public void Should_Enumerate(string text, int expectedLength)
{
var enumerator = new GraphemeEnumerator(text.AsMemory());
Assert.True(enumerator.MoveNext());
Assert.Equal(expectedLength, enumerator.Current.Text.Length);
}
public void Should_Get_CharacterHit_From_Distance_RTL_With_TextStyles()
{
using (Start())
{
var text = "أَبْجَدِيَّة عَرَبِيَّة";
var i = 0;
var graphemeEnumerator = new GraphemeEnumerator(text.AsMemory());
while (graphemeEnumerator.MoveNext())
{
var grapheme = graphemeEnumerator.Current;
var textStyleOverrides = new[] { new ValueSpan <TextRunProperties>(i, grapheme.Text.Length, new GenericTextRunProperties(Typeface.Default, 12, foregroundBrush: Brushes.Red)) };
i += grapheme.Text.Length;
var layout = new TextLayout(
text,
Typeface.Default,
12,
Brushes.Black,
textStyleOverrides: textStyleOverrides);
var textLine = layout.TextLines[0];
var shapedRuns = textLine.TextRuns.Cast <ShapedTextCharacters>().ToList();
var clusters = shapedRuns.SelectMany(x => x.ShapedBuffer.GlyphClusters).ToList();
var glyphAdvances = shapedRuns.SelectMany(x => x.ShapedBuffer.GlyphAdvances).ToList();
var currentX = 0.0;
var cluster = text.Length;
for (int j = 0; j < clusters.Count - 1; j++)
{
var glyphAdvance = glyphAdvances[j];
var characterHit = textLine.GetCharacterHitFromDistance(currentX);
Assert.Equal(cluster, characterHit.FirstCharacterIndex + characterHit.TrailingLength);
var distance = textLine.GetDistanceFromCharacterHit(new CharacterHit(cluster));
Assert.Equal(currentX, distance, 5);
currentX += glyphAdvance;
cluster = clusters[j];
}
}
}
}
/// <summary>
/// Tries to get a shapeable length that is supported by the specified typeface.
/// </summary>
/// <param name="text">The text.</param>
/// <param name="typeface">The typeface that is used to find matching characters.</param>
/// <param name="defaultTypeface"></param>
/// <param name="length">The shapeable length.</param>
/// <param name="script"></param>
/// <returns></returns>
protected static bool TryGetShapeableLength(
ReadOnlySlice <char> text,
Typeface typeface,
Typeface?defaultTypeface,
out int length,
out Script script)
{
length = 0;
script = Script.Unknown;
if (text.Length == 0)
{
return(false);
}
var font = typeface.GlyphTypeface;
var defaultFont = defaultTypeface?.GlyphTypeface;
var enumerator = new GraphemeEnumerator(text);
while (enumerator.MoveNext())
{
var currentGrapheme = enumerator.Current;
var currentScript = currentGrapheme.FirstCodepoint.Script;
if (currentScript != Script.Common && defaultFont != null && defaultFont.TryGetGlyph(currentGrapheme.FirstCodepoint, out _))
{
break;
}
//Stop at the first missing glyph
if (!currentGrapheme.FirstCodepoint.IsBreakChar && !font.TryGetGlyph(currentGrapheme.FirstCodepoint, out _))
{
break;
}
if (currentScript != script)
{
if (script is Script.Unknown || currentScript != Script.Common &&
script is Script.Common or Script.Inherited)
{
script = currentScript;
}
else
{
if (currentScript != Script.Inherited && currentScript != Script.Common)
{
break;
}
}
}
length += currentGrapheme.Text.Length;
}
/// <summary>
/// Creates a shapeable text run with unique properties.
/// </summary>
/// <param name="text">The text to create text runs from.</param>
/// <param name="defaultProperties">The default text run properties.</param>
/// <returns>A list of shapeable text runs.</returns>
private ShapeableTextCharacters CreateShapeableRun(ReadOnlySlice <char> text, TextRunProperties defaultProperties)
{
var defaultTypeface = defaultProperties.Typeface;
var currentTypeface = defaultTypeface;
if (TryGetRunProperties(text, currentTypeface, defaultTypeface, out var count))
{
return(new ShapeableTextCharacters(text.Take(count),
new GenericTextRunProperties(currentTypeface, defaultProperties.FontRenderingEmSize,
defaultProperties.TextDecorations, defaultProperties.ForegroundBrush)));
}
var codepoint = Codepoint.ReadAt(text, count, out _);
//ToDo: Fix FontFamily fallback
var matchFound =
FontManager.Current.TryMatchCharacter(codepoint, defaultTypeface.Style, defaultTypeface.Weight,
defaultTypeface.FontFamily, defaultProperties.CultureInfo, out currentTypeface);
if (matchFound && TryGetRunProperties(text, currentTypeface, defaultTypeface, out count))
{
//Fallback found
return(new ShapeableTextCharacters(text.Take(count),
new GenericTextRunProperties(currentTypeface, defaultProperties.FontRenderingEmSize,
defaultProperties.TextDecorations, defaultProperties.ForegroundBrush)));
}
// no fallback found
currentTypeface = defaultTypeface;
var glyphTypeface = currentTypeface.GlyphTypeface;
var enumerator = new GraphemeEnumerator(text);
while (enumerator.MoveNext())
{
var grapheme = enumerator.Current;
if (!grapheme.FirstCodepoint.IsWhiteSpace && glyphTypeface.TryGetGlyph(grapheme.FirstCodepoint, out _))
{
break;
}
count += grapheme.Text.Length;
}
return(new ShapeableTextCharacters(text.Take(count),
new GenericTextRunProperties(currentTypeface, defaultProperties.FontRenderingEmSize,
defaultProperties.TextDecorations, defaultProperties.ForegroundBrush)));
}
/// <summary>
/// Creates a text style run with unique properties.
/// </summary>
/// <param name="text">The text to create text runs from.</param>
/// <param name="defaultStyle"></param>
/// <returns>A list of text runs.</returns>
protected TextStyleRun CreateShapableTextStyleRun(ReadOnlySlice <char> text, TextStyle defaultStyle)
{
var defaultTypeface = defaultStyle.TextFormat.Typeface;
var currentTypeface = defaultTypeface;
if (TryGetRunProperties(text, currentTypeface, defaultTypeface, out var count))
{
return(new TextStyleRun(new TextPointer(text.Start, count), new TextStyle(currentTypeface,
defaultStyle.TextFormat.FontRenderingEmSize,
defaultStyle.Foreground, defaultStyle.TextDecorations)));
}
var codepoint = Codepoint.ReadAt(text, count, out _);
//ToDo: Fix FontFamily fallback
currentTypeface =
FontManager.Current.MatchCharacter(codepoint, defaultTypeface.Weight, defaultTypeface.Style);
if (currentTypeface != null && TryGetRunProperties(text, currentTypeface, defaultTypeface, out count))
{
//Fallback found
return(new TextStyleRun(new TextPointer(text.Start, count), new TextStyle(currentTypeface,
defaultStyle.TextFormat.FontRenderingEmSize,
defaultStyle.Foreground, defaultStyle.TextDecorations)));
}
// no fallback found
currentTypeface = defaultTypeface;
var glyphTypeface = currentTypeface.GlyphTypeface;
var enumerator = new GraphemeEnumerator(text);
while (enumerator.MoveNext())
{
var grapheme = enumerator.Current;
if (!grapheme.FirstCodepoint.IsWhiteSpace && glyphTypeface.TryGetGlyph(grapheme.FirstCodepoint, out _))
{
break;
}
count += grapheme.Text.Length;
}
return(new TextStyleRun(new TextPointer(text.Start, count),
new TextStyle(currentTypeface, defaultStyle.TextFormat.FontRenderingEmSize,
defaultStyle.Foreground, defaultStyle.TextDecorations)));
}
private bool Run(GraphemeBreakData t)
{
var text = Encoding.UTF32.GetString(MemoryMarshal.Cast <int, byte>(t.Codepoints).ToArray());
var grapheme = Encoding.UTF32.GetString(MemoryMarshal.Cast <int, byte>(t.Grapheme).ToArray()).AsSpan();
var enumerator = new GraphemeEnumerator(text.AsMemory());
enumerator.MoveNext();
var actual = enumerator.Current.Text.Span;
var pass = true;
if (actual.Length != grapheme.Length)
{
pass = false;
}
if (pass)
{
for (int i = 0; i < grapheme.Length; i++)
{
var a = grapheme[i];
var b = actual[i];
if (a != b)
{
pass = false;
break;
}
}
}
if (!pass)
{
_outputHelper.WriteLine($"Failed line {t.LineNumber}");
_outputHelper.WriteLine($" Text: {text}");
_outputHelper.WriteLine($" Codepoints: {string.Join(" ", t.Codepoints)}");
_outputHelper.WriteLine($" Grapheme: {string.Join(" ", t.Grapheme)}");
_outputHelper.WriteLine($" Line: {t.Line}");
return(false);
}
return(true);
}
public void Should_Enumerate_Other()
{
const string text = "ABCDEFGHIJ";
var enumerator = new GraphemeEnumerator(text.AsMemory());
var count = 0;
while (enumerator.MoveNext())
{
Assert.Equal(1, enumerator.Current.Text.Length);
count++;
}
Assert.Equal(10, count);
}
private static int CoerceLength(ReadOnlySlice <char> text, int length)
{
var finalLength = 0;
var graphemeEnumerator = new GraphemeEnumerator(text);
while (graphemeEnumerator.MoveNext())
{
var grapheme = graphemeEnumerator.Current;
finalLength += grapheme.Text.Length;
if (finalLength >= length)
{
return(finalLength);
}
}
return(length);
}
/// <summary>
/// Tries to get run properties.
/// </summary>
/// <param name="defaultTypeface"></param>
/// <param name="text"></param>
/// <param name="typeface">The typeface that is used to find matching characters.</param>
/// <param name="count"></param>
/// <returns></returns>
protected bool TryGetRunProperties(ReadOnlySlice <char> text, Typeface typeface, Typeface defaultTypeface,
out int count)
{
if (text.Length == 0)
{
count = 0;
return(false);
}
var isFallback = typeface != defaultTypeface;
count = 0;
var script = Script.Common;
//var direction = BiDiClass.LeftToRight;
var font = typeface.GlyphTypeface;
var defaultFont = defaultTypeface.GlyphTypeface;
var enumerator = new GraphemeEnumerator(text);
while (enumerator.MoveNext())
{
var grapheme = enumerator.Current;
var currentScript = grapheme.FirstCodepoint.Script;
//var currentDirection = grapheme.FirstCodepoint.BiDiClass;
//// ToDo: Implement BiDi algorithm
//if (currentScript.HorizontalDirection != direction)
//{
// if (!UnicodeUtility.IsWhiteSpace(grapheme.FirstCodepoint))
// {
// break;
// }
//}
if (currentScript != script)
{
if (currentScript != Script.Inherited && currentScript != Script.Common)
{
if (script == Script.Inherited || script == Script.Common)
{
script = currentScript;
}
else
{
break;
}
}
}
if (isFallback)
{
if (defaultFont.TryGetGlyph(grapheme.FirstCodepoint, out _))
{
break;
}
}
if (!font.TryGetGlyph(grapheme.FirstCodepoint, out _))
{
if (!grapheme.FirstCodepoint.IsWhiteSpace)
{
break;
}
}
count += grapheme.Text.Length;
}
return(count > 0);
}
public void Should_Not_Alter_Lines_After_TextStyleSpan_Was_Applied()
{
using (Start())
{
const string text = "אחד !\ntwo !\nשְׁלוֹשָׁה !";
var red = new SolidColorBrush(Colors.Red).ToImmutable();
var black = Brushes.Black.ToImmutable();
var expected = new TextLayout(
text,
Typeface.Default,
12.0f,
black,
textWrapping: TextWrapping.Wrap);
var expectedGlyphs = expected.TextLines.Select(x => string.Join('|', x.TextRuns.Cast <ShapedTextCharacters>()
.SelectMany(x => x.ShapedBuffer.GlyphIndices))).ToList();
var outer = new GraphemeEnumerator(text.AsMemory());
var inner = new GraphemeEnumerator(text.AsMemory());
var i = 0;
var j = 0;
while (true)
{
while (inner.MoveNext())
{
j += inner.Current.Text.Length;
if (j + i > text.Length)
{
break;
}
var spans = new[]
{
new ValueSpan <TextRunProperties>(i, j,
new GenericTextRunProperties(Typeface.Default, 12, foregroundBrush: red))
};
var actual = new TextLayout(
text,
Typeface.Default,
12.0f,
black,
textWrapping: TextWrapping.Wrap,
textStyleOverrides: spans);
var actualGlyphs = actual.TextLines.Select(x => string.Join('|', x.TextRuns.Cast <ShapedTextCharacters>()
.SelectMany(x => x.ShapedBuffer.GlyphIndices))).ToList();
Assert.Equal(expectedGlyphs.Count, actualGlyphs.Count);
for (var k = 0; k < expectedGlyphs.Count; k++)
{
Assert.Equal(expectedGlyphs[k], actualGlyphs[k]);
}
}
if (!outer.MoveNext())
{
break;
}
inner = new GraphemeEnumerator(text.AsMemory());
i += outer.Current.Text.Length;
}
}
}
/// <summary>
/// Creates a shapeable text run with unique properties.
/// </summary>
/// <param name="text">The text to create text runs from.</param>
/// <param name="defaultProperties">The default text run properties.</param>
/// <param name="biDiLevel">The bidi level of the run.</param>
/// <param name="previousProperties"></param>
/// <returns>A list of shapeable text runs.</returns>
private static ShapeableTextCharacters CreateShapeableRun(ReadOnlySlice <char> text,
TextRunProperties defaultProperties, sbyte biDiLevel, ref TextRunProperties?previousProperties)
{
var defaultTypeface = defaultProperties.Typeface;
var currentTypeface = defaultTypeface;
var previousTypeface = previousProperties?.Typeface;
if (TryGetShapeableLength(text, currentTypeface, null, out var count, out var script))
{
if (script == Script.Common && previousTypeface is not null)
{
if (TryGetShapeableLength(text, previousTypeface.Value, defaultTypeface, out var fallbackCount, out _))
{
return(new ShapeableTextCharacters(text.Take(fallbackCount),
defaultProperties.WithTypeface(previousTypeface.Value), biDiLevel));
}
}
return(new ShapeableTextCharacters(text.Take(count), defaultProperties.WithTypeface(currentTypeface),
biDiLevel));
}
if (previousTypeface is not null)
{
if (TryGetShapeableLength(text, previousTypeface.Value, defaultTypeface, out count, out _))
{
return(new ShapeableTextCharacters(text.Take(count),
defaultProperties.WithTypeface(previousTypeface.Value), biDiLevel));
}
}
var codepoint = Codepoint.ReplacementCodepoint;
var codepointEnumerator = new CodepointEnumerator(text.Skip(count));
while (codepointEnumerator.MoveNext())
{
if (codepointEnumerator.Current.IsWhiteSpace)
{
continue;
}
codepoint = codepointEnumerator.Current;
break;
}
//ToDo: Fix FontFamily fallback
var matchFound =
FontManager.Current.TryMatchCharacter(codepoint, defaultTypeface.Style, defaultTypeface.Weight,
defaultTypeface.Stretch, defaultTypeface.FontFamily, defaultProperties.CultureInfo,
out currentTypeface);
if (matchFound && TryGetShapeableLength(text, currentTypeface, defaultTypeface, out count, out _))
{
//Fallback found
return(new ShapeableTextCharacters(text.Take(count), defaultProperties.WithTypeface(currentTypeface),
biDiLevel));
}
// no fallback found
currentTypeface = defaultTypeface;
var glyphTypeface = currentTypeface.GlyphTypeface;
var enumerator = new GraphemeEnumerator(text);
while (enumerator.MoveNext())
{
var grapheme = enumerator.Current;
if (!grapheme.FirstCodepoint.IsWhiteSpace && glyphTypeface.TryGetGlyph(grapheme.FirstCodepoint, out _))
{
break;
}
count += grapheme.Text.Length;
}
return(new ShapeableTextCharacters(text.Take(count), defaultProperties, biDiLevel));
}
/// <summary>
/// Tries to get run properties.
/// </summary>
/// <param name="defaultTypeface"></param>
/// <param name="text"></param>
/// <param name="typeface">The typeface that is used to find matching characters.</param>
/// <param name="count"></param>
/// <returns></returns>
protected bool TryGetRunProperties(ReadOnlySlice <char> text, Typeface typeface, Typeface defaultTypeface,
out int count)
{
if (text.Length == 0)
{
count = 0;
return(false);
}
var isFallback = typeface != defaultTypeface;
count = 0;
var script = Script.Unknown;
var direction = BiDiClass.LeftToRight;
var font = typeface.GlyphTypeface;
var defaultFont = defaultTypeface.GlyphTypeface;
var enumerator = new GraphemeEnumerator(text);
while (enumerator.MoveNext())
{
var currentGrapheme = enumerator.Current;
var currentScript = currentGrapheme.FirstCodepoint.Script;
var currentDirection = currentGrapheme.FirstCodepoint.BiDiClass;
//// ToDo: Implement BiDi algorithm
//if (currentScript.HorizontalDirection != direction)
//{
// if (!UnicodeUtility.IsWhiteSpace(grapheme.FirstCodepoint))
// {
// break;
// }
//}
if (currentScript != script)
{
if (script is Script.Unknown)
{
script = currentScript;
}
else
{
if (currentScript != Script.Inherited && currentScript != Script.Common)
{
break;
}
}
}
//Only handle non whitespace here
if (!currentGrapheme.FirstCodepoint.IsWhiteSpace)
{
//Stop at the first glyph that is present in the default typeface.
if (isFallback && defaultFont.TryGetGlyph(currentGrapheme.FirstCodepoint, out _))
{
break;
}
//Stop at the first missing glyph
if (!font.TryGetGlyph(currentGrapheme.FirstCodepoint, out _))
{
break;
}
}
if (!currentGrapheme.FirstCodepoint.IsWhiteSpace && !font.TryGetGlyph(currentGrapheme.FirstCodepoint, out _))
{
break;
}
if (direction == BiDiClass.RightToLeft && currentDirection == BiDiClass.CommonSeparator)
{
break;
}
count += currentGrapheme.Text.Length;
direction = currentDirection;
}
return(count > 0);
}