Merge pull request #8053 from Gillibald/fixes/textProcessingBugs

Fix text processing bugs

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

@@ -528,7 +528,7 @@ namespace Avalonia.Media.TextFormatting
         /// Creates an empty text line.
         /// </summary>
         /// <returns>The empty text line.</returns>
-        public static TextLineImpl CreateEmptyTextLine(int firstTextSourceIndex, TextParagraphProperties paragraphProperties)
+        public static TextLineImpl CreateEmptyTextLine(int firstTextSourceIndex, double paragraphWidth, TextParagraphProperties paragraphProperties)
         {
             var flowDirection = paragraphProperties.FlowDirection;
             var properties = paragraphProperties.DefaultTextRunProperties;
@@ -542,7 +542,7 @@ namespace Avalonia.Media.TextFormatting
 
             var textRuns = new List<DrawableTextRun> { new ShapedTextCharacters(shapedBuffer, properties) };
 
-            return new TextLineImpl(textRuns, firstTextSourceIndex, 0, double.PositiveInfinity, paragraphProperties, flowDirection).FinalizeLine();
+            return new TextLineImpl(textRuns, firstTextSourceIndex, 0, paragraphWidth, paragraphProperties, flowDirection).FinalizeLine();
         }
 
         /// <summary>
@@ -561,7 +561,7 @@ namespace Avalonia.Media.TextFormatting
         {
             if(textRuns.Count == 0)
             {
-                return CreateEmptyTextLine(firstTextSourceIndex, paragraphProperties);
+                return CreateEmptyTextLine(firstTextSourceIndex,paragraphWidth, paragraphProperties);
             }
 
             if (!TryMeasureLength(textRuns, paragraphWidth, out var measuredLength))

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

@@ -410,7 +410,7 @@ namespace Avalonia.Media.TextFormatting
         {
             if (MathUtilities.IsZero(MaxWidth) || MathUtilities.IsZero(MaxHeight))
             {
-                var textLine = TextFormatterImpl.CreateEmptyTextLine(0, _paragraphProperties);
+                var textLine = TextFormatterImpl.CreateEmptyTextLine(0, double.PositiveInfinity, _paragraphProperties);
 
                 Bounds = new Rect(0,0,0, textLine.Height);
 
@@ -434,7 +434,7 @@ namespace Avalonia.Media.TextFormatting
                 {
                     if(previousLine != null && previousLine.NewLineLength  > 0)
                     {
-                        var emptyTextLine = TextFormatterImpl.CreateEmptyTextLine(_textSourceLength, _paragraphProperties);
+                        var emptyTextLine = TextFormatterImpl.CreateEmptyTextLine(_textSourceLength, MaxWidth, _paragraphProperties);
 
                         textLines.Add(emptyTextLine);
 
@@ -483,7 +483,7 @@ namespace Avalonia.Media.TextFormatting
             //Make sure the TextLayout always contains at least on empty line
             if(textLines.Count == 0)
             {
-                var textLine = TextFormatterImpl.CreateEmptyTextLine(0, _paragraphProperties);
+                var textLine = TextFormatterImpl.CreateEmptyTextLine(0, MaxWidth, _paragraphProperties);
 
                 textLines.Add(textLine);
 

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

@@ -252,7 +252,7 @@ namespace Avalonia.Media.TextFormatting
                             //Look at the left and right edge of the current run
                             if (currentRun.IsLeftToRight)
                             {
-                                if (lastRun == null || lastRun.IsLeftToRight)
+                                if (_flowDirection == FlowDirection.LeftToRight && (lastRun == null || lastRun.IsLeftToRight))
                                 {
                                     if (characterIndex <= textRun.Text.Start)
                                     {
@@ -418,11 +418,6 @@ namespace Avalonia.Media.TextFormatting
                     continue;
                 }
 
-                if(currentPosition + currentRun.TextSourceLength <= firstTextSourceCharacterIndex)
-                {
-                    continue;
-                }
-
                 TextRun? nextRun = null;
 
                 if (index + 1 < TextRuns.Count)
@@ -460,7 +455,7 @@ namespace Avalonia.Media.TextFormatting
                             }
                         default:
                             {
-                               goto noop;
+                                goto noop;
                             }
                     }
 
@@ -541,6 +536,11 @@ namespace Avalonia.Media.TextFormatting
                                 endX += currentRun.Size.Width;
                             }
 
+                            if (currentPosition < firstTextSourceCharacterIndex)
+                            {
+                                startX += currentRun.Size.Width;
+                            }
+
                             currentPosition += currentRun.TextSourceLength;
 
                             break;
@@ -554,24 +554,29 @@ namespace Avalonia.Media.TextFormatting
 
                 var width = endX - startX;
 
-                if (lastDirection == currentDirection && result.Count > 0 && MathUtilities.AreClose(currentRect.Right, startX))
+                if (!MathUtilities.IsZero(width))
                 {
-                    currentRect = currentRect.WithWidth(currentRect.Width + width);
+                    if (lastDirection == currentDirection && result.Count > 0 && MathUtilities.AreClose(currentRect.Right, startX))
+                    {
+                        currentRect = currentRect.WithWidth(currentRect.Width + width);
 
-                    var textBounds = new TextBounds(currentRect, currentDirection);
+                        var textBounds = new TextBounds(currentRect, currentDirection);
 
-                    result[result.Count - 1] = textBounds;
-                }
-                else
-                {
-                    currentRect = new Rect(startX, 0, width, Height);
+                        result[result.Count - 1] = textBounds;
+                    }
+                    else
+                    {
 
-                    result.Add(new TextBounds(currentRect, currentDirection));
+                        currentRect = new Rect(startX, 0, width, Height);
+
+                        result.Add(new TextBounds(currentRect, currentDirection));
+
+                    }
                 }
 
                 if (currentDirection == FlowDirection.LeftToRight)
                 {
-                    if (currentPosition >= firstTextSourceCharacterIndex + textLength)
+                    if (currentPosition > firstTextSourceCharacterIndex + textLength)
                     {
                         break;
                     }
@@ -595,10 +600,10 @@ namespace Avalonia.Media.TextFormatting
 
         public TextLineImpl FinalizeLine()
         {
-            BidiReorder();
-
             _textLineMetrics = CreateLineMetrics();
 
+            BidiReorder();
+
             return this;
         }
 
@@ -1026,7 +1031,7 @@ namespace Avalonia.Media.TextFormatting
             var glyphTypeface = _paragraphProperties.DefaultTextRunProperties.Typeface.GlyphTypeface;
             var fontRenderingEmSize = _paragraphProperties.DefaultTextRunProperties.FontRenderingEmSize;
             var scale = fontRenderingEmSize / glyphTypeface.DesignEmHeight;
-          
+
             var width = 0d;
             var widthIncludingWhitespace = 0d;
             var trailingWhitespaceLength = 0;
@@ -1036,8 +1041,8 @@ namespace Avalonia.Media.TextFormatting
             var lineGap = glyphTypeface.LineGap * scale;
 
             var height = descent - ascent + lineGap;
-         
-            var lineHeight = _paragraphProperties.LineHeight;            
+
+            var lineHeight = _paragraphProperties.LineHeight;
 
             for (var index = 0; index < _textRuns.Count; index++)
             {
@@ -1073,41 +1078,11 @@ namespace Avalonia.Media.TextFormatting
                                 }
                             }
 
-                            switch (_paragraphProperties.FlowDirection)
+                            if (index == _textRuns.Count - 1)
                             {
-                                case FlowDirection.LeftToRight:
-                                    {
-                                        if (index == _textRuns.Count - 1)
-                                        {
-                                            width = widthIncludingWhitespace + textRun.GlyphRun.Metrics.Width;
-                                            trailingWhitespaceLength = textRun.GlyphRun.Metrics.TrailingWhitespaceLength;
-                                            newLineLength = textRun.GlyphRun.Metrics.NewlineLength;
-                                        }
-
-                                        break;
-                                    }
-
-                                case FlowDirection.RightToLeft:
-                                    {
-                                        if (index == _textRuns.Count - 1)
-                                        {
-                                            var firstRun = _textRuns[0];
-
-                                            if (firstRun is ShapedTextCharacters shapedTextCharacters)
-                                            {
-                                                var offset = shapedTextCharacters.GlyphRun.Metrics.WidthIncludingTrailingWhitespace -
-                                                             shapedTextCharacters.GlyphRun.Metrics.Width;
-
-                                                width = widthIncludingWhitespace +
-                                                    textRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace - offset;
-
-                                                trailingWhitespaceLength = shapedTextCharacters.GlyphRun.Metrics.TrailingWhitespaceLength;
-                                                newLineLength = shapedTextCharacters.GlyphRun.Metrics.NewlineLength;
-                                            }
-                                        }
-
-                                        break;
-                                    }
+                                width = widthIncludingWhitespace + textRun.GlyphRun.Metrics.Width;
+                                trailingWhitespaceLength = textRun.GlyphRun.Metrics.TrailingWhitespaceLength;
+                                newLineLength = textRun.GlyphRun.Metrics.NewlineLength;
                             }
 
                             widthIncludingWhitespace += textRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace;
@@ -1166,10 +1141,10 @@ namespace Avalonia.Media.TextFormatting
 
             if (!double.IsNaN(lineHeight) && !MathUtilities.IsZero(lineHeight))
             {
-                if(lineHeight > height)
+                if (lineHeight > height)
                 {
                     height = lineHeight;
-                }              
+                }
             }
 
             return new TextLineMetrics(widthIncludingWhitespace > _paragraphWidth, height, newLineLength, start,

src/Avalonia.Controls/Presenters/TextPresenter.cs

@@ -511,28 +511,39 @@ namespace Avalonia.Controls.Presenters
             
             InvalidateMeasure();
         }
-        
+
+
         protected override Size MeasureOverride(Size availableSize)
         {
+            if (string.IsNullOrEmpty(Text))
+            {
+                return new Size();
+            }
+
             _constraint = availableSize;
-            
+
             _textLayout = null;
-            
+
             InvalidateArrange();
 
-            var measuredSize = PixelSize.FromSize(TextLayout.Bounds.Size, 1);
-            
-            return new Size(measuredSize.Width, measuredSize.Height);
+            var measuredSize = TextLayout.Bounds.Size;
+
+            return measuredSize;
         }
 
         protected override Size ArrangeOverride(Size finalSize)
         {
+            if (finalSize.Width < TextLayout.Bounds.Width)
+            {
+                finalSize = finalSize.WithWidth(TextLayout.Bounds.Width);
+            }
+
             if (MathUtilities.AreClose(_constraint.Width, finalSize.Width))
             {
                 return finalSize;
             }
 
-            _constraint = new Size(finalSize.Width, Math.Ceiling(finalSize.Height));
+            _constraint = new Size(finalSize.Width, double.PositiveInfinity);
 
             _textLayout = null;
 

src/Avalonia.Controls/TextBlock.cs

@@ -604,7 +604,9 @@ namespace Avalonia.Controls
                 return new Size();
             }
 
-            var padding = Padding;
+            var scale = LayoutHelper.GetLayoutScale(this);
+
+            var padding = LayoutHelper.RoundLayoutThickness(Padding, scale, scale);
 
             _constraint = availableSize.Deflate(padding);
 
@@ -612,23 +614,24 @@ namespace Avalonia.Controls
 
             InvalidateArrange();
 
-            var measuredSize = PixelSize.FromSize(TextLayout.Bounds.Size, 1);
+            var measuredSize = TextLayout.Bounds.Size.Inflate(padding);
 
-            return new Size(measuredSize.Width, measuredSize.Height).Inflate(padding);
+            return measuredSize;
         }
 
         protected override Size ArrangeOverride(Size finalSize)
         {
+            if(finalSize.Width < TextLayout.Bounds.Width)
+            {
+                finalSize = finalSize.WithWidth(TextLayout.Bounds.Width);
+            }
+
             if (MathUtilities.AreClose(_constraint.Width, finalSize.Width))
             {
                 return finalSize;
             }
 
-            var padding = Padding;
-
-            var textSize = finalSize.Deflate(padding);
-
-            _constraint = new Size(textSize.Width, Math.Ceiling(textSize.Height));
+            _constraint = new Size(finalSize.Width, double.PositiveInfinity);
 
             _textLayout = null;
 

src/Skia/Avalonia.Skia/TextShaperImpl.cs

@@ -27,7 +27,7 @@ namespace Avalonia.Skia
                 
                 buffer.GuessSegmentProperties();
 
-                buffer.Direction = (bidiLevel & 1) == 0 ? Direction.LeftToRight : Direction.RightToLeft;
+                buffer.Direction = Direction.LeftToRight; //Always shape LeftToRight
 
                 buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);              
 
@@ -35,11 +35,6 @@ 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

@@ -1,6 +1,5 @@
 using System;
 using System.Globalization;
-using Avalonia.Media;
 using Avalonia.Media.TextFormatting;
 using Avalonia.Media.TextFormatting.Unicode;
 using Avalonia.Platform;
@@ -11,8 +10,7 @@ using GlyphInfo = HarfBuzzSharp.GlyphInfo;
 
 namespace Avalonia.Direct2D1.Media
 {
-
-internal class TextShaperImpl : ITextShaperImpl
+    internal class TextShaperImpl : ITextShaperImpl
     {
         public ShapedBuffer ShapeText(ReadOnlySlice<char> text, TextShaperOptions options)
         {
@@ -23,25 +21,20 @@ internal class TextShaperImpl : ITextShaperImpl
 
             using (var buffer = new Buffer())
             {
-                buffer.AddUtf16(text.Buffer.Span, text.Start, text.Length);
+                buffer.AddUtf16(text.Buffer.Span, text.BufferOffset, text.Length);
 
                 MergeBreakPair(buffer);
-                
+
                 buffer.GuessSegmentProperties();
 
-                buffer.Direction = (bidiLevel & 1) == 0 ? Direction.LeftToRight : Direction.RightToLeft;
+                buffer.Direction = Direction.LeftToRight; //Always shape LeftToRight
 
-                buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);              
+                buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);
 
                 var font = ((GlyphTypefaceImpl)typeface.PlatformImpl).Font;
 
                 font.Shape(buffer);
 
-                if (buffer.Direction == Direction.RightToLeft)
-                {
-                    buffer.Reverse();
-                }
-
                 font.GetScale(out var scaleX, out _);
 
                 var textScale = fontRenderingEmSize / scaleX;
@@ -60,13 +53,13 @@ internal class TextShaperImpl : ITextShaperImpl
 
                     var glyphIndex = (ushort)sourceInfo.Codepoint;
 
-                    var glyphCluster = (int)sourceInfo.Cluster;
+                    var glyphCluster = (int)(sourceInfo.Cluster);
 
                     var glyphAdvance = GetGlyphAdvance(glyphPositions, i, textScale);
 
                     var glyphOffset = GetGlyphOffset(glyphPositions, i, textScale);
 
-                    if (glyphIndex == 0 && text[glyphCluster] == '\t')
+                    if (glyphIndex == 0 && text.Buffer.Span[glyphCluster] == '\t')
                     {
                         glyphIndex = typeface.GetGlyph(' ');
 
@@ -75,9 +68,7 @@ internal class TextShaperImpl : ITextShaperImpl
                             4 * typeface.GetGlyphAdvance(glyphIndex) * textScale;
                     }
 
-                    var targetInfo =
-                        new Avalonia.Media.TextFormatting.GlyphInfo(glyphIndex, glyphCluster, glyphAdvance,
-                            glyphOffset);
+                    var targetInfo = new Avalonia.Media.TextFormatting.GlyphInfo(glyphIndex, glyphCluster, glyphAdvance, glyphOffset);
 
                     shapedBuffer[i] = targetInfo;
                 }
@@ -91,7 +82,7 @@ internal class TextShaperImpl : ITextShaperImpl
             var length = buffer.Length;
 
             var glyphInfos = buffer.GetGlyphInfoSpan();
-            
+
             var second = glyphInfos[length - 1];
 
             if (!new Codepoint((int)second.Codepoint).IsBreakChar)
@@ -102,7 +93,7 @@ internal class TextShaperImpl : ITextShaperImpl
             if (length > 1 && glyphInfos[length - 2].Codepoint == '\r' && second.Codepoint == '\n')
             {
                 var first = glyphInfos[length - 2];
-                
+
                 first.Codepoint = '\u200C';
                 second.Codepoint = '\u200C';
                 second.Cluster = first.Cluster;
@@ -113,7 +104,7 @@ internal class TextShaperImpl : ITextShaperImpl
                     {
                         *p = first;
                     }
-                
+
                     fixed (GlyphInfo* p = &glyphInfos[length - 1])
                     {
                         *p = second;
@@ -148,7 +139,7 @@ internal class TextShaperImpl : ITextShaperImpl
         private static double GetGlyphAdvance(ReadOnlySpan<GlyphPosition> glyphPositions, int index, double textScale)
         {
             // Depends on direction of layout
-            // advanceBuffer[index] = buffer.GlyphPositions[index].YAdvance * textScale;
+            // glyphPositions[index].YAdvance * textScale;
             return glyphPositions[index].XAdvance * textScale;
         }
     }