* Graphics/ES10/Helper.cs:

* Graphics/ES11/Helper.cs:
* Graphics/ES20/Helper.cs:
* Graphics/BindingsBase.cs:
* Platform/X11/GlxHelper.cs:
* Graphics/OpenGL/GLHelper.cs:
* Platform/X11/X11GLContext.cs: Modified BindingsBase to define
  abstract GetAddress method (reason: removes OpenTK.Graphics-specific
  code from BindingsBase and allows it to be used in different
  bindings).
Implemented GraphicsBindingsBase and modified the OpenGL and OpenGL|ES
  bindings to use this.
Modified the GLX bindings to inherit from BindingsBase (reason:
  reduces code duplication for extension loading).

Source/OpenTK/Graphics/BindingsBase.cs

@@ -32,10 +32,10 @@ using System.Reflection;
 using System.Runtime.InteropServices;
 using System.Diagnostics;
 
-namespace OpenTK.Graphics
+namespace OpenTK
 {
     /// <summary>
-    /// Provides a common foundation for all flat API classes.
+    /// Provides a common foundation for all flat API bindings and implements the extension loading interface.
     /// </summary>
     public abstract class BindingsBase
     {
@@ -70,13 +70,16 @@ namespace OpenTK.Graphics
             DelegatesClass = this.GetType().GetNestedType("Delegates", BindingFlags.Static | BindingFlags.NonPublic);
             CoreClass = this.GetType().GetNestedType("Core", BindingFlags.Static | BindingFlags.NonPublic);
 
+            if (CoreClass != null)
+            {
                 MethodInfo[] methods = CoreClass.GetMethods(BindingFlags.Static | BindingFlags.NonPublic);
-            CoreFunctionMap = new SortedList<string, MethodInfo>(methods.Length);
+                CoreFunctionMap = new SortedList<string, MethodInfo>(methods.Length); // Avoid resizing
                 foreach (MethodInfo m in methods)
                 {
                     CoreFunctionMap.Add(m.Name, m);
                 }
             }
+        }
 
         #endregion
 
@@ -91,6 +94,8 @@ namespace OpenTK.Graphics
             set { rebuildExtensionList = value; }
         }
 
+        protected abstract IntPtr GetAddress(string funcname);
+
         #endregion
 
         #region Internal Members
@@ -176,9 +181,9 @@ namespace OpenTK.Graphics
         #region GetExtensionDelegate
 
         // Creates a System.Delegate that can be used to call a dynamically exported OpenGL function.
-        internal static Delegate GetExtensionDelegate(string name, Type signature)
+        internal Delegate GetExtensionDelegate(string name, Type signature)
         {
-            IntPtr address = (GraphicsContext.CurrentContext as IGraphicsContextInternal).GetAddress(name);
+            IntPtr address = GetAddress(name);
             
             if (address == IntPtr.Zero ||
                 address == new IntPtr(1) ||     // Workaround for buggy nvidia drivers which return
@@ -197,3 +202,14 @@ namespace OpenTK.Graphics
         #endregion
     }
 }
+
+namespace OpenTK.Graphics
+{
+    public class GraphicsBindingsBase : BindingsBase
+    {
+        protected override IntPtr GetAddress(string funcname)
+        {
+            return (GraphicsContext.CurrentContext as IGraphicsContextInternal).GetAddress(funcname);
+        }
+    }
+}

Source/OpenTK/Graphics/ES10/Helper.cs

@@ -7,7 +7,7 @@ namespace OpenTK.Graphics.ES10
     /// <summary>
     /// Provides access to OpenGL ES 1.0 methods.
     /// </summary>
-    public sealed partial class GL : BindingsBase
+    public sealed partial class GL : GraphicsBindingsBase
     {
         const string Library = "libGLES.dll";
     }

Source/OpenTK/Graphics/ES11/Helper.cs

@@ -9,7 +9,7 @@ namespace OpenTK.Graphics.ES11
     /// <summary>
     /// Provides access to OpenGL ES 1.1 methods.
     /// </summary>
-    public sealed partial class GL : BindingsBase
+    public sealed partial class GL : GraphicsBindingsBase
     {
         const string Library = "libGLES.dll";
     }

Source/OpenTK/Graphics/ES20/Helper.cs

@@ -7,7 +7,7 @@ namespace OpenTK.Graphics.ES20
     /// <summary>
     /// Provides access to OpenGL ES 2.0 methods.
     /// </summary>
-    public sealed partial class GL : BindingsBase
+    public sealed partial class GL : GraphicsBindingsBase
     {
         const string Library = "libGLESv2.dll";
     }

Source/OpenTK/Graphics/OpenGL/GLHelper.cs

@@ -46,7 +46,7 @@ namespace OpenTK.Graphics.OpenGL
     /// </para>
     /// </remarks>
     /// <see href="http://opengl.org/registry/"/>
-    public sealed partial class GL : BindingsBase
+    public sealed partial class GL : GraphicsBindingsBase
     {
         #region --- Fields ---
 

Source/OpenTK/Platform/X11/GlxHelper.cs

@@ -15,13 +15,19 @@ using OpenTK.Graphics;
 
 namespace OpenTK.Platform.X11
 {
-    static partial class Glx
+    partial class Glx : BindingsBase
     {
         const string Library = "libGL.so.1";
 
         // Disable BeforeFieldInit optimization.
         static Glx() { }
 
+        protected override IntPtr GetAddress (string funcname)
+        {
+            return Glx.GetProcAddress(funcname);
+        }
+
+#if false
         #region static Delegate LoadDelegate(string name, Type signature)
 
         /// <summary>
@@ -83,5 +89,6 @@ namespace OpenTK.Platform.X11
         }
 
         #endregion
+#endif
     }
 }

Source/OpenTK/Platform/X11/X11GLContext.cs

@@ -59,7 +59,7 @@ namespace OpenTK.Platform.X11
 
                 if (ctx != IntPtr.Zero)
                 {
-                    Glx.LoadAll();
+                    new Glx().LoadAll();
                     Glx.MakeCurrent(currentWindow.Display, IntPtr.Zero, IntPtr.Zero);
                     //Glx.DestroyContext(currentWindow.Display, ctx);
                     glx_loaded = true;
@@ -271,7 +271,7 @@ namespace OpenTK.Platform.X11
         public override void LoadAll()
         {
             new OpenTK.Graphics.OpenGL.GL().LoadAll();
-            Glx.LoadAll();
+            new Glx().LoadAll();
             vsync_supported = this.GetAddress("glXSwapIntervalSGI") != IntPtr.Zero;
             Debug.Print("Context supports vsync: {0}.", vsync_supported);
         }