private void ReverseCharacterPositions(int index1, int index2)
{
DocumentCharacterPositions tempPos = _characters[index1].Positions;
DocumentCharacter tempCharacter = _characters[index1];
tempCharacter.Positions = _characters[index2].Positions;
_characters[index1] = tempCharacter;
tempCharacter = _characters[index2];
tempCharacter.Positions = tempPos;
_characters[index2] = tempCharacter;
}
public static DocumentText FromSvgDocument(SvgDocument document)
{
// Out list of charcaters
var characters = new List <DocumentCharacter>();
// To strip whitespaces
var hasWhitespaces = false;
var prevCharacter = new DocumentCharacter();
// Callback
SvgSortElementsCallback sortCallback = (callabackDocument, info, userData) =>
{
// Is it text?
var textData = info.TextData;
if (textData != null)
{
// yes, does it have any characters?
var length = textData.Text.Length;
for (var i = 0; i < length; i++)
{
// Yes, convert to DocumentCharacter and add them to the list
var flags = textData.CharacterFlags[i];
var positions = DocumentCharacterPositions.None;
if ((flags & SvgTextCharacterFlags.EndOfWord) == SvgTextCharacterFlags.EndOfWord)
{
positions |= DocumentCharacterPositions.EndOfWord;
}
if ((flags & SvgTextCharacterFlags.EndOfLine) == SvgTextCharacterFlags.EndOfLine)
{
positions |= DocumentCharacterPositions.EndOfLine;
}
var character = new DocumentCharacter
{
Code = textData.Text[i],
Bounds = textData.Bounds[i],
Positions = positions,
Direction = textData.Directions[i]
};
// If the character duplicated, then remove the old one
if (prevCharacter.Bounds == character.Bounds &&
prevCharacter.Code == character.Code &&
prevCharacter.Direction == character.Direction)
{
characters.Remove(prevCharacter);
}
characters.Add(character);
if (!hasWhitespaces && Char.IsWhiteSpace(character.Code))
{
hasWhitespaces = true;
}
prevCharacter = character;
}
}
return(true);
};
// Accept text elements only.
SvgFilterElementsCallback filterElementsCallback = (svgDocument, nodeHandle, userData) =>
{
// Accept text elements only.
if (nodeHandle.ElementType != SvgElementType.Text)
{
return(false);
}
return(true);
};
// Setup options and sort
var options = new SvgSortOptions {
ExtractText = SvgExtractText.Character, SortFlags = SvgSortFlags.Default
};
document.SetFilterElementsCallback(filterElementsCallback, null);
document.SortElements(options, sortCallback, null);
document.SetFilterElementsCallback(null, null);
// Characters is set, before using it, strip the whitespaces
if (hasWhitespaces)
{
var temp = new List <DocumentCharacter>();
var count = characters.Count;
var positions = DocumentCharacterPositions.None;
var newIndex = -1;
for (var index = 0; index < count; index++)
{
var character = characters[index];
// If this character is a whitespace, dont add it, just steal its position and add it to the previous character
if (Char.IsWhiteSpace(character.Code))
{
positions |= character.Positions;
}
else
{
// If have stolen flags from dropping white space characters, add them to the last non-white space character
if (positions != DocumentCharacterPositions.None)
{
if (newIndex != -1)
{
var tempCharacter = temp[newIndex];
tempCharacter.Positions |= positions;
temp[newIndex] = tempCharacter;
}
positions = DocumentCharacterPositions.None;
}
// Add it
temp.Add(character);
newIndex++;
}
}
characters = temp;
}
var result = new DocumentText(characters);
return(result);
}
public void BuildWords()
{
var characterIndex = 0;
var characterCount = _characters.Count;
var words = new List <DocumentWord>();
var lastReverseWord = false;
var startReverseIndex = -1;
// Loop through all the characters
while (characterIndex < characterCount)
{
// Find the total bounding rectangle, begin and end index of the next word
var wordBounds = LeadRectD.Empty;
var beginCharacterIndex = characterIndex;
bool reverseWord = false;
// Loop till we reach the EndOfWord of EndOfLine
var more = true;
var character = new DocumentCharacter();
while (more && characterIndex < characterCount)
{
character = _characters[characterIndex];
// Add the bounding rectangle of this character
var characterBounds = character.Bounds;
if (wordBounds.IsEmpty)
{
wordBounds = characterBounds;
}
else
{
wordBounds = LeadRectD.UnionRects(wordBounds, characterBounds);
}
more = characterIndex < characterCount &&
(character.Positions & DocumentCharacterPositions.EndOfWord) != DocumentCharacterPositions.EndOfWord &&
(character.Positions & DocumentCharacterPositions.EndOfLine) != DocumentCharacterPositions.EndOfLine;
characterIndex++;
if (character.Direction == SvgCharacterDirection.RightToLeft)
{
reverseWord = true;
}
}
// From the begin and end index, collect the characters into a string
var sb = new StringBuilder();
for (var i = beginCharacterIndex; i < characterIndex; i++)
{
sb.Append(_characters[i].Code);
}
var word = new DocumentWord();
word.Value = sb.ToString();
word.Bounds = wordBounds;
word.FirstCharacterIndex = beginCharacterIndex;
word.LastCharacterIndex = characterIndex - 1;
if (reverseWord)
{
char[] charArray = word.Value.ToCharArray();
int startIndex = 0;
for (int i = 0; i < charArray.Length; i++)
{
int nextIndex = i + 1;
if (_characters[i + word.FirstCharacterIndex].Direction == SvgCharacterDirection.RightToLeft &&
(nextIndex >= charArray.Length ||
_characters[nextIndex + word.FirstCharacterIndex].Direction == SvgCharacterDirection.LeftToRight))
{
Array.Reverse(charArray, startIndex, nextIndex - startIndex);
startIndex = i;
}
}
word.Value = new string(charArray);
}
if (lastReverseWord && reverseWord)
{
startReverseIndex = startReverseIndex == -1 ? words.Count - 1: startReverseIndex;
words.Insert(startReverseIndex, word);
}
else
{
if (startReverseIndex != -1)
{
ReverseCharacterPositions(words[startReverseIndex].LastCharacterIndex, words[words.Count - 1].LastCharacterIndex);
startReverseIndex = -1;
}
words.Add(word);
}
lastReverseWord = reverseWord && (character.Positions & DocumentCharacterPositions.EndOfLine) != DocumentCharacterPositions.EndOfLine;
}
if (startReverseIndex != -1)
{
ReverseCharacterPositions(words[startReverseIndex].LastCharacterIndex, words[words.Count - 1].LastCharacterIndex);
}
_words = words;
}
