Bubble some OpenGL elements up to the DC impl.

Dashboard.Common/Pal/DeviceContext.cs

@@ -1,10 +1,10 @@
+using System.Numerics;
 using Dashboard.Collections;
 using Dashboard.Windowing;
-using BindingFlags = System.Reflection.BindingFlags;
 
 namespace Dashboard.Pal
 {
-    public abstract class DeviceContext : IContextBase<DeviceContext, IDeviceContextExtension>
+    public abstract class DeviceContext : IContextBase<DeviceContext, IDeviceContextExtension>, IDeviceContext
     {
         private readonly TypeDictionary<IDeviceContextExtension> _extensions =
             new TypeDictionary<IDeviceContextExtension>(true);
@@ -19,6 +19,9 @@ namespace Dashboard.Pal
         public abstract string DriverName { get; }
         public abstract string DriverVendor { get; }
         public abstract Version DriverVersion { get; }
+        public abstract ISwapGroup SwapGroup { get; }
+        public abstract Vector2 FramebufferSize { get; }
+        public virtual bool DoubleBuffered { get; } = false;
 
         public bool IsDisposed { get; private set; }
 

Dashboard.OpenGL/GLDeviceContext.cs

@@ -1,5 +1,6 @@
 using System.Collections.Concurrent;
 using System.Collections.Immutable;
+using System.Numerics;
 using Dashboard.Drawing;
 using Dashboard.OpenGL.Drawing;
 using Dashboard.Pal;
@@ -27,6 +28,9 @@ namespace Dashboard.OpenGL
         public override string DriverName     => "Dashboard OpenGL Device Context";
         public override string DriverVendor   => "Dashboard";
         public override Version DriverVersion => new Version(0, 1, 0);
+        public override ISwapGroup SwapGroup { get; }
+        public override Vector2 FramebufferSize => GLContext.FramebufferSize;
+        public override bool DoubleBuffered { get; } = true;
 
         public Version GLVersion { get; }
         public string GLRenderer { get; }
@@ -39,9 +43,11 @@ namespace Dashboard.OpenGL
         private readonly ConcurrentQueue<Task> _beforeDrawActions = new ConcurrentQueue<Task>();
         private readonly ConcurrentQueue<Task> _afterDrawActions = new ConcurrentQueue<Task>();
 
-        public GLDeviceContext(Application app, IWindow? window, IGLContext context) : base(app, window)
+        public GLDeviceContext(Application app, IWindow? window, IGLContext context, ISwapGroup swap) : base(app, window)
         {
             GLContext = context;
+            SwapGroup = swap;
+
             context.MakeCurrent();
             GLLoader.LoadBindings(new GLContextBindingsContext(context));
 

Dashboard.OpenGL/IGLContext.cs

@@ -14,11 +14,6 @@ namespace Dashboard.OpenGL
         /// <remarks>-1 assigns no group.</remarks>
         public int ContextGroup { get; }
 
-        /// <summary>
-        /// The size of the framebuffer in pixels.
-        /// </summary>
-        public Vector2 FramebufferSize { get; }
-
         /// <summary>
         /// Called when the context is disposed.
         /// </summary>

Dashboard.OpenTK/PAL2/PhysicalWindow.cs

@@ -64,7 +64,7 @@ namespace Dashboard.OpenTK.PAL2
         {
             Application = app;
             WindowHandle = window;
-            DeviceContext = new GLDeviceContext(app, this, new Pal2GLContext(window, context));
+            DeviceContext = new GLDeviceContext(app, this, new Pal2GLContext(window, context), new DummySwapGroup(context));
         }
 
         public PhysicalWindow(Application app, GraphicsApiHints hints)
@@ -81,7 +81,8 @@ namespace Dashboard.OpenTK.PAL2
             {
             case GraphicsApi.OpenGL:
             case GraphicsApi.OpenGLES:
-                return new GLDeviceContext(app, window, new Pal2GLContext(handle, TK.OpenGL.CreateFromWindow(handle)));
+                OpenGLContextHandle context = TK.OpenGL.CreateFromWindow(handle);
+                return new GLDeviceContext(app, window, new Pal2GLContext(handle, context), new DummySwapGroup(context));
             default:
                 throw new Exception($"Unknown graphics API {hints.Api}.");
             }
@@ -146,5 +147,28 @@ namespace Dashboard.OpenTK.PAL2
                 return Math.Max(x, y);
             }
         }
+
+        private class DummySwapGroup(OpenGLContextHandle context) : ISwapGroup
+        {
+            public int SwapInterval
+            {
+                get
+                {
+                    TK.OpenGL.SetCurrentContext(context);
+                    return TK.OpenGL.GetSwapInterval();
+                }
+
+                set
+                {
+                    TK.OpenGL.SetCurrentContext(context);
+                    TK.OpenGL.SetSwapInterval(value);
+                }
+            }
+
+            public void Swap()
+            {
+                TK.OpenGL.SwapBuffers(context);
+            }
+        }
     }
 }