Hooks for garbage-collectable OpenGL resources.

the [...]GLNative classes now use GLContext instead of the platform-specific [...]GLContext implementations.
Updated the IGLContext interface with functions to query the current context.

Source/Examples/Tests/MathSpeed.cs

@@ -12,7 +12,7 @@ using OpenTK.Math;
 
 namespace Examples.Tests
 {
-    [Example("Math speed test", ExampleCategory.Test, 2, false)]
+    [Example("Math speed test", ExampleCategory.Test, 2/*, false*/)]
     public class MathSpeed
     {
         public static void Main()
@@ -31,7 +31,7 @@ namespace Examples.Tests
             Vector3.Add(ref a, ref b, out res);
             res = a + b;
             res = Vector3.Zero;
-
+            /*
             watch.Reset();
             watch.Start();
             for (int i = 100000000; --i != 0; )
@@ -63,6 +63,29 @@ namespace Examples.Tests
             watch.Stop();
             res += res;         // To make sure the whole for-loop isn't optimized-out
             Trace.WriteLine(String.Format("Vector3.Add(ref a, ref b, out res)\t{0}ns", (watch.Elapsed.TotalSeconds / 10.0).ToString()));
+*/
+            a = Vector3.UnitX;
+            b = Vector3.UnitY;
+            res = Vector3.Add(ref a, ref b);
+            Trace.WriteLine(res.ToString());
+
+            a = Vector3.UnitX;
+            b = Vector3.UnitY;
+            Vector3.Add(a, b, out res);
+            Trace.WriteLine(res.ToString());
+
+            Vector2Im q = new Vector2(0.0f, 1.0f);
+            Vector2Im p = new Vector2(2.0f, 3.0f);
+            Vector2Im s = Vector2.Add(p, q);
+            p = s + q;
+        }
+
+        static Vector3 pos = new Vector3();
+
+        static Vector3 Pos
+        {
+            get { return pos; }
+            set { pos = value; }
         }
     }
 }

Source/Examples/Tutorial/Text.cs

@@ -120,6 +120,9 @@ namespace Examples.Tutorial
             else if (scroll_speed < 0.0f && current_position < warparound_position)
                 current_position = initial_position;
 
+            TextHandle t = null;
+            text.Prepare((1.0 / e.Time).ToString(), serif, out t);
+
             // TextPrinter.Begin() sets up a 2d orthographic projection, with the x axis
             // moving from 0 to viewport.Width (left to right) and the y axis from
             // 0 to viewport.Height (top to bottom). This is the typical coordinate system
@@ -127,6 +130,13 @@ namespace Examples.Tutorial
             // TextPrinter.End() restores your previous projection/modelview matrices.
             text.Begin();
 
+            using (t)
+            {
+                //text.Begin();
+                text.Draw(t);
+                //text.End();
+            }
+
             GL.Translate(0.0f, current_position, 0.0f);
             text.Draw(poem_handle);
 

Source/OpenTK/GLContext.cs

@@ -17,10 +17,16 @@ namespace OpenTK
     /// </summary>
     public class GLContext : IGLContext
     {
-        /// <summary>
+        IGLContext implementation;  // The actual render context implementation for the underlying platform.
-        /// The actual render context implementation for the underlying platform.
+        List<IDisposable> dispose_queue = new List<IDisposable>();
-        /// </summary>
+        
-        private IGLContext implementation;
+        static SortedList<long, WeakReference> available_contexts =
+            new SortedList<long, WeakReference>();   // Contains all available OpenGL contexts.
+
+        delegate IntPtr GetCurrentContextDelegate();
+        static GetCurrentContextDelegate StaticGetCurrentContext;
+
+        #region public GLContext(DisplayMode mode, IWindowInfo window)
 
         /// <summary>
         /// Constructs a new GLContext with the specified DisplayMode, and bound to the specified IWindowInfo.
@@ -29,6 +35,9 @@ namespace OpenTK
         /// <param name="window"></param>
         public GLContext(DisplayMode mode, IWindowInfo window)
         {
+            if (available_contexts.Count == 0)
+                available_contexts.Add(0, new WeakReference(null));
+
             switch (Environment.OSVersion.Platform)
             {
                 case PlatformID.Unix:
@@ -48,6 +57,17 @@ namespace OpenTK
             }
         }
 
+        #endregion
+
+        #region public static IGLContext CurrentContext
+
+        public static GLContext CurrentContext
+        {
+            get { return (GLContext)available_contexts[StaticGetCurrentContext().ToInt64()].Target; }
+        }
+
+        #endregion
+
         #region --- IGLContext Members ---
 
         /// <summary>
@@ -79,7 +99,7 @@ namespace OpenTK
         /// </summary>
         public void CreateContext()
         {
-            implementation.CreateContext();
+            CreateContext(true, null);
         }
 
         /// <summary>
@@ -99,7 +119,7 @@ namespace OpenTK
         /// </remarks>
         public void CreateContext(bool direct)
         {
-            implementation.CreateContext(direct);
+            CreateContext(direct, null);
         }
 
         /// <summary>
@@ -112,6 +132,10 @@ namespace OpenTK
         public void CreateContext(bool direct, IGLContext source)
         {
             implementation.CreateContext(direct, source);
+
+            available_contexts.Add(Context.ToInt64(), new WeakReference(this));
+            if (StaticGetCurrentContext == null)
+                StaticGetCurrentContext = implementation.GetCurrentContext;
         }
 
         /// <summary>
@@ -130,6 +154,33 @@ namespace OpenTK
             implementation.MakeCurrent();
         }
 
+        /// <summary>
+        /// Gets a System.Boolean indicating whether this Context is current in the calling thread.
+        /// </summary>
+        public bool IsCurrent
+        {
+            get { return implementation.IsCurrent; }
+        }
+
+        /// <summary>
+        /// Gets a System.IntPtr containing the handle to the OpenGL context which is current in the
+        /// calling thread, or IntPtr.Zero if no OpenGL context is current.
+        /// </summary>
+        /// <returns>A System.IntPtr that holds the handle to the current OpenGL context.</returns>
+        public IntPtr GetCurrentContext()
+        {
+            return implementation.GetCurrentContext();
+        }
+
+        /// <summary>
+        /// Raised when a Context is destroyed.
+        /// </summary>
+        public event DestroyEvent<IGLContext> Destroy
+        {
+            add { implementation.Destroy += value; }
+            remove { implementation.Destroy -= value; }
+        }
+
         /// <summary>
         /// Gets the address of an OpenGL extension function.
         /// </summary>
@@ -162,6 +213,28 @@ namespace OpenTK
             set { implementation.VSync = value;  }
         }
 
+        /// <summary>
+        /// Registers an OpenGL resource for disposal.
+        /// </summary>
+        /// <param name="resource">The OpenGL resource to dispose.</param>
+        public void RegisterForDisposal(IDisposable resource)
+        {
+            GC.KeepAlive(resource);
+            dispose_queue.Add(resource);
+        }
+
+        /// <summary>
+        /// Disposes all registered OpenGL resources.
+        /// </summary>
+        public void DisposeResources()
+        {
+            foreach (IDisposable resource in dispose_queue)
+            {
+                resource.Dispose();
+            }
+            dispose_queue.Clear();
+        }
+
         #endregion
 
         #region IDisposable Members
@@ -171,6 +244,7 @@ namespace OpenTK
         /// </summary>
         public void Dispose()
         {
+            available_contexts.Remove(Context.ToInt64());
             implementation.Dispose();
         }
 

Source/OpenTK/GLControl.cs

@@ -200,7 +200,7 @@ namespace OpenTK
                 // specific depth for the DisplayMode - we let the driver select one instead.
                 display_mode.Color = new ColorMode(0);
                 context = new GLContext(display_mode, info);
-                context.CreateContext();
+                context.CreateContext(true, null);
                 idle = new PlatformIdle(info);
             }
             else

Source/OpenTK/GameWindow.cs

@@ -71,6 +71,8 @@ namespace OpenTK
 
         //InputDriver input_driver;
 
+        GLContext glContext;
+
         #endregion
 
         #region --- Internal Properties ---
@@ -126,6 +128,9 @@ namespace OpenTK
             glWindow.Destroy += new DestroyEvent(glWindow_Destroy);
             
             CreateWindow(mode, title);
+
+            glContext = new GLContext(mode, glWindow.WindowInfo);
+            glContext.CreateContext();
             //this.vsync = VSyncMode.Adaptive;
             this.VSync = VSyncMode.On;
         }
@@ -199,7 +204,8 @@ namespace OpenTK
 				    mode = new DisplayMode(640, 480);
 				    this.CreateWindow(mode);
 				}
-				return glWindow.Context;
+				//return glWindow.Context;
+                return glContext;
 			}
         }
 
@@ -354,24 +360,13 @@ namespace OpenTK
         private void CreateWindow(DisplayMode mode, string title)
         {
             if (!Exists)
-            {
-                try
             {
                 glWindow.CreateWindow(mode);
                 this.Title = title;
-                    //input_driver = new InputDriver(this);
-                }
-                catch (ApplicationException expt)
-                {
-                    Debug.Print(expt.ToString());
-                    throw;
-                }
             }
             else
-            {
                 throw new InvalidOperationException("A render window already exists for this GameWindow.");
         }
-        }
 
         #endregion
 

Source/OpenTK/Platform/DummyGLContext.cs

@@ -12,6 +12,7 @@ namespace OpenTK.Platform
 {
     /// <summary>
     /// An empty IGLContext implementation to be used inside the Visual Studio designer.
+    /// This class supports OpenTK, and is not intended for use by OpenTK programs.
     /// </summary>
     internal sealed class DummyGLContext : IGLContext
     {
@@ -37,6 +38,20 @@ namespace OpenTK.Platform
 
         public void SwapBuffers() { }
         public void MakeCurrent() { }
+        public bool IsCurrent { get { return true; } }
+        public IntPtr GetCurrentContext() { return IntPtr.Zero; }
+
+        public event DestroyEvent<IGLContext> Destroy;
+
+        public void RegisterForDisposal(IDisposable resource)
+        {
+            throw new NotImplementedException("Use the general GLContext class instead.");
+        }
+
+        public void DisposeResources()
+        {
+            throw new NotImplementedException("Use the general GLContext class instead.");
+        }
 
         public IntPtr GetAddress(string function) { return IntPtr.Zero; }
         public IEnumerable<DisplayMode> GetDisplayModes() { return null; }

Source/OpenTK/Platform/IGLContext.cs

@@ -30,28 +30,6 @@ namespace OpenTK.Platform
         /// </summary>
         DisplayMode Mode { get; }
 
-        /// <summary>
-        /// Creates an OpenGL context.
-        /// </summary>
-        void CreateContext();
-
-        /// <summary>
-        /// Creates an OpenGL context with a direct or indirect rendering mode. This parameter is ignored
-        /// on Windows platforms (direct mode only).
-        /// </summary>
-        /// <param name="direct">Set to true for direct rendering or false otherwise.</param>
-        /// <remarks>
-        /// <para>
-        /// Direct rendering is the default rendering mode for OpenTK, since it can provide higher performance
-        /// in some circumastances.
-        /// </para>
-        /// <para>
-        /// The 'direct' parameter is a hint, and will ignored if the specified mode is not supported (e.g. setting
-        /// indirect rendering on Windows platforms).
-        /// </para>
-        /// </remarks>
-        void CreateContext(bool direct);
-
         /// <summary>
         /// Creates an OpenGL context with the specified direct/indirect rendering mode and sharing state with the
         /// specified IGLContext.
@@ -71,6 +49,23 @@ namespace OpenTK.Platform
         /// </summary>
         void MakeCurrent();
 
+        /// <summary>
+        /// Gets a System.Boolean indicating whether this Context is current in the calling thread.
+        /// </summary>
+        bool IsCurrent { get; }
+
+        /// <summary>
+        /// Gets a System.IntPtr containing the handle to the OpenGL context which is current in the
+        /// calling thread, or IntPtr.Zero if no OpenGL context is current.
+        /// </summary>
+        /// <returns>A System.IntPtr that holds the handle to the current OpenGL context.</returns>
+        IntPtr GetCurrentContext();
+
+        /// <summary>
+        /// Raised when a Context is destroyed.
+        /// </summary>
+        event DestroyEvent<IGLContext> Destroy;
+
         /// <summary>
         /// Gets the address of an OpenGL extension function.
         /// </summary>
@@ -92,5 +87,24 @@ namespace OpenTK.Platform
         /// Gets or sets a value indicating whether VSyncing is enabled.
         /// </summary>
         bool VSync { get; set; }
+
+        /// <summary>
+        /// Registers an OpenGL resource for disposal.
+        /// </summary>
+        /// <param name="resource">The OpenGL resource to dispose.</param>
+        /// <remarks>
+        /// You may not destroy OpenGL resources in finalizers, since they run in
+        /// a different thread. To avoid this problem, use this method to register
+        /// a resource for disposal during the finalizer call, and call DisposeResources()
+        /// from the main thread to dispose it.
+        /// </remarks>
+        void RegisterForDisposal(IDisposable resource);
+
+        /// <summary>
+        /// Disposes all registered OpenGL resources.
+        /// </summary>
+        void DisposeResources();
     }
+
+    public delegate void DestroyEvent<T>(T sender, EventArgs e);
 }

Source/OpenTK/Platform/INativeGLWindow.cs

@@ -27,7 +27,7 @@ namespace OpenTK.Platform
         string Title { get; set; }
         bool Visible { get; set; }
         bool IsIdle { get; }
-        IGLContext Context { get; }
+        //IGLContext Context { get; }
         IInputDriver InputDriver { get; }
 
         event CreateEvent Create;

Source/OpenTK/Platform/Windows/WinGLContext.cs

@@ -23,7 +23,7 @@ namespace OpenTK.Platform.Windows
     /// Provides methods to create and control an opengl context on the Windows platform.
     /// This class supports OpenTK, and is not intended for use by OpenTK programs.
     /// </summary>
-    internal sealed class WinGLContext : OpenTK.Platform.IGLContext, IDisposable
+    internal sealed class WinGLContext : IGLContext
     {
         private IntPtr deviceContext;
         private IntPtr renderContext;
@@ -212,14 +212,11 @@ namespace OpenTK.Platform.Windows
             // Do not rely on OpenTK.Platform.Windows.Wgl - the context is not ready yet,
             // and Wgl extensions will fail to load.
             renderContext = Wgl.Imports.CreateContext(deviceContext);
-            if (renderContext != IntPtr.Zero)
+            if (renderContext == IntPtr.Zero)
-            {
-                Debug.WriteLine(String.Format("done! (id: {0})", renderContext));
-            }
-            else
-            {
                 throw new ApplicationException("Could not create OpenGL render context (Wgl.CreateContext() return 0).");
-            }
+            
+            Debug.WriteLine(String.Format("done! (id: {0})", renderContext));
+
             Wgl.Imports.MakeCurrent(deviceContext, renderContext);
             Wgl.LoadAll();
             GL.LoadAll();
@@ -267,6 +264,36 @@ namespace OpenTK.Platform.Windows
 
 	    #endregion
 
+        #region public bool IsCurrent
+
+        public bool IsCurrent
+        {
+            get { return Wgl.GetCurrentContext() == this.renderContext; }
+        }
+
+        #endregion
+
+        #region public IntPtr GetCurrentContext()
+
+        public IntPtr GetCurrentContext()
+        {
+            return Wgl.GetCurrentContext();
+        }
+
+        #endregion
+
+        public event DestroyEvent<IGLContext> Destroy;
+
+        public void RegisterForDisposal(IDisposable resource)
+        {
+            throw new NotImplementedException("Use the general GLContext class instead.");
+        }
+
+        public void DisposeResources()
+        {
+            throw new NotImplementedException("Use the general GLContext class instead.");
+        }
+
         #region public DisplayMode[] GetDisplayModes()
 
         public IEnumerable<DisplayMode> GetDisplayModes()
@@ -337,7 +364,6 @@ namespace OpenTK.Platform.Windows
 
         public void Dispose()
         {
-            //Debug.Print("Manually disposing WinGLContext {0}.", this.renderContext);
             Dispose(true);
             GC.SuppressFinalize(this);
         }
@@ -346,9 +372,7 @@ namespace OpenTK.Platform.Windows
         {
             if (!disposed)
             {
-                // Clean unmanaged resources here
+                DestroyContext();
-                // The following call uses the Debug and Wgl classes, making it unsafe?
-                ReleaseResources();
 
                 if (calledManually)
                 {
@@ -363,10 +387,13 @@ namespace OpenTK.Platform.Windows
             Dispose(false);
         }
 
-        #region private void ReleaseResources()
+        #region private void DestroyContext()
 
-        private void ReleaseResources()
+        private void DestroyContext()
         {
+            if (Destroy != null)
+                Destroy(this, EventArgs.Empty);
+
             if (renderContext != IntPtr.Zero)
             {
                 Wgl.Imports.MakeCurrent(IntPtr.Zero, IntPtr.Zero);
@@ -387,6 +414,7 @@ namespace OpenTK.Platform.Windows
                 }
             }
 
+            /*
             if (opengl32Handle != IntPtr.Zero)
             {
                 if (!Functions.FreeLibrary(opengl32Handle))
@@ -396,6 +424,7 @@ namespace OpenTK.Platform.Windows
                 }
                 opengl32Handle = IntPtr.Zero;
             }
+            */
         }
 
         #endregion

Source/OpenTK/Platform/Windows/WinGLNative.cs

@@ -27,7 +27,6 @@ namespace OpenTK.Platform.Windows
     {
         #region --- Fields ---
 
-        private WinGLContext glContext;
         private DisplayMode mode = new DisplayMode();
         private WinRawInput driver;
 
@@ -190,15 +189,6 @@ namespace OpenTK.Platform.Windows
 
         #endregion
 
-        #region public IGLContext Context
-
-        public IGLContext Context
-        {
-            get { return glContext; }
-        }
-
-        #endregion
-
         #region public bool Fullscreen
 
         public bool Fullscreen
@@ -286,7 +276,7 @@ namespace OpenTK.Platform.Windows
 
         #endregion
 
-        #region private void CreateWindow(DisplayMode mode)
+        #region public void CreateWindow(DisplayMode mode)
 
         public void CreateWindow(DisplayMode windowMode)
         {
@@ -331,17 +321,14 @@ namespace OpenTK.Platform.Windows
             // which is raised CreateHandle()
             CreateHandle(cp);
 
-            if (this.Handle != IntPtr.Zero && glContext != null)
+            if (this.Handle != IntPtr.Zero)
             {
                 Debug.WriteLine("Window creation was succesful.");
                 exists = true;
             }
-            else
+            else throw new ApplicationException(String.Format(
-            {
+                    "Could not create native window and/or context. Handle: {0}",
-                throw new ApplicationException(String.Format(
+                    this.Handle));
-                    "Could not create native window and/or context. Handle: {0}, Context {1}",
-                    this.Handle, this.Context.ToString()));
-            }
 
             Debug.Unindent();
         }
@@ -359,17 +346,6 @@ namespace OpenTK.Platform.Windows
 
             Debug.Print("Window created: {0}", window);
 
-            try
-            {
-                glContext = new WinGLContext(this.mode, this.WindowInfo);
-                glContext.CreateContext();
-            }
-            catch (ApplicationException expt)
-            {
-                Debug.Print("Could not create opengl context, error: {0}", expt.ToString());
-                throw;
-            }
-
             if (this.Create != null)
                 this.Create(this, e);
         }
@@ -510,7 +486,6 @@ namespace OpenTK.Platform.Windows
                 if (calledManually)
                 {
                     // Safe to clean managed resources
-                    glContext.Dispose();
                     //base.DestroyHandle();
                 }
                 disposed = true;

Source/OpenTK/Platform/X11/X11GLContext.cs

@@ -18,7 +18,7 @@ namespace OpenTK.Platform.X11
     /// Provides methods to create and control an opengl context on the X11 platform.
     /// This class supports OpenTK, and is not intended for use by OpenTK programs.
     /// </summary>
-    internal sealed class X11GLContext : OpenTK.Platform.IGLContext
+    internal sealed class X11GLContext : IGLContext
     {
         private IntPtr context;
         private DisplayMode mode;
@@ -235,11 +235,20 @@ namespace OpenTK.Platform.X11
 
         #endregion
 
-        public bool IsCurrent()
+        public bool IsCurrent
         {
+            //return GetCurrentContext() == context;
+            get { throw new NotImplementedException(); }
+        }
+
+        public IntPtr GetCurrentContext()
+        {
+            //return Glx.GetCurrentContext();
             throw new NotImplementedException();
         }
 
+        public event DestroyEvent<IGLContext> Destroy;
+
         #region public IntPtr GetAddress(string function)
 
         public IntPtr GetAddress(string function)
@@ -249,6 +258,16 @@ namespace OpenTK.Platform.X11
 
         #endregion
 
+        public void RegisterForDisposal(IDisposable resource)
+        {
+            throw new NotImplementedException("Use the general GLContext class instead.");
+        }
+
+        public void DisposeResources()
+        {
+            throw new NotImplementedException("Use the general GLContext class instead.");
+        }
+
         public IEnumerable<DisplayMode> GetDisplayModes()
         {
             throw new Exception("The method or operation is not implemented.");

Source/OpenTK/Platform/X11/X11GLNative.cs

@@ -25,7 +25,6 @@ namespace OpenTK.Platform.X11
     {
         #region --- Fields ---
 
-        private X11GLContext glContext;
         private WindowInfo window = new WindowInfo();
         private DisplayMode mode = new DisplayMode();
         private X11Input driver;
@@ -66,9 +65,8 @@ namespace OpenTK.Platform.X11
             // Open the display to the X server, and obtain the screen and root window.
             window.Display = API.OpenDisplay(null); // null == default display
             if (window.Display == IntPtr.Zero)
-            {
                 throw new Exception("Could not open connection to X");
-            }
+
             window.Screen = API.DefaultScreen(window.Display);
             window.RootWindow = API.RootWindow(window.Display, window.Screen);
 
@@ -240,15 +238,6 @@ namespace OpenTK.Platform.X11
 
         #endregion
 
-        #region public IGLContext Context
-
-        public OpenTK.Platform.IGLContext Context
-        {
-            get { return glContext; }
-        }
-
-        #endregion
-
         #region public IntPtr Handle
 
         /// <summary>
@@ -361,17 +350,15 @@ namespace OpenTK.Platform.X11
         public void CreateWindow(DisplayMode mode)
         {
             if (exists)
-            {
                 throw new ApplicationException("Render window already exists!");
-            }
+
-            else
-            {
             Debug.Print("Creating GameWindow with mode: {0}", mode.ToString());
             Debug.Indent();
 
-                glContext = new X11GLContext(mode, window);
+            //glContext = new X11GLContext(mode, window);
             //glContext.PrepareContext(window);
-                window.VisualInfo = (glContext.Info as X11.WindowInfo).VisualInfo;
+            //window.VisualInfo = (glContext.Info as X11.WindowInfo).VisualInfo;
+            //window.VisualInfo = Marshal.PtrToStructure(Glx.ChooseVisual(window.Display, window.Screen, 
 
             // Create a window on this display using the visual above
             Debug.Write("Opening render window... ");
@@ -396,9 +383,7 @@ namespace OpenTK.Platform.X11
                 (int)CreateWindowArgs.InputOutput, window.VisualInfo.visual, (UIntPtr)mask, ref attributes);
 
             if (window.Handle == IntPtr.Zero)
-                {
                 throw new ApplicationException("XCreateWindow call failed (returned 0).");
-                }
 
             // Set the window hints
             XSizeHints hints = new XSizeHints();
@@ -427,9 +412,9 @@ namespace OpenTK.Platform.X11
 
             Debug.Print("done! (id: {0})", window.Handle);
 
-                (glContext.Info as X11.WindowInfo).Handle = window.Handle;
+            //(glContext.Info as X11.WindowInfo).Handle = window.Handle;
-                glContext.CreateContext(true, null);
+            //glContext.CreateContext(true, null);
-                glContext.MakeCurrent();
+            //glContext.MakeCurrent();
 
             API.MapRaised(window.Display, window.Handle);
             mapped = true;
@@ -443,7 +428,6 @@ namespace OpenTK.Platform.X11
             Debug.WriteLine("GameWindow creation completed successfully!");
             exists = true;
         }
-        }
 
         #endregion
 
@@ -612,8 +596,8 @@ namespace OpenTK.Platform.X11
             {
                 if (manuallyCalled)
                 {
-                    if (glContext != null)
+                    //if (glContext != null)
-                        glContext.Dispose();
+                    //    glContext.Dispose();
 
                     // Kills connection to the X-Server. We don't want that,
                     // 'cause it kills the ExampleLauncher too.