// ------------------------------------------------------------------
// Dump text paragraph result.
// ------------------------------------------------------------------
private static void DumpTextParagraphResult(XmlTextWriter writer, TextParagraphResult paragraph, Visual visualParent)
{
writer.WriteStartElement("TextParagraph");
// Dump paragraph info
writer.WriteStartElement("Element");
writer.WriteAttributeString("Type", paragraph.Element.GetType().FullName);
writer.WriteEndElement();
DumpRect(writer, "LayoutBox", paragraph.LayoutBox);
Visual visual = DumpParagraphOffset(writer, paragraph, visualParent);
DumpTextRange(writer, paragraph.StartPosition, paragraph.EndPosition);
DumpLineResults(writer, paragraph.Lines, visual);
DumpParagraphResults(writer, "Floaters", paragraph.Floaters, visual);
DumpParagraphResults(writer, "Figures", paragraph.Figures, visual);
writer.WriteEndElement();
}
/// <summary>
/// Retrieves an oriented text position advancing by number of lines from its initial position.
/// </summary>
/// <param name="paragraph">Text paragraph.</param>
/// <param name="suggestedX">
/// The suggested X offset, in pixels, of text position on the destination
/// line. If suggestedX is set to Double.NaN it will be ignored, otherwise
/// the method will try to find a position on the destination line closest
/// to suggestedX.
/// </param>
/// <param name="count">Number of lines to advance. Negative means move backwards.</param>
/// <returns>
/// A TextPointer and its orientation matching suggestedX on the
/// destination line.
/// </returns>
private ITextPointer GetPositionAtNextLineFromSiblingTextPara(TextParagraphResult paragraph, double suggestedX, ref int count)
{
ITextPointer positionOut = null;
// TextParagraph - start from the first or last line (depending on the count
// value sign) and find the previous/next line in the line array.
// If new line (specified by count) is not in the range of this TextParagraph,
// update count value by the line count.
ReadOnlyCollection<LineResult> lines = paragraph.Lines;
Invariant.Assert(lines != null, "Lines collection is null");
if (!paragraph.HasTextContent)
{
// Paragraph has no text content, which means it either has no lines at all or just figures and floaters.
// In either case, we cannot step into it from GetPositionAtNextLine. We must set positionOut to null and
// try to advance elsewhere.
positionOut = null;
}
else
{
Rect paragraphBox = paragraph.LayoutBox;
// We are entering this paragraph. Get index of the first/last line
// (depending on the sing of count value) and try to find out line index.
int lineIndex = (count > 0) ? 0 : lines.Count - 1;
// We are about to analyze the first/last line in the paragraph, so adjust the
// count to take it into account.
if (count < 0)
{
++count;
}
else
{
--count;
}
// If the new line is not in the range of this paragraph , change the count
// value by the number of lines in the paragraph.
if (lineIndex + count < 0)
{
count += lineIndex;
}
else if (lineIndex + count > lines.Count - 1)
{
count -= (lines.Count - 1 - lineIndex);
}
else
{
lineIndex = lineIndex + count;
count = 0;
}
// If count is 0, the new line is in this paragraph
if (count == 0)
{
// Get position at suggested X. If suggested X is not provided,
// use the first position in the line.
if (!DoubleUtil.IsNaN(suggestedX))
{
positionOut = lines[lineIndex].GetTextPositionFromDistance(suggestedX);
}
else
{
positionOut = lines[lineIndex].StartPosition.CreatePointer(LogicalDirection.Forward);
}
}
else
{
// If count is not 0, the new line is in the next/previous paragraph.
if (count < 0)
{
// Just in case there are no lines above, set position to the first line.
if (!DoubleUtil.IsNaN(suggestedX))
{
positionOut = lines[0].GetTextPositionFromDistance(suggestedX);
}
else
{
positionOut = lines[0].StartPosition.CreatePointer(LogicalDirection.Forward);
}
}
else
{
// Just in case there are no lines below, set position to the last line.
if (!DoubleUtil.IsNaN(suggestedX))
{
positionOut = lines[lines.Count - 1].GetTextPositionFromDistance(suggestedX);
}
else
{
positionOut = lines[lines.Count - 1].StartPosition.CreatePointer(LogicalDirection.Forward);
}
}
}
}
return positionOut;
}
