FontRenderer: Basic Rich Text processing and lazy text building

GlitchyEditor/src/EditWindows/ComponentEditWindow.bf

@@ -477,6 +477,18 @@ namespace GlitchyEditor.EditWindows
 
 		private static void ShowTextRendererComponentEditor(Entity entity, TextRendererComponent* textRendererComponent)
 		{
+			StartNewProperty("Rich text");
+
+			ImGui.AttachTooltip("If checked, the text will be interpreted as rich text. This means, that you can use tags to change the style of the text.");
+
+			bool isRichText = textRendererComponent.IsRichText;
+
+			if (ImGui.Checkbox("##rich_text", &isRichText))
+			{
+				textRendererComponent.IsRichText = isRichText;
+				textRendererComponent.NeedsRebuild = true;
+			}
+
 			StartNewProperty("Text");
 
 			String text = textRendererComponent.[Friend]_text;
@@ -498,6 +510,8 @@ namespace GlitchyEditor.EditWindows
 				{
 					text.Length = length;
 				}
+				
+				textRendererComponent.NeedsRebuild = true;
 			}
 		}
 

GlitchyEngine/src/Renderer/Text/FontRenderer.bf

@@ -135,6 +135,49 @@ namespace GlitchyEngine.Renderer.Text
 			case InvertCase;
 		}
 
+		class StyleStack<T>
+		{
+			private append List<T> _stack = .();
+
+			public this(T bottomValue)
+			{
+				_stack.Add(bottomValue);
+			}
+
+			public void Push(T value)
+			{
+				_stack.Add(value);
+			}
+
+			public T CurrentValue()
+			{
+				return _stack.Back;
+			}
+
+			public T Pop()
+			{
+				if (_stack.Count == 1)
+					return _stack[0];
+
+				return _stack.PopBack();
+			}
+
+			/// If popValue is true, the given value will not be pushed and the current top of the stack will be poped.
+			/// If popValaue is false, the given value will be pushed and returned.
+			public T PushButPopIfTrue(T value, bool popValue)
+			{
+				if (popValue)
+				{
+					return Pop();
+				}
+				else
+				{
+					Push(value);
+					return value;
+				}	
+			}
+		}	
+
 		public static PreparedText PrepareText(Font font, StringView text, float fontSize, Color fontColor = .White, Color bitmapColor = .White, float lineSpaceScale = 1.0f, TextDirection direction = .LeftToRight)
 		{
 			Debug.Profiler.ProfileRendererFunction!();
@@ -158,11 +201,11 @@ namespace GlitchyEngine.Renderer.Text
 			hb_buffer_t* buf = hb_buffer_create();
 
 			// Stack to keep track of the text direction.
-			List<TextDirection> textDirectionStack = scope .();
-			textDirectionStack.Add(direction);
+			StyleStack<TextDirection> textDirectionStack = scope .(direction);
 
-			List<TextCase> textCaseStack = scope .();
-			textCaseStack.Add(.RetainCase);
+			StyleStack<TextCase> textCaseStack = scope .(.RetainCase);
+			
+			StyleStack<bool> richTextStack = scope .(true);
 
 			int movedLines = 0;
 
@@ -185,7 +228,7 @@ namespace GlitchyEngine.Renderer.Text
 				// Set the script, language and direction of the buffer.
 				// TODO: change direction, script, etc.
 
-				TextDirection direction = textDirectionStack.Back;
+				TextDirection direction = textDirectionStack.CurrentValue();
 
 				switch (direction)
 				{
@@ -237,7 +280,7 @@ namespace GlitchyEngine.Renderer.Text
 
 			bool escapeNextChar = false;
 
-			for (char32 char in text.DecodedChars)
+			mainEnumerator: for (char32 char in text.DecodedChars)
 			{
 				defer
 				{
@@ -271,14 +314,14 @@ namespace GlitchyEngine.Renderer.Text
 					// LEFT-TO-RIGHT ISOLATE
 					FlushShapeBuffer();
 
-					textDirectionStack.Add(.RightToLeft);
+					textDirectionStack.Push(.RightToLeft);
 
 					continue;
 				case '\u{2067}':
 					// RIGHT-TO-LEFT ISOLATE
 					FlushShapeBuffer();
 
-					textDirectionStack.Add(.RightToLeft);
+					textDirectionStack.Push(.RightToLeft);
 
 					continue;
 				// TODO: FIRST STRONG ISOLATE (U+2068)
@@ -286,8 +329,7 @@ namespace GlitchyEngine.Renderer.Text
 					// POP DIRECTIONAL ISOLATE
 					FlushShapeBuffer();
 
-					if (textDirectionStack.Count > 1)
-						textDirectionStack.PopBack();
+					textDirectionStack.Pop();
 
 					continue;
 				case '\\':
@@ -331,6 +373,30 @@ namespace GlitchyEngine.Renderer.Text
 					if (isEndTag)
 						tagText.Remove(0);
 
+					tagText.ToLower();
+
+					if (tagText == "rt" || tagText == "richtext")
+					{
+						richTextStack.PushButPopIfTrue(true, isEndTag);
+						
+						// Skip the tag in the main enumerator
+						@char.NextIndex = endIndex;
+						continue;
+					}
+
+					if (tagText == "pt" || tagText == "plaintext")
+					{
+						richTextStack.PushButPopIfTrue(false, isEndTag);
+						
+						// Skip the tag in the main enumerator
+						@char.NextIndex = endIndex;
+						continue;
+					}
+
+					// Only process the other tags if we currently use rich text processing
+					if (!richTextStack.CurrentValue())
+						break;
+
 					switch(tagText)
 					{
 					case "b", "bold":
@@ -348,37 +414,24 @@ namespace GlitchyEngine.Renderer.Text
 
 						// Text case control
 					case "lc", "lowercase":
-						if (isEndTag && textCaseStack.Count > 0)
-							textCaseStack.PopBack();
-						else
-							textCaseStack.Add(.LowerCase);
+						textCaseStack.PushButPopIfTrue(.LowerCase, isEndTag);
 					case "uc", "uppercase":
-						if (isEndTag && textCaseStack.Count > 0)
-							textCaseStack.PopBack();
-						else
-							textCaseStack.Add(.UpperCase);
+						if (isEndTag)
+						textCaseStack.PushButPopIfTrue(.UpperCase, isEndTag);
 					case "rc", "retaincase":
-						if (isEndTag && textCaseStack.Count > 0)
-							textCaseStack.PopBack();
-						else
-							textCaseStack.Add(.RetainCase);
+						textCaseStack.PushButPopIfTrue(.RetainCase, isEndTag);
 					case "ic", "invertcase":
-						if (isEndTag && textCaseStack.Count > 0)
-							textCaseStack.PopBack();
-						else
-							textCaseStack.Add(.InvertCase);
-
+						textCaseStack.PushButPopIfTrue(.InvertCase, isEndTag);
 					}
 
 					// Skip the tag in the main enumerator
 					@char.NextIndex = endIndex;
-
 					continue;
 				}
 
 				escapeNextChar = false;
 
-				switch (textCaseStack.Back)
+				switch (textCaseStack.CurrentValue())
 				{
 				case .RetainCase:
 					// Nothing to do

GlitchyEngine/src/World/Components/TextRendererComponent.bf

@@ -1,11 +1,20 @@
 using System;
+using static GlitchyEngine.Renderer.Text.FontRenderer;
 namespace GlitchyEngine.World.Components;
 
+enum TextRendererFlags
+{
+	IsRichText = 1,
+	NeedsRebuild = 2
+}
+
 struct TextRendererComponent : IDisposableComponent
 {
 	private String _text;
 	
-	private bool _isRichText;
+	private PreparedText _preparedText;
+
+	private TextRendererFlags _flags;
 
 	public StringView Text
 	{
@@ -19,14 +28,27 @@ struct TextRendererComponent : IDisposableComponent
 		}
 	}
 
+	public PreparedText PreparedText
+	{
+		get => _preparedText;
+		set mut => SetReference!(_preparedText, value);
+	}
+
 	public bool IsRichText
 	{
-		get => _isRichText;
-		set mut => _isRichText = value;
+		get => _flags.HasFlag(.IsRichText);
+		set mut => Enum.SetFlagConditionally(ref _flags, .IsRichText, value);
+	}
+
+	public bool NeedsRebuild
+	{
+		get => _flags.HasFlag(.NeedsRebuild);
+		set mut => Enum.SetFlagConditionally(ref _flags, .NeedsRebuild, value);
 	}
 
 	public void Dispose()
 	{
 		delete _text;
+		_preparedText?.ReleaseRef();
 	}
 }

GlitchyEngine/src/World/Scene.bf

@@ -10,6 +10,8 @@ using GlitchyEngine.Math;
 using GlitchyEngine.Scripting.Classes;
 using GlitchyEngine.Serialization;
 using GlitchyEngine.World.Components;
+using GlitchyEngine.Renderer.Text;
+using static GlitchyEngine.Renderer.Text.FontRenderer;
 
 namespace GlitchyEngine.World
 {
@@ -56,6 +58,8 @@ namespace GlitchyEngine.World
 			cameraEntity
 		};
 		
+		Font _font ~ _.ReleaseRef();
+
 		/// Gets or sets the name of the scene.
 		public StringView Name
 		{
@@ -117,6 +121,8 @@ namespace GlitchyEngine.World
 					scene.InitPolygonCollider2D(e, collider);
 				}
 			});
+
+			_font = new Font(@"C:\Windows\Fonts\arial.ttf", 24);
 		}
 
 		public ~this()
@@ -768,6 +774,22 @@ namespace GlitchyEngine.World
 			}
 		}
 
+		private void BuildTexts()
+		{
+			for (let (entity, textRenderer) in _ecsWorld.Enumerate<TextRendererComponent>())
+			{
+				if (textRenderer.NeedsRebuild || textRenderer.PreparedText == null)
+				{
+					using (PreparedText preparedText = FontRenderer.PrepareText(_font, textRenderer.Text, 24, .Black))
+					{
+						textRenderer.PreparedText = preparedText;
+					}
+
+					textRenderer.NeedsRebuild = false;
+				}
+			}
+		}
+
 		public void Update(GameTime gameTime, UpdateMode mode)
 		{
 			Debug.Profiler.ProfileRendererFunction!();
@@ -807,6 +829,8 @@ namespace GlitchyEngine.World
 
 				_destroyQueue.Clear();
 			}
+
+			BuildTexts();
 		}
 
 		/// Creates a new Entity with the given name.

GlitchyEngine/src/World/SceneRenderer.bf

@@ -25,10 +25,6 @@ class SceneRenderer
 
 	public RenderTargetGroup CompositeTarget => _compositeTarget;
 
-	Font _font ~ _.ReleaseRef();
-
-	FontRenderer.PreparedText _smallLinesInfo;
-
 	public this()
 	{
 		RenderTargetGroupDescription desc = .(100, 100,
@@ -52,8 +48,6 @@ class SceneRenderer
 		_cameraTarget.[Friend]Identifier = "Camera Target";
 
 		_gammaCorrectEffect = Content.LoadAsset("Resources/Shaders/GammaCorrect.hlsl");
-
-		_font = new Font(@"C:\Windows\Fonts\arial.ttf", 24);
 	}
 
 	/// Sets the size of the viewport into which the scene will be rendered.
@@ -214,14 +208,10 @@ class SceneRenderer
 		
 		for (var (entity, transform, text, editorFlags) in Scene._ecsWorld.Enumerate<TransformComponent, TextRendererComponent, EditorFlagsComponent>())
 		{
-			if (editorFlags.Flags.HasFlag(.HideInScene))
+			if (editorFlags.Flags.HasFlag(.HideInScene) || text.PreparedText == null)
 				continue;
 			
-			_smallLinesInfo = FontRenderer.PrepareText(_font, text.Text, 24, .Black);
-
-			FontRenderer.DrawText(_smallLinesInfo, transform.WorldTransform * Matrix.Scaling(1.0f / 24.0f));
-
-			_smallLinesInfo.ReleaseRef();
+			FontRenderer.DrawText(text.PreparedText, transform.WorldTransform * Matrix.Scaling(1.0f / 24.0f));
 		}
 		
 		//FontRenderer.DrawText(_smallLinesInfo, 0, 0);