Merge pull request #106 from softwareantics/feature/public-glwpf-sett…

…ings

Added support to modify the GLWpfControlSettings within XAML front-end.

src/Example/MainWindow.xaml

@@ -12,7 +12,14 @@
     <Grid>
         <glWpfControl:GLWpfControl
             x:Name="OpenTkControl"
-            Render="OpenTkControl_OnRender" />
+            Render="OpenTkControl_OnRender">
+
+            <glWpfControl:GLWpfControl.Settings>
+                <glWpfControl:GLWpfControlSettings MajorVersion="2"
+                                                   MinorVersion="1"/>
+            </glWpfControl:GLWpfControl.Settings>
+
+        </glWpfControl:GLWpfControl>
         <Border
             HorizontalAlignment="Right"
             VerticalAlignment="Top"
@@ -32,7 +39,7 @@
             Height="128"
             HorizontalAlignment="Left"
             VerticalAlignment="Bottom"
-            Margin="10,0,0,60" />
+            Margin="10,0,0,60"/>
         <Button
             Content="Redraw Inset Control"
             HorizontalAlignment="Left"

src/Example/MainWindow.xaml.cs

@@ -9,10 +9,17 @@ namespace Example {
     public sealed partial class MainWindow {
         public MainWindow() {
             InitializeComponent();
-            var mainSettings = new GLWpfControlSettings {MajorVersion = 2, MinorVersion = 1};
-            OpenTkControl.Start(mainSettings);
-            var insetSettings = new GLWpfControlSettings {MajorVersion = 2, MinorVersion = 1, RenderContinuously = false};
-            InsetControl.Start(insetSettings);
+
+            // You can start and rely on the Settings property that may be set in XAML or elsewhere in the codebase.
+            OpenTkControl.Start();
+
+            // Or, you can suppy a settings object directly.
+            InsetControl.Start(new GLWpfControlSettings()
+            {
+                MajorVersion = 2,
+                MinorVersion = 1,
+                RenderContinuously = false,
+            });
         }
 
         private void OpenTkControl_OnRender(TimeSpan delta) {

src/GLWpfControl/DXGLContext.cs

@@ -87,9 +87,9 @@ internal sealed class DxGlContext : IDisposable {
             if (_sharedContext != null) {
                 var isSameContext = GLWpfControlSettings.WouldResultInSameContext(settings, _sharedContextSettings);
                 if (!isSameContext) {
-                    throw new ArgumentException($"The provided {nameof(GLWpfControlSettings)} would result" +
-                                                $"in a different context creation to one previously created. To fix this," +
-                                                $" either ensure all of your context settings are identical, or provide an " +
+                    throw new ArgumentException($"The provided {nameof(GLWpfControlSettings)} would result " +
+                                                $"in a different context creation to one previously created. To fix this, " +
+                                                $"either ensure all of your context settings are identical, or provide an " +
                                                 $"external context via the '{nameof(GLWpfControlSettings.ContextToUse)}' field.");
                 }
             } 

src/GLWpfControl/GLWpfControl.cs

@@ -41,25 +41,46 @@ public class GLWpfControl : FrameworkElement
         // -----------------------------------
         // Fields
         // -----------------------------------
-
-        [CanBeNull] private GLWpfControlSettings _settings;
+
+        /// <summary>
+        /// Represents the dependency property for <see cref="Settings"/>.
+        /// </summary>
+        public static readonly DependencyProperty SettingsProperty = DependencyProperty.Register(
+            "Settings", typeof(GLWpfControlSettings), typeof(GLWpfControl));
+
         [CanBeNull] private GLWpfControlRenderer _renderer;
 
+        /// <summary>
+        /// Indicates whether the <see cref="Start"/> function has been invoked.
+        /// </summary>
+        private bool _isStarted;
+
         // -----------------------------------
         // Properties
         // -----------------------------------
 
+        /// <summary>
+        /// Gets or sets the settings used when initializing the control.
+        /// </summary>
+        /// <value>
+        /// The settings used when initializing the control.
+        /// </value>
+        public GLWpfControlSettings Settings
+        {
+            get { return (GLWpfControlSettings)GetValue(SettingsProperty); }
+            set { SetValue(SettingsProperty, value); }
+        }
+
         /// The OpenGL Framebuffer Object used internally by this component.
         /// Bind to this instead of the default framebuffer when using this component along with other FrameBuffers for the final pass.
         /// If no framebuffer is available (because this control is not visible, etc etc, then it should be 0).
         public int Framebuffer => _renderer?.FrameBufferHandle ?? 0;
 
-
         /// If this control is rendering continuously.
         /// If this is false, then redrawing will only occur when <see cref="UIElement.InvalidateVisual"/> is called.
         public bool RenderContinuously {
-            get => _settings.RenderContinuously;
-            set => _settings.RenderContinuously = value;
+            get => Settings.RenderContinuously;
+            set => Settings.RenderContinuously = value;
         }
 
         /// Pixel width of the underlying OpenGL framebuffer.
@@ -85,14 +106,36 @@ public GLWpfControl() : base()
         {
         }
 
+        /// <summary>
+        /// Starts the control and rendering, using the settings provided via the <see cref="Settings"/> property.
+        /// </summary>
+        public void Start()
+        {
+            // Start with default settings if none were provided.
+            Settings ??= new GLWpfControlSettings();
+
+            Start(Settings);
+        }
+
+        /// <summary>
         /// Starts the control and rendering, using the settings provided.
+        /// </summary>
+        /// <param name="settings">
+        /// The settings used to construct the underlying graphics context.
+        /// </param>
+        /// <exception cref="InvalidOperationException">
+        /// The <see cref="Start"/> function must only be called once for a given <see cref="GLWpfControl"/>.
+        /// </exception>
         public void Start(GLWpfControlSettings settings)
         {
-            if (_settings != null) {
+            if (_isStarted) {
                 throw new InvalidOperationException($"{nameof(Start)} must only be called once for a given {nameof(GLWpfControl)}");
             }
-            _settings = settings.Copy();
-            _renderer = new GLWpfControlRenderer(_settings);
+
+            _isStarted = true;
+
+            Settings = settings.Copy();
+            _renderer = new GLWpfControlRenderer(Settings);
             _renderer.GLRender += timeDelta => Render?.Invoke(timeDelta);
             _renderer.GLAsyncRender += () => AsyncRender?.Invoke();
             IsVisibleChanged += (_, args) => {
@@ -106,10 +149,10 @@ public void Start(GLWpfControlSettings settings)
 
             // Inheriting directly from a FrameworkElement has issues with receiving certain events -- register for these events directly
             if (RegisterToEventsDirectly)
-	    {
-	        EventManager.RegisterClassHandler(typeof(Control), Keyboard.KeyDownEvent, new KeyEventHandler(OnKeyDown), CanInvokeOnHandledEvents);
-		EventManager.RegisterClassHandler(typeof(Control), Keyboard.KeyUpEvent, new KeyEventHandler(OnKeyUp), CanInvokeOnHandledEvents);
-	    }
+	        {
+	            EventManager.RegisterClassHandler(typeof(Control), Keyboard.KeyDownEvent, new KeyEventHandler(OnKeyDown), CanInvokeOnHandledEvents);
+		        EventManager.RegisterClassHandler(typeof(Control), Keyboard.KeyUpEvent, new KeyEventHandler(OnKeyUp), CanInvokeOnHandledEvents);
+	        }
 
             Loaded += (a, b) => {
                 InvalidateVisual();
@@ -119,14 +162,14 @@ public void Start(GLWpfControlSettings settings)
         }
 
         private void SetupRenderSize() {
-            if (_renderer == null || _settings == null) {
+            if (_renderer == null || Settings == null) {
                 return;
             }
 
             var dpiScaleX = 1.0;
             var dpiScaleY = 1.0;
 
-            if (_settings.UseDeviceDpi) {
+            if (Settings.UseDeviceDpi) {
                 var presentationSource = PresentationSource.FromVisual(this);
                 // this can be null in the case of not having any visual on screen, such as a tabbed view.
                 if (presentationSource != null) {
@@ -137,7 +180,8 @@ public void Start(GLWpfControlSettings settings)
                     dpiScaleY = transformToDevice.M22;
                 }
             }
-            var format = _settings.TransparentBackground ? Format.A8R8G8B8 : Format.X8R8G8B8;
+
+            var format = Settings.TransparentBackground ? Format.A8R8G8B8 : Format.X8R8G8B8;
             _renderer?.SetSize((int) RenderSize.Width, (int) RenderSize.Height, dpiScaleX, dpiScaleY, format);
         }
 
@@ -167,7 +211,6 @@ internal void OnKeyUp(object sender, KeyEventArgs e)
             }
         }
 
-
         private void OnCompTargetRender(object sender, EventArgs e)
         {
             var currentRenderTime = (e as RenderingEventArgs)?.RenderingTime;
@@ -211,6 +254,7 @@ protected override void OnRenderSizeChanged(SizeChangedInfo info)
             {
                 InvalidateVisual();
             }
+
             base.OnRenderSizeChanged(info);
         }
     }