IDisplayView, render statistics

src/Library/TerminalUI/Controls/Border.cs

@@ -1,9 +1,10 @@
-using PropertyChanged.SourceGenerator;
+using PropertyChanged.SourceGenerator;
 using TerminalUI.Models;
+using TerminalUI.Traits;
 
 namespace TerminalUI.Controls;
 
-public partial class Border<T> : ContentView<T>
+public partial class Border<T> : ContentView<T>, IDisplayView
 {
     [Notify] private Thickness _borderThickness = 1;
     [Notify] private Thickness _padding = 0;

src/Library/TerminalUI/Controls/Rectangle.cs

@@ -1,10 +1,11 @@
 using PropertyChanged.SourceGenerator;
 using TerminalUI.Color;
 using TerminalUI.Models;
+using TerminalUI.Traits;
 
 namespace TerminalUI.Controls;
 
-public partial class Rectangle<T> : View<T>
+public partial class Rectangle<T> : View<T>, IDisplayView
 {
     private record RenderState(
         Position Position,

src/Library/TerminalUI/Controls/TextBlock.cs

@@ -1,14 +1,15 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using System.Diagnostics;
 using PropertyChanged.SourceGenerator;
 using TerminalUI.Color;
 using TerminalUI.Extensions;
 using TerminalUI.Models;
+using TerminalUI.Traits;
 
 namespace TerminalUI.Controls;
 
 [DebuggerDisplay("Text = {Text}")]
-public partial class TextBlock<T> : View<T>
+public partial class TextBlock<T> : View<T>, IDisplayView
 {
     private record RenderState(
         Position Position,

src/Library/TerminalUI/Controls/TextBox.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics;
 using GeneralInputKey;
 using PropertyChanged.SourceGenerator;
 using TerminalUI.Color;
@@ -7,7 +8,8 @@ using TerminalUI.Traits;
 
 namespace TerminalUI.Controls;
 
-public partial class TextBox<T> : View<T>, IFocusable
+[DebuggerDisplay("Text = {Text}")]
+public partial class TextBox<T> : View<T>, IFocusable, IDisplayView
 {
     private record RenderState(
         string? Text,

src/Library/TerminalUI/Controls/View.cs

@@ -1,4 +1,4 @@
-using System.Buffers;
+using System.Buffers;
 using System.Collections.ObjectModel;
 using System.ComponentModel;
 using System.Runtime.CompilerServices;
@@ -6,6 +6,7 @@ using PropertyChanged.SourceGenerator;
 using TerminalUI.Color;
 using TerminalUI.ConsoleDrivers;
 using TerminalUI.Models;
+using TerminalUI.Traits;
 
 namespace TerminalUI.Controls;
 
@@ -118,6 +119,7 @@ public abstract partial class View<T> : IView<T>
 
     public bool Render(in RenderContext renderContext, Position position, Size size)
     {
+        renderContext.Statistics.ProcessedViews++;
         if (!Attached)
             throw new InvalidOperationException("Cannot render unattached view");
 
@@ -149,7 +151,16 @@ public abstract partial class View<T> : IView<T>
             );
         }
 
-        return RenderMethod(renderContext, position, size);
+        var renderResult = RenderMethod(renderContext, position, size);
+        if (renderResult)
+        {
+            renderContext.Statistics.RenderedViews++;
+
+            if (this is IDisplayView)
+                renderContext.Statistics.RenderedDisplayViews++;
+        }
+
+        return renderResult;
     }
 
     protected void RenderEmpty(in RenderContext renderContext, Position position, Size size)

src/Library/TerminalUI/Models/RenderContext.cs

@@ -13,20 +13,30 @@ public readonly ref struct RenderContext
     public readonly bool ForceRerender;
     public readonly IColor? Foreground;
     public readonly IColor? Background;
+    public readonly RenderStatistics Statistics;
 
     public RenderContext(
-        IConsoleDriver consoleDriver, 
-        bool forceRerender, 
-        IColor? foreground, 
-        IColor? background)
+        IConsoleDriver consoleDriver,
+        bool forceRerender,
+        IColor? foreground,
+        IColor? background,
+        RenderStatistics statistics)
     {
         RenderId = _renderId++;
-        
+
         ConsoleDriver = consoleDriver;
         ForceRerender = forceRerender;
         Foreground = foreground;
         Background = background;
+        Statistics = statistics;
     }
-    
-    public static RenderContext Empty => new(null!, false, null, null);
+
+    public static RenderContext Empty =>
+        new(
+            null!,
+            false,
+            null,
+            null,
+            new RenderStatistics()
+        );
 }

src/Library/TerminalUI/Models/RenderStatistics.cs

@@ -0,0 +1,11 @@
+using System.Diagnostics;
+
+namespace TerminalUI.Models;
+
+[DebuggerDisplay("RenderedViews = {RenderedViews}, RenderedDisplayViews = {RenderedDisplayViews}, ProcessedViews = {ProcessedViews}")]
+public class RenderStatistics
+{
+    public ulong RenderedViews { get; set; }
+    public ulong RenderedDisplayViews { get; set; }
+    public ulong ProcessedViews { get; set; }
+}

src/Library/TerminalUI/RenderEngine.cs

@@ -1,4 +1,4 @@
-using TerminalUI.Controls;
+using TerminalUI.Controls;
 using TerminalUI.Models;
 using TerminalUI.Traits;
 
@@ -82,7 +82,8 @@ public class RenderEngine : IRenderEngine
                 driver,
                 true,
                 null,
-                null
+                null,
+                new RenderStatistics()
             ),
             initialPosition,
             size);
@@ -93,7 +94,8 @@ public class RenderEngine : IRenderEngine
                 driver,
                 false,
                 null,
-                null
+                null,
+                new RenderStatistics()
             ),
             initialPosition,
             size);

src/Library/TerminalUI/Traits/IDisplayView.cs

@@ -0,0 +1,6 @@
+namespace TerminalUI.Traits;
+
+public interface IDisplayView
+{
+    
+}