From 4435d1a5da99dddeedfcf48a687e6d4ebee7227d Mon Sep 17 00:00:00 2001
From: Emmanuel <nhv3@localhost.localdomain>
Date: Tue, 8 Sep 2020 08:36:51 +0000
Subject: [PATCH] 1.0.3pre1

---
 GLWidget/GLWidget.cs         | 55 ++++++++++++++++++++++++++++--------
 GLWidget/GTKBindingHelper.cs | 18 +++++++++++-
 GLWidget/GraphicsContext.cs  | 44 +++++++++++++++++++++++++++++
 3 files changed, 104 insertions(+), 13 deletions(-)

diff --git a/GLWidget/GLWidget.cs b/GLWidget/GLWidget.cs
index af8e0e0..511c645 100644
--- a/GLWidget/GLWidget.cs
+++ b/GLWidget/GLWidget.cs
@@ -174,6 +174,7 @@ namespace OpenTK
         private int _error;
 
 		private IGraphicsContext _context;
+        private GLContext _gdkGlContext;
 
         public bool ForwardCompatible { get; }
         public DeviceContext DeviceContext { get => _deviceContext; set => _deviceContext = value; }
@@ -209,10 +210,12 @@ namespace OpenTK
 			{
 				OnShuttingDown();
 
-				DeviceContext.DeleteContext(_graphicsContext);
+				DeviceContext?.DeleteContext(_graphicsContext);
 
-				DeviceContext.Dispose();
-			}
+				DeviceContext?.Dispose();
+
+                _gdkGlContext?.Dispose();
+            }
 		}
 
 		#endregion
@@ -271,7 +274,7 @@ namespace OpenTK
 
         public void Swapbuffers()
         {
-           DeviceContext?.SwapBuffers();
+            _context?.SwapBuffers();
         }
 
 		public void MakeCurrent()
@@ -285,9 +288,15 @@ namespace OpenTK
 
         public void ClearCurrent()
 		{
-			//Gdk.GLContext.ClearCurrent();
-			DeviceContext?.MakeCurrent(IntPtr.Zero);
-		}
+            if (GTKBindingHelper.CurrentPlatform == OSPlatform.Windows)
+            {
+                DeviceContext?.MakeCurrent(IntPtr.Zero);
+            }
+            else
+            {
+            	Gdk.GLContext.ClearCurrent();
+            }
+        }
 
 		private void CreateContext()
 		{
@@ -404,20 +413,42 @@ namespace OpenTK
 			#endregion
 		}
 
-		private void Initialize()
+        private void CreateGdkGlContext()
+        {
+            _gdkGlContext = Window.CreateGlContext();
+
+            _gdkGlContext.SetRequiredVersion(GLVersionMajor, GLVersionMinor);
+
+            _gdkGlContext.ForwardCompatible = ForwardCompatible;
+
+            _gdkGlContext.SetUseEs(0);
+
+            _gdkGlContext.Realize();
+
+            _gdkGlContext.MakeCurrent();
+        }
+
+        private void Initialize()
 		{
 			ClearCurrent();
 
             Khronos.KhronosApi.LogEnabled = true;
-			Wgl.ErrorHandling = Wgl.ErrorHandlingMode.Normal;
 
 			Window.EnsureNative();
 
-			CreateDeviceContext(ControlPixelFormat);
+            if (GTKBindingHelper.CurrentPlatform == OSPlatform.Windows)
+            {
+                CreateDeviceContext(ControlPixelFormat);
 
-			CreateContext();
+                CreateContext();
 
-			DeviceContext.MakeCurrent(_graphicsContext);
+                DeviceContext.MakeCurrent(_graphicsContext);
+            }
+			else {
+                GraphicsContext.Display = Display.Handle;
+
+                CreateGdkGlContext();
+            }
 
 			_context = GraphicsContext.GetCurrentContext(Window.Handle);
 
diff --git a/GLWidget/GTKBindingHelper.cs b/GLWidget/GTKBindingHelper.cs
index 2451e3f..7e16306 100644
--- a/GLWidget/GTKBindingHelper.cs
+++ b/GLWidget/GTKBindingHelper.cs
@@ -67,7 +67,7 @@ namespace OpenTK
             }
             else if(CurrentPlatform == OSPlatform.OSX)
             {
-                var osxAddr = !IsGlxRequired ? GetProcAddressOSX(procName) : GetProcAddressGlx(procName);
+                var osxAddr = GetProcAddressOSX(procName);
                 if (osxAddr != IntPtr.Zero)
                 {
                     Loaded = true;
@@ -242,6 +242,22 @@ namespace OpenTK
             [DllImport(OSXLibrary, EntryPoint = "NSAddressOfSymbol")]
             public static extern IntPtr NSAddressOfSymbol(IntPtr symbol);
 
+            [DllImport(OSXLibrary)]
+            public extern static int CGLSetCurrentContext(IntPtr ctx);
+
+            [DllImport(OSXLibrary)]
+            public extern static IntPtr CGLGetCurrentContext();
+            [DllImport(OSXLibrary)]
+            public extern static void CGLReleaseContext(IntPtr ctx);
+            [DllImport(OSXLibrary)]
+            public extern static int CGLFlushDrawable(IntPtr ctx);
+
+            [DllImport(OSXLibrary)]
+            internal static extern int CGLDestroyContext(IntPtr ctx);
+
+            [DllImport(OSXLibrary)]
+            internal static extern int CGLSetParameter(IntPtr ctx, int parameter, ref int value);
+
             [DllImport(GlxLibrary, EntryPoint = "glXGetCurrentContext")]
             public static extern IntPtr glXGetCurrentContext();
 
diff --git a/GLWidget/GraphicsContext.cs b/GLWidget/GraphicsContext.cs
index 191bb80..f9f9961 100644
--- a/GLWidget/GraphicsContext.cs
+++ b/GLWidget/GraphicsContext.cs
@@ -54,6 +54,10 @@ namespace OpenTK
                 }
                 return GlxGraphicsContext.GetCurrent(handle, Display);
             }
+            else if (currentPlatform == OSPlatform.OSX)
+            {
+                return CglGraphicsContext.GetCurrent();
+            }
 
             return null;
         }
@@ -157,4 +161,44 @@ namespace OpenTK
             UnsafeNativeMethods.glXSwapIntervalEXT(interval);
         }
     }
+
+    public class CglGraphicsContext : GraphicsContext
+    {
+        private IntPtr _windowHandle;
+
+        public static CglGraphicsContext GetCurrent()
+        {
+            var gc = UnsafeNativeMethods.CGLGetCurrentContext();
+
+            return new CglGraphicsContext(gc);
+        }
+
+        public CglGraphicsContext(IntPtr graphicsContext)
+        {
+            _graphicsContext = graphicsContext;
+        }
+
+        private IntPtr _graphicsContext;
+        private IntPtr _display;
+
+        public override void MakeCurrent()
+        {
+            UnsafeNativeMethods.CGLSetCurrentContext(_graphicsContext);
+        }
+
+        public override void SwapBuffers()
+        {
+            UnsafeNativeMethods.CGLFlushDrawable(_graphicsContext);
+        }
+
+        public override void ClearCurrent()
+        {
+            UnsafeNativeMethods.CGLSetCurrentContext(IntPtr.Zero);
+        }
+
+        public override void SwapInterval(int interval)
+        {
+            UnsafeNativeMethods.CGLSetParameter(_graphicsContext, 222 , ref interval);
+        }
+    }
 }
\ No newline at end of file