private TextLineMetrics CreateLineMetrics()
{
var width = 0d;
var widthIncludingWhitespace = 0d;
var trailingWhitespaceLength = 0;
var newLineLength = 0;
var ascent = 0d;
var descent = 0d;
var lineGap = 0d;
var fontRenderingEmSize = 0d;
for (var index = 0; index < _textRuns.Count; index++)
{
var textRun = _textRuns[index];
var fontMetrics =
new FontMetrics(textRun.Properties.Typeface, textRun.Properties.FontRenderingEmSize);
if (fontRenderingEmSize < textRun.Properties.FontRenderingEmSize)
{
fontRenderingEmSize = textRun.Properties.FontRenderingEmSize;
if (ascent > fontMetrics.Ascent)
{
ascent = fontMetrics.Ascent;
}
if (descent < fontMetrics.Descent)
{
descent = fontMetrics.Descent;
}
if (lineGap < fontMetrics.LineGap)
{
lineGap = fontMetrics.LineGap;
}
}
switch (_paragraphProperties.FlowDirection)
{
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];
var offset = firstRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace -
firstRun.GlyphRun.Metrics.Width;
width = widthIncludingWhitespace +
textRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace - offset;
trailingWhitespaceLength = firstRun.GlyphRun.Metrics.TrailingWhitespaceLength;
newLineLength = firstRun.GlyphRun.Metrics.NewlineLength;
}
break;
}
}
widthIncludingWhitespace += textRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace;
}
var start = GetParagraphOffsetX(width, widthIncludingWhitespace, _paragraphWidth,
_paragraphProperties.TextAlignment, _paragraphProperties.FlowDirection);
var lineHeight = _paragraphProperties.LineHeight;
var height = double.IsNaN(lineHeight) || MathUtilities.IsZero(lineHeight) ?
descent - ascent + lineGap :
lineHeight;
return(new TextLineMetrics(widthIncludingWhitespace > _paragraphWidth, height, newLineLength, start,
-ascent, trailingWhitespaceLength, width, widthIncludingWhitespace));
}
private TextLineMetrics CreateLineMetrics()
{
var start = 0d;
var height = 0d;
var width = 0d;
var widthIncludingWhitespace = 0d;
var trailingWhitespaceLength = 0;
var newLineLength = 0;
var ascent = 0d;
var descent = 0d;
var lineGap = 0d;
var fontRenderingEmSize = 0d;
var lineHeight = _paragraphProperties.LineHeight;
if (_textRuns.Count == 0)
{
var glyphTypeface = _paragraphProperties.DefaultTextRunProperties.Typeface.GlyphTypeface;
fontRenderingEmSize = _paragraphProperties.DefaultTextRunProperties.FontRenderingEmSize;
var scale = fontRenderingEmSize / glyphTypeface.DesignEmHeight;
ascent = glyphTypeface.Ascent * scale;
height = double.IsNaN(lineHeight) || MathUtilities.IsZero(lineHeight) ?
descent - ascent + lineGap :
lineHeight;
return(new TextLineMetrics(false, height, 0, start, -ascent, 0, 0, 0));
}
for (var index = 0; index < _textRuns.Count; index++)
{
switch (_textRuns[index])
{
case ShapedTextCharacters textRun:
{
var fontMetrics =
new FontMetrics(textRun.Properties.Typeface, textRun.Properties.FontRenderingEmSize);
if (fontRenderingEmSize < textRun.Properties.FontRenderingEmSize)
{
fontRenderingEmSize = textRun.Properties.FontRenderingEmSize;
if (ascent > fontMetrics.Ascent)
{
ascent = fontMetrics.Ascent;
}
if (descent < fontMetrics.Descent)
{
descent = fontMetrics.Descent;
}
if (lineGap < fontMetrics.LineGap)
{
lineGap = fontMetrics.LineGap;
}
if (descent - ascent + lineGap > height)
{
height = descent - ascent + lineGap;
}
}
switch (_paragraphProperties.FlowDirection)
{
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;
}
}
widthIncludingWhitespace += textRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace;
break;
}
case { } drawableTextRun:
{
widthIncludingWhitespace += drawableTextRun.Size.Width;
switch (_paragraphProperties.FlowDirection)
{
case FlowDirection.LeftToRight:
{
if (index == _textRuns.Count - 1)
{
width = widthIncludingWhitespace;
trailingWhitespaceLength = 0;
newLineLength = 0;
}
break;
}
case FlowDirection.RightToLeft:
{
if (index == _textRuns.Count - 1)
{
width = widthIncludingWhitespace;
trailingWhitespaceLength = 0;
newLineLength = 0;
}
break;
}
}
if (drawableTextRun.Size.Height > height)
{
height = drawableTextRun.Size.Height;
}
if (ascent > -drawableTextRun.Baseline)
{
ascent = -drawableTextRun.Baseline;
}
break;
}
}
}
start = GetParagraphOffsetX(width, widthIncludingWhitespace, _paragraphWidth,
_paragraphProperties.TextAlignment, _paragraphProperties.FlowDirection);
if (!double.IsNaN(lineHeight) && !MathUtilities.IsZero(lineHeight))
{
height = lineHeight;
}
return(new TextLineMetrics(widthIncludingWhitespace > _paragraphWidth, height, newLineLength, start,
-ascent, trailingWhitespaceLength, width, widthIncludingWhitespace));
}
public TextFormat(Typeface typeface, double fontRenderingEmSize)
{
Typeface = typeface;
FontRenderingEmSize = fontRenderingEmSize;
FontMetrics = new FontMetrics(typeface, fontRenderingEmSize);
}