/// <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)));
}
public void Should_Take()
{
var buffer = new[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
var slice = new ReadOnlySlice <int>(buffer);
var taken = slice.Take(8);
var expected = buffer.Take(8);
Assert.Equal(expected, taken);
}
/// <summary>
/// Creates a span of text run properties that has modifier applied.
/// </summary>
/// <param name="text">The text to create the properties for.</param>
/// <param name="defaultProperties">The default text properties.</param>
/// <param name="textModifier">The text properties modifier.</param>
/// <returns>
/// The created text style run.
/// </returns>
private static ValueSpan <TextRunProperties> CreateTextStyleRun(ReadOnlySlice <char> text,
TextRunProperties defaultProperties, IReadOnlyList <ValueSpan <TextRunProperties> > textModifier)
{
if (textModifier == null || textModifier.Count == 0)
{
return(new ValueSpan <TextRunProperties>(text.Start, text.Length, defaultProperties));
}
var currentProperties = defaultProperties;
var hasOverride = false;
var i = 0;
var length = 0;
for (; i < textModifier.Count; i++)
{
var propertiesOverride = textModifier[i];
var textRange = new TextRange(propertiesOverride.Start, propertiesOverride.Length);
if (textRange.End < text.Start)
{
continue;
}
if (textRange.Start > text.End)
{
length = text.Length;
break;
}
if (textRange.Start > text.Start)
{
if (propertiesOverride.Value != currentProperties)
{
length = Math.Min(Math.Abs(textRange.Start - text.Start), text.Length);
break;
}
}
length += Math.Min(text.Length - length, textRange.Length);
if (hasOverride)
{
continue;
}
hasOverride = true;
currentProperties = propertiesOverride.Value;
}
if (length < text.Length && i == textModifier.Count)
{
if (currentProperties == defaultProperties)
{
length = text.Length;
}
}
if (length != text.Length)
{
text = text.Take(length);
}
return(new ValueSpan <TextRunProperties>(text.Start, length, currentProperties));
}
/// <summary>
/// Creates a text style run that has overrides applied. Only overrides with equal TextStyle.
/// If optimizeForShaping is <c>true</c> Foreground is ignored.
/// </summary>
/// <param name="text">The text to create the run for.</param>
/// <param name="defaultTextStyle">The default text style for segments that don't have an override.</param>
/// <param name="textStyleOverrides">The text style overrides.</param>
/// <returns>
/// The created text style run.
/// </returns>
private static TextStyleRun CreateTextStyleRunWithOverride(ReadOnlySlice <char> text,
TextStyle defaultTextStyle, IReadOnlyList <TextStyleRun> textStyleOverrides)
{
if (textStyleOverrides == null || textStyleOverrides.Count == 0)
{
return(new TextStyleRun(new TextPointer(text.Start, text.Length), defaultTextStyle));
}
var currentTextStyle = defaultTextStyle;
var hasOverride = false;
var i = 0;
var length = 0;
for (; i < textStyleOverrides.Count; i++)
{
var styleOverride = textStyleOverrides[i];
var textPointer = styleOverride.TextPointer;
if (textPointer.End < text.Start)
{
continue;
}
if (textPointer.Start > text.End)
{
length = text.Length;
break;
}
if (textPointer.Start > text.Start)
{
if (styleOverride.Style.TextFormat != currentTextStyle.TextFormat ||
!currentTextStyle.Foreground.Equals(styleOverride.Style.Foreground))
{
length = Math.Min(Math.Abs(textPointer.Start - text.Start), text.Length);
break;
}
}
length += Math.Min(text.Length - length, textPointer.Length);
if (hasOverride)
{
continue;
}
hasOverride = true;
currentTextStyle = styleOverride.Style;
}
if (length < text.Length && i == textStyleOverrides.Count)
{
if (currentTextStyle.Foreground.Equals(defaultTextStyle.Foreground) &&
currentTextStyle.TextFormat == defaultTextStyle.TextFormat)
{
length = text.Length;
}
}
if (length != text.Length)
{
text = text.Take(length);
}
return(new TextStyleRun(new TextPointer(text.Start, length), currentTextStyle));
}
/// <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));
}
