/// <summary>
/// Creates the text line metrics.
/// </summary>
/// <param name="textRuns">The text runs.</param>
/// <param name="paragraphWidth">The paragraph width.</param>
/// <param name="textAlignment">The text alignment.</param>
/// <returns></returns>
public static TextLineMetrics Create(IEnumerable <TextRun> textRuns, double paragraphWidth, TextAlignment textAlignment)
{
var lineWidth = 0.0;
var ascent = 0.0;
var descent = 0.0;
var lineGap = 0.0;
foreach (var textRun in textRuns)
{
var shapedRun = (ShapedTextRun)textRun;
lineWidth += shapedRun.Bounds.Width;
var textFormat = textRun.Style.TextFormat;
if (ascent > textRun.Style.TextFormat.FontMetrics.Ascent)
{
ascent = textFormat.FontMetrics.Ascent;
}
if (descent < textFormat.FontMetrics.Descent)
{
descent = textFormat.FontMetrics.Descent;
}
if (lineGap < textFormat.FontMetrics.LineGap)
{
lineGap = textFormat.FontMetrics.LineGap;
}
}
var xOrigin = TextLine.GetParagraphOffsetX(lineWidth, paragraphWidth, textAlignment);
return(new TextLineMetrics(lineWidth, xOrigin, ascent, descent, lineGap));
}
/// <summary>
/// Creates the text line metrics.
/// </summary>
/// <param name="textRuns">The text runs.</param>
/// <param name="textRange">The text range that is covered by the text line.</param>
/// <param name="paragraphWidth">The paragraph width.</param>
/// <param name="paragraphProperties">The text alignment.</param>
/// <returns></returns>
public static TextLineMetrics Create(IEnumerable <TextRun> textRuns, TextRange textRange, double paragraphWidth,
TextParagraphProperties paragraphProperties)
{
var lineWidth = 0.0;
var ascent = 0.0;
var descent = 0.0;
var lineGap = 0.0;
foreach (var textRun in textRuns)
{
var shapedRun = (ShapedTextCharacters)textRun;
var fontMetrics =
new FontMetrics(shapedRun.Properties.Typeface, shapedRun.Properties.FontRenderingEmSize);
lineWidth += shapedRun.Bounds.Width;
if (ascent > fontMetrics.Ascent)
{
ascent = fontMetrics.Ascent;
}
if (descent < fontMetrics.Descent)
{
descent = fontMetrics.Descent;
}
if (lineGap < fontMetrics.LineGap)
{
lineGap = fontMetrics.LineGap;
}
}
var xOrigin = TextLine.GetParagraphOffsetX(lineWidth, paragraphWidth, paragraphProperties.TextAlignment);
var baselineOrigin = new Point(xOrigin, -ascent);
var size = new Size(lineWidth,
double.IsNaN(paragraphProperties.LineHeight) || MathUtilities.IsZero(paragraphProperties.LineHeight) ?
descent - ascent + lineGap :
paragraphProperties.LineHeight);
return(new TextLineMetrics(size, baselineOrigin, textRange));
}
/// <summary>
/// Draws the text layout.
/// </summary>
/// <param name="context">The drawing context.</param>
/// <param name="origin">The origin.</param>
public void Draw(DrawingContext context, Point origin)
{
if (!TextLines.Any())
{
return;
}
var currentY = origin.Y;
foreach (var textLine in TextLines)
{
var offsetX = TextLine.GetParagraphOffsetX(textLine.LineMetrics.Size.Width, Size.Width,
_paragraphProperties.TextAlignment);
textLine.Draw(context, new Point(origin.X + offsetX, currentY));
currentY += textLine.LineMetrics.Size.Height;
}
}
/// <summary>
/// Draws the text layout.
/// </summary>
/// <param name="context">The drawing context.</param>
public void Draw(DrawingContext context)
{
if (!TextLines.Any())
{
return;
}
var currentY = 0.0;
foreach (var textLine in TextLines)
{
var offsetX = TextLine.GetParagraphOffsetX(textLine.LineMetrics.Size.Width, Size.Width,
_paragraphProperties.TextAlignment);
using (context.PushPostTransform(Matrix.CreateTranslation(offsetX, currentY)))
{
textLine.Draw(context);
}
currentY += textLine.LineMetrics.Size.Height;
}
}
