1 files changed, 86 insertions, 0 deletions
diff --git a/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Editing/CaretLayer.cs b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Editing/CaretLayer.cs
new file mode 100644
index 000000000..105f38d16
--- /dev/null
+++ b/Software/Visual_Studio/Scripting/Tango.Scripting.Editors/Editing/CaretLayer.cs
@@ -0,0 +1,86 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
+
+using System;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Media;
+using System.Windows.Media.Animation;
+using System.Windows.Threading;
+
+using Tango.Scripting.Editors.Rendering;
+using Tango.Scripting.Editors.Utils;
+
+namespace Tango.Scripting.Editors.Editing
+{
+	sealed class CaretLayer : Layer
+	{
+		bool isVisible;
+		Rect caretRectangle;
+		
+		DispatcherTimer caretBlinkTimer = new DispatcherTimer();
+		bool blink;
+		
+		public CaretLayer(TextView textView) : base(textView, KnownLayer.Caret)
+		{
+			this.IsHitTestVisible = false;
+			caretBlinkTimer.Tick += new EventHandler(caretBlinkTimer_Tick);
+		}
+
+		void caretBlinkTimer_Tick(object sender, EventArgs e)
+		{
+			blink = !blink;
+			InvalidateVisual();
+		}
+		
+		public void Show(Rect caretRectangle)
+		{
+			this.caretRectangle = caretRectangle;
+			this.isVisible = true;
+			StartBlinkAnimation();
+			InvalidateVisual();
+		}
+		
+		public void Hide()
+		{
+			if (isVisible) {
+				isVisible = false;
+				StopBlinkAnimation();
+				InvalidateVisual();
+			}
+		}
+		
+		void StartBlinkAnimation()
+		{
+			TimeSpan blinkTime = Win32.CaretBlinkTime;
+			blink = true; // the caret should visible initially
+			// This is important if blinking is disabled (system reports a negative blinkTime)
+			if (blinkTime.TotalMilliseconds > 0) {
+				caretBlinkTimer.Interval = blinkTime;
+				caretBlinkTimer.Start();
+			}
+		}
+		
+		void StopBlinkAnimation()
+		{
+			caretBlinkTimer.Stop();
+		}
+		
+		internal Brush CaretBrush;
+		
+		protected override void OnRender(DrawingContext drawingContext)
+		{
+			base.OnRender(drawingContext);
+			if (isVisible && blink) {
+				Brush caretBrush = this.CaretBrush;
+				if (caretBrush == null)
+					caretBrush = (Brush)textView.GetValue(TextBlock.ForegroundProperty);
+				Rect r = new Rect(caretRectangle.X - textView.HorizontalOffset,
+				                  caretRectangle.Y - textView.VerticalOffset,
+				                  caretRectangle.Width,
+				                  caretRectangle.Height);
+				drawingContext.DrawRectangle(caretBrush, null, PixelSnapHelpers.Round(r, PixelSnapHelpers.GetPixelSize(this)));
+			}
+		}
+	}
+}