL.Enums.MatrixMode.PROJECTION);
+            GL.LoadIdentity();
+            Glu.Perspective(45.0, ratio, 1.0, 64.0);
+        }
+
+        #endregion
+
+        #region OnUpdateFrame
+
+        /// <summary>
+        /// Prepares the next frame for rendering.
+        /// </summary>
+        /// <remarks>
+        /// Place your control logic here. This is the place to respond to user input,
+        /// update object positions etc.
+        /// </remarks>
+        public override void OnUpdateFrame(UpdateFrameEventArgs e)
+        {
+            if (Keyboard[0][OpenTK.Input.Key.Escape])
+            {
+                this.Exit();
+                return;
+            }
+
+            if ((Keyboard[0][OpenTK.Input.Key.AltLeft] || Keyboard[0][OpenTK.Input.Key.AltRight]) &&
+                Keyboard[0][OpenTK.Input.Key.Enter])
+            {
+                Fullscreen = !Fullscreen;
+            }
+
+            GL.MatrixMode(GL.Enums.MatrixMode.MODELVIEW);
+            GL.LoadIdentity();
+            Glu.LookAt(
+                0.0, 5.0, 5.0,
+                0.0, 0.0, 0.0,
+                0.0, 1.0, 0.0
+            );
+
+            GL.Rotate(angle, 0.0f, 1.0f, 0.0f);
+            angle += 180.0f * e.Time;
+            if (angle > 720.0f)
+                angle -= 720.0f;
+        }
+
+        #endregion
+
+        #region OnRenderFrame
+
+        /// <summary>
+        /// Place your rendering code here.
+        /// </summary>
+        public override void OnRenderFrame(EventArgs e)
+        {
+            GL.Clear(GL.Enums.ClearBufferMask.COLOR_BUFFER_BIT | GL.Enums.ClearBufferMask.DEPTH_BUFFER_BIT);
+
+            unsafe
+            {
+                fixed (ushort* index_pointer = Shapes.Cube.Indices)
+                {
+                    GL.DrawElements(GL.Enums.BeginMode.TRIANGLES, Shapes.Cube.Indices.Length,
+                        GL.Enums.All.UNSIGNED_SHORT, index_pointer);
+                }
+            }
+
+            Context.SwapBuffers();
+            Thread.Sleep(0);
+        }
+
+        #endregion
+
+        #region public void Launch()
+
+        /// <summary>
+        /// Launches this example.
+        /// </summary>
+        /// <remarks>
+        /// Provides a simple way for the example launcher to launch the examples.
+        /// </remarks>
+        public void Launch()
+        {
+            Run();
+        }
+
+        #endregion
+    }
+}

Source/Examples/Tutorial/T03_Immediate_Mode_Cube.cs

@@ -46,7 +46,7 @@ namespace Examples.Tutorial
         {
             base.OnLoad(e);
 
-            GL.ClearColor(0.1f, 0.1f, 0.5f, 0.0f);
+            GL.ClearColor(Color.MidnightBlue);
             GL.Enable(GL.Enums.EnableCap.DEPTH_TEST);
         }
 
@@ -85,7 +85,7 @@ namespace Examples.Tutorial
         /// Place your control logic here. This is the place to respond to user input,
         /// update object positions etc.
         /// </remarks>
-        public override void OnUpdateFrame(EventArgs e)
+        public override void OnUpdateFrame(UpdateFrameEventArgs e)
         {
             if (Keyboard[0][OpenTK.Input.Key.Escape])
             {

Source/Examples/Tutorial/T07_Display_Lists_Flower.cs

@@ -123,7 +123,7 @@ namespace Examples.Tutorial
 
         #region OnUpdateFrame
 
-        public override void OnUpdateFrame(EventArgs e)
+        public override void OnUpdateFrame(UpdateFrameEventArgs e)
         {
             base.OnUpdateFrame(e);
 

Source/Examples/Tutorial/T08_VBO.cs

@@ -129,7 +129,7 @@ namespace Examples.Tutorial
         /// Place your control logic here. This is the place to respond to user input,
         /// update object positions etc.
         /// </remarks>
-        public override void OnUpdateFrame(EventArgs e)
+        public override void OnUpdateFrame(UpdateFrameEventArgs e)
         {
             if (Keyboard[0][OpenTK.Input.Key.Escape])
             {

Source/Examples/Tutorial/T10_GLSL_Cube.cs

@@ -148,7 +148,7 @@ namespace Examples.Tutorial
         /// Occurs when it is time to update the next frame.
         /// </summary>
         /// <param name="e">Not used yet.</param>
-        public override void OnUpdateFrame(EventArgs e)
+        public override void OnUpdateFrame(UpdateFrameEventArgs e)
         {
             base.OnUpdateFrame(e);
 

Source/Examples/WinForms/W03_Extensions.resx

@@ -0,0 +1,123 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <metadata name="backgroundWorker1.TrayLocation" type="System.Drawing.Point, System.Drawing, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a">
+    <value>17, 17</value>
+  </metadata>
+</root>

Source/OpenTK/GLControl.resx

@@ -0,0 +1,120 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+</root>

Source/OpenTK/GameWindow.cs

@@ -316,12 +316,19 @@ namespace OpenTK
 
             Debug.Print("Entering main loop");
 
+            System.Diagnostics.Stopwatch watch = new Stopwatch();
+            watch.Reset();
+            UpdateFrameEventArgs updateArgs = new UpdateFrameEventArgs();
+
             while (this.Exists && !IsExiting)
             {
                 this.ProcessEvents();
                 if (!IsExiting)
                 {
-                    this.OnUpdateFrame(EventArgs.Empty);
+                    updateArgs.Time = watch.ElapsedMilliseconds / 1000.0f;
+                    watch.Reset();
+                    watch.Start();
+                    this.OnUpdateFrame(updateArgs);
                     this.OnRenderFrame(EventArgs.Empty);
                 }
             }
@@ -388,7 +395,7 @@ namespace OpenTK
 
         #endregion
 
-        #region public virtual void OnUpdateFrame(EventArgs e)
+        #region public virtual void OnUpdateFrame(UpdateFrameEventArgs e)
 
         /// <summary>
         /// Raises the UpdateFrame event. Override in derived classes to update a frame.
@@ -397,7 +404,7 @@ namespace OpenTK
         /// If overriden, the base.OnUpdateFrame() function should be called, to ensure
         /// listeners are notified of UpdateFrame events.
         /// </remarks>
-        public virtual void OnUpdateFrame(EventArgs e)
+        public virtual void OnUpdateFrame(UpdateFrameEventArgs e)
         {
             if (!this.Exists && !this.IsExiting)
             {
@@ -616,4 +623,18 @@ namespace OpenTK
 
         #endregion
     }
+
+    public class UpdateFrameEventArgs : EventArgs
+    {
+        private float time;
+
+        /// <summary>
+        /// Gets the Time elapsed between frame updates, in seconds.
+        /// </summary>
+        public float Time
+        {
+            get { return time; }
+            internal set { time = value; }
+        }
+    }
 }

Source/OpenTK/Platform/IGameWindow.cs

@@ -15,7 +15,7 @@ namespace OpenTK.Platform
         void Run();
 
         void OnRenderFrame(EventArgs e);
-        void OnUpdateFrame(EventArgs e);
+        void OnUpdateFrame(UpdateFrameEventArgs e);
         void OnLoad(EventArgs e);
         void Exit();
 
@@ -27,7 +27,7 @@ namespace OpenTK.Platform
         IList<OpenTK.Input.Keyboard> Keyboard { get; }
     }
 
-    public delegate void UpdateFrameEvent(object sender, EventArgs e);
+    public delegate void UpdateFrameEvent(object sender, UpdateFrameEventArgs e);
     public delegate void RenderFrameEvent(object sender, EventArgs e);
     public delegate void LoadEvent(object sender, EventArgs e);
 }