Merge pull request #8998 from Gillibald/fixes/bidiMirrors

Fix bidi mirror handling

src/Avalonia.Base/Media/GlyphRun.cs

@@ -361,7 +361,9 @@ namespace Avalonia.Media
 
                     characterIndex = cluster;
 
-                    if (currentX - advance < distance)
+                    var offsetX = currentX - advance;
+
+                    if (offsetX < distance)
                     {
                         break;
                     }
@@ -375,7 +377,8 @@ namespace Avalonia.Media
             var characterHit = FindNearestCharacterHit(characterIndex, out var width);
 
             var delta = width / 2;
-            var offset = IsLeftToRight ? distance - currentX : currentX - distance;
+            
+            var offset = IsLeftToRight ? Math.Round(distance - currentX, 3) : Math.Round(currentX - distance, 3);
 
             var isTrailing = offset > delta;
 

src/Avalonia.Base/Media/TextFormatting/TextCharacters.cs

@@ -76,7 +76,7 @@ namespace Avalonia.Media.TextFormatting
             {
                 if (script == Script.Common && previousTypeface is not null)
                 {
-                    if (TryGetShapeableLength(text, previousTypeface.Value, defaultTypeface, out var fallbackCount, out _))
+                    if (TryGetShapeableLength(text, previousTypeface.Value, null, out var fallbackCount, out _))
                     {
                         return new ShapeableTextCharacters(text.Take(fallbackCount),
                             defaultProperties.WithTypeface(previousTypeface.Value), biDiLevel);

src/Avalonia.Base/Media/TextFormatting/Unicode/BiDiData.cs

@@ -71,9 +71,6 @@ namespace Avalonia.Media.TextFormatting.Unicode
 
             // Resolve the BidiCharacterType, paired bracket type and paired
             // bracket values for all code points
-            HasBrackets = false;
-            HasEmbeddings = false;
-            HasIsolates = false;
 
             int i = Length;
              

src/Skia/Avalonia.Skia/TextShaperImpl.cs

@@ -27,7 +27,7 @@ namespace Avalonia.Skia
                 
                 buffer.GuessSegmentProperties();
 
-                buffer.Direction = Direction.LeftToRight; //Always shape LeftToRight
+                buffer.Direction = (bidiLevel & 1) == 0 ? Direction.LeftToRight : Direction.RightToLeft;
 
                 buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);              
 
@@ -35,6 +35,11 @@ namespace Avalonia.Skia
 
                 font.Shape(buffer);
 
+                if(buffer.Direction == Direction.RightToLeft)
+                {
+                    buffer.Reverse();
+                }
+
                 font.GetScale(out var scaleX, out _);
 
                 var textScale = fontRenderingEmSize / scaleX;

src/Windows/Avalonia.Direct2D1/Media/TextShaperImpl.cs

@@ -27,7 +27,7 @@ namespace Avalonia.Direct2D1.Media
 
                 buffer.GuessSegmentProperties();
 
-                buffer.Direction = Direction.LeftToRight; //Always shape LeftToRight
+                buffer.Direction = (bidiLevel & 1) == 0 ? Direction.LeftToRight : Direction.RightToLeft;
 
                 buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);
 
@@ -35,6 +35,11 @@ namespace Avalonia.Direct2D1.Media
 
                 font.Shape(buffer);
 
+                if(buffer.Direction == Direction.RightToLeft)
+                {
+                    buffer.Reverse();
+                }
+
                 font.GetScale(out var scaleX, out _);
 
                 var textScale = fontRenderingEmSize / scaleX;

tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextLayoutTests.cs

@@ -1009,7 +1009,10 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                         currentX += glyphAdvance;
 
-                        cluster = clusters[j];
+                        if(glyphAdvance > 0)
+                        {
+                            cluster = clusters[j];
+                        }
                     }
                 }
             }