private FormattedLine consumeComponents(List <string> components, int startIndex, double desiredWidth, double fontSize)
{
FormattedLine bestResult = null;
int lowCount = 1;
int highCount = components.Count() - startIndex;
while (highCount >= lowCount)
{
int testCount = Math.Min(lowCount * 2, (lowCount + highCount) / 2);
string testText = String.Join("", components.GetRange(startIndex, testCount));
Size requiredSize = this.getLineSize(testText, fontSize);
if (requiredSize.Width <= desiredWidth)
{
// we found some characters that all fit into one line
bestResult = new FormattedLine(testCount, testText, requiredSize);
lowCount = testCount + 1;
}
else
{
// we tried to use too many characters at once, and they didn't all fit
if (bestResult == null)
{
// We can only get here on the first iteration, when measuring only the first word
// If not even the first word fit, then we return it anyway, so the caller knows how much space it needs
bestResult = new FormattedLine(testCount, testText, requiredSize);
}
highCount = testCount - 1;
}
}
return(bestResult);
}
public FormattedParagraph FormatParagraph(String text, double desiredWidth, bool allowSplittingWords, double fontSize)
{
if (text == null || text == "")
{
return(new FormattedParagraph(new Size(), text));
}
// total size of the paragraph
Size totalSize = new Size();
// the unsplittable units that we're going to measure
List <string> components;
int i;
if (allowSplittingWords)
{
components = new List <string>();
for (i = 0; i < text.Length; i++)
{
components.Add(text.Substring(i, 1));
}
}
else
{
string[] words = text.Split(' ');
components = new List <string>();
for (i = 0; i < words.Length; i++)
{
if (i != 0)
{
components.Add(" ");
}
components.Add(words[i]);
}
}
List <string> formattedLines = new List <string>();
i = 0;
while (i < components.Count())
{
// consume as many words as will fit on this line
FormattedLine line = consumeComponents(components, i, desiredWidth, fontSize);
// add new text
formattedLines.Add(line.Text);
// update size
totalSize.Width = Math.Max(totalSize.Width, line.Size.Width);
totalSize.Height += line.Size.Height;
// continue to subsequent components
i += line.NumComponents;
// If a space character wrapped to the next line, we can skip it instead
if (i < components.Count)
{
if (components[i] == " ")
{
i++;
}
}
}
return(new FormattedParagraph(totalSize, String.Join("\n", formattedLines)));
}