feat: implement MSDF text rendering components and tests

lib/Graphics/Containers/IMsdfTextPart.cs

@@ -0,0 +1,12 @@
+using osu.Framework.Graphics;
+
+namespace kajarlabs.osu.Framework.MsdfTextRendering.Graphics.Containers;
+
+public interface IMsdfTextPart
+{
+    IEnumerable<Drawable> Drawables { get; }
+
+    event Action<IEnumerable<Drawable>>? DrawablePartsRecreated;
+
+    void RecreateDrawablesFor(MsdfTextFlowContainer textFlowContainer);
+}

lib/Graphics/Containers/MsdfTextChunk.cs

@@ -0,0 +1,115 @@
+using System.Globalization;
+using System.Text;
+using kajarlabs.osu.Framework.MsdfTextRendering.Graphics.Sprites;
+using osu.Framework.Graphics;
+using osu.Framework.Localisation;
+
+namespace kajarlabs.osu.Framework.MsdfTextRendering.Graphics.Containers;
+
+public class MsdfTextChunk<TMsdfSpriteText> : MsdfTextPart
+    where TMsdfSpriteText : MsdfSpriteText, new()
+{
+    private readonly LocalisableString text;
+    private readonly bool newLineIsParagraph;
+    private readonly Func<TMsdfSpriteText> creationFunc;
+    private readonly Action<TMsdfSpriteText>? creationParameters;
+
+    public MsdfTextChunk(LocalisableString text, bool newLineIsParagraph, Func<TMsdfSpriteText> creationFunc, Action<TMsdfSpriteText>? creationParameters = null)
+    {
+        this.text = text;
+        this.newLineIsParagraph = newLineIsParagraph;
+        this.creationFunc = creationFunc;
+        this.creationParameters = creationParameters;
+    }
+
+    protected override IEnumerable<Drawable> CreateDrawablesFor(MsdfTextFlowContainer textFlowContainer)
+    {
+        var currentContent = textFlowContainer.Localisation?.GetLocalisedString(text) ?? text.ToString();
+
+        var drawables = new List<Drawable>();
+
+        if (!newLineIsParagraph)
+        {
+            var newLine = new MsdfTextNewLine(true);
+
+            newLine.RecreateDrawablesFor(textFlowContainer);
+            drawables.AddRange(newLine.Drawables);
+        }
+
+        drawables.AddRange(CreateDrawablesFor(currentContent, textFlowContainer));
+        return drawables;
+    }
+
+    protected virtual IEnumerable<Drawable> CreateDrawablesFor(string text, MsdfTextFlowContainer textFlowContainer)
+    {
+        var first = true;
+        var sprites = new List<Drawable>();
+
+        foreach (var l in text.Split('\n'))
+        {
+            if (!first)
+            {
+                var lastChild = sprites.LastOrDefault() ?? textFlowContainer.Children.LastOrDefault();
+
+                if (lastChild != null)
+                {
+                    var newLine = new MsdfTextFlowContainer.NewLineContainer(newLineIsParagraph);
+
+                    sprites.Add(newLine);
+                }
+            }
+
+            foreach (var word in SplitWords(l))
+            {
+                if (string.IsNullOrEmpty(word)) continue;
+
+                var textSprite = CreateSpriteText(textFlowContainer);
+
+                textSprite.Text = word;
+                sprites.Add(textSprite);
+            }
+
+            first = false;
+        }
+
+        return sprites;
+    }
+
+    protected string[] SplitWords(string text)
+    {
+        var words = new List<string>();
+        var builder = new StringBuilder();
+
+        for (var i = 0; i < text.Length; i++)
+        {
+            if (i == 0
+                || char.IsSeparator(text[i - 1])
+                || char.IsControl(text[i - 1])
+                || char.GetUnicodeCategory(text[i - 1]) == UnicodeCategory.DashPunctuation
+                || text[i - 1] == '/'
+                || text[i - 1] == '\\'
+                || (isCjkCharacter(text[i - 1]) && !char.IsPunctuation(text[i])))
+            {
+                words.Add(builder.ToString());
+                builder.Clear();
+            }
+
+            builder.Append(text[i]);
+        }
+
+        if (builder.Length > 0)
+            words.Add(builder.ToString());
+
+        return words.ToArray();
+
+        static bool isCjkCharacter(char c) => c >= '\x2E80' && c <= '\x9FFF';
+    }
+
+    protected virtual TMsdfSpriteText CreateSpriteText(MsdfTextFlowContainer textFlowContainer)
+    {
+        var spriteText = creationFunc.Invoke();
+        textFlowContainer.ApplyDefaultCreationParameters(spriteText);
+        creationParameters?.Invoke(spriteText);
+        return spriteText;
+    }
+}