/// <summary>
/// Function to perform word wrapping on a string based on this font.
/// </summary>
/// <param name="text">The text to word wrap.</param>
/// <param name="wordWrapWidth">The maximum width, in pixels, that must be met for word wrapping to occur.</param>
/// <returns>The string with word wrapping.</returns>
/// <remarks>
/// <para>
/// The <paramref name="wordWrapWidth"/> is the maximum number of pixels required for word wrapping, if an individual font glyph cell width (the <see cref="GorgonGlyph.Offset"/> +
/// <see cref="GorgonGlyph.Advance"/>) exceeds that of the <paramref name="wordWrapWidth"/>, then the parameter value is updated to glyph cell width.
/// </para>
/// </remarks>
public string WordWrap(string text, float wordWrapWidth)
{
if (string.IsNullOrEmpty(text))
{
return(text);
}
var wordText = new StringBuilder(text);
if (!Glyphs.TryGetValue(Info.DefaultCharacter, out GorgonGlyph defaultGlyph))
{
throw new GorgonException(GorgonResult.CannotEnumerate, string.Format(Resources.GORGFX_ERR_FONT_DEFAULT_CHAR_NOT_VALID, Info.DefaultCharacter));
}
int maxLength = wordText.Length;
int index = 0;
float position = 0.0f;
bool firstChar = true;
while (index < maxLength)
{
char character = wordText[index];
// Don't count newline or carriage return.
if ((character == '\n') ||
(character == '\r'))
{
firstChar = true;
position = 0;
++index;
continue;
}
if (!Glyphs.TryGetValue(character, out GorgonGlyph glyph))
{
glyph = defaultGlyph;
}
float glyphCellWidth = glyph.Advance;
if (firstChar)
{
glyphCellWidth += glyph.Offset.X;
firstChar = false;
}
// If we're using kerning, then adjust for the kerning value.
if ((Info.UseKerningPairs) &&
(index < maxLength - 1))
{
if (KerningPairs.TryGetValue(new GorgonKerningPair(character, wordText[index + 1]), out int kernValue))
{
glyphCellWidth += kernValue;
}
}
position += glyphCellWidth;
// Update the word wrap boundary if the cell size exceeds it.
if (glyphCellWidth > wordWrapWidth)
{
wordWrapWidth = glyphCellWidth;
}
// We're not at the break yet.
if (position < wordWrapWidth)
{
++index;
continue;
}
int whiteSpaceIndex = index;
// If we hit the max width, then we need to find the previous whitespace and inject a newline.
while ((whiteSpaceIndex <= index) && (whiteSpaceIndex >= 0))
{
char breakChar = wordText[whiteSpaceIndex];
if ((char.IsWhiteSpace(breakChar)) &&
(breakChar != '\n') &&
(breakChar != '\r'))
{
index = whiteSpaceIndex;
break;
}
--whiteSpaceIndex;
}
// If we're at the beginning, then we cannot wrap this text, so we'll break it at the border specified.
if (index != whiteSpaceIndex)
{
if (index != 0)
{
wordText.Insert(index, '\n');
maxLength = wordText.Length;
++index;
}
position = 0;
firstChar = true;
// Move to next character.
++index;
continue;
}
// Extract the space.
wordText[whiteSpaceIndex] = '\n';
position = 0;
firstChar = true;
index = whiteSpaceIndex + 1;
}
return(wordText.ToString());
}
/// <summary>
/// Function to measure the width of an individual line of text.
/// </summary>
/// <param name="line">The line to measure.</param>
/// <param name="useOutline"><b>true</b> to use the font outline, <b>false</b> to disregard it.</param>
/// <returns>The width of the line.</returns>
private float GetLineWidth(string line, bool useOutline)
{
float size = 0;
bool firstChar = true;
if (!Glyphs.TryGetValue(Info.DefaultCharacter, out GorgonGlyph defaultGlyph))
{
throw new GorgonException(GorgonResult.CannotEnumerate, string.Format(Resources.GORGFX_ERR_FONT_DEFAULT_CHAR_NOT_VALID, Info.DefaultCharacter));
}
for (int i = 0; i < line.Length; i++)
{
char character = line[i];
if (!Glyphs.TryGetValue(character, out GorgonGlyph glyph))
{
glyph = defaultGlyph;
}
// Skip out on carriage returns and newlines.
if ((character == '\r') ||
(character == '\n'))
{
continue;
}
// Whitespace will use the glyph width.
if (char.IsWhiteSpace(character))
{
size += glyph.Advance;
continue;
}
// Include the initial offset.
if (firstChar)
{
size += (useOutline && glyph.OutlineCoordinates.Width > 0) ? glyph.OutlineOffset.X : glyph.Offset.X;
firstChar = false;
}
size += glyph.Advance;
if (!Info.UseKerningPairs)
{
continue;
}
if ((i == line.Length - 1) ||
(KerningPairs.Count == 0))
{
continue;
}
var kerning = new GorgonKerningPair(character, line[i + 1]);
if (KerningPairs.TryGetValue(kerning, out int kernAmount))
{
size += kernAmount;
}
}
return(size);
}