/**
* Determines if a space character should be inserted between a previous chunk and the current chunk.
* This method is exposed as a callback so subclasses can fine time the algorithm for determining whether a space should be inserted or not.
* By default, this method will insert a space if the there is a gap of more than half the font space character width between the end of the
* previous chunk and the beginning of the current chunk. It will also indicate that a space is needed if the starting point of the new chunk
* appears *before* the end of the previous chunk (i.e. overlapping text).
* @param chunk the new chunk being evaluated
* @param previousChunk the chunk that appeared immediately before the current chunk
* @return true if the two chunks represent different words (i.e. should have a space between them). False otherwise.
*/
virtual protected bool IsChunkAtWordBoundary(TextChunk chunk, TextChunk previousChunk)
{
float dist = chunk.DistanceFromEndOf(previousChunk);
if (dist < -chunk.CharSpaceWidth || dist > chunk.CharSpaceWidth / 2.0f)
{
return(true);
}
return(false);
}
/**
* Determines if a space character should be inserted between a previous chunk and the current chunk.
* This method is exposed as a callback so subclasses can fine time the algorithm for determining whether a space should be inserted or not.
* By default, this method will insert a space if the there is a gap of more than half the font space character width between the end of the
* previous chunk and the beginning of the current chunk. It will also indicate that a space is needed if the starting point of the new chunk
* appears *before* the end of the previous chunk (i.e. overlapping text).
* @param chunk the new chunk being evaluated
* @param previousChunk the chunk that appeared immediately before the current chunk
* @return true if the two chunks represent different words (i.e. should have a space between them). False otherwise.
*/
virtual protected bool IsChunkAtWordBoundary(TextChunk chunk, TextChunk previousChunk)
{
/**
* Here we handle a very specific case which in PDF may look like:
* -.232 Tc [( P)-226.2(r)-231.8(e)-230.8(f)-238(a)-238.9(c)-228.9(e)]TJ
* The font's charSpace width is 0.232 and it's compensated with charSpacing of 0.232.
* And a resultant TextChunk.charSpaceWidth comes to TextChunk constructor as 0.
* In this case every chunk is considered as a word boundary and space is added.
* We should consider charSpaceWidth equal (or close) to zero as a no-space.
*/
if (chunk.CharSpaceWidth < 0.1f)
{
return(false);
}
float dist = chunk.DistanceFromEndOf(previousChunk);
if (dist < -chunk.CharSpaceWidth || dist > chunk.CharSpaceWidth / 2.0f)
{
return(true);
}
return(false);
}
/**
* Returns the result so far.
* @return a String with the resulting text.
* @lineposition (input string parameter) :
* "first" - identifies first line in line-by-line mark processing;
* "last" - identifies last line in line-by-line mark processing;
* "" - middle lines in line-by-line mark processing.
*/
public virtual String GetResultantText(string lineposition)
{
if (DUMP_STATE)
{
DumpState();
}
locationalResult.Sort();
StringBuilder sb = new StringBuilder();
TextChunk lastChunk = null;
for (int i = 0; i < locationalResult.Count; i++)
{
TextChunk chunk = locationalResult[i];
if (lastChunk == null)
{
//if first chunk in first line contains alien symbols befere space - remove them
if (chunk.text.Contains(" ") && lineposition == "first")
{
int spacepos = chunk.text.IndexOf(" ");
chunk.text = chunk.text.Substring(spacepos + 1);
}
sb.Append(chunk.text);
}
else
{
if (chunk.SameLine(lastChunk))
{
float dist = chunk.DistanceFromEndOf(lastChunk);
if (dist < -chunk.charSpaceWidth)
{
sb.Append(' ');
}
// we only insert a blank space if the trailing character of the previous string wasn't a space, and the leading character of the current string isn't a space
else if (dist > chunk.charSpaceWidth / 2.0f && !StartsWithSpace(chunk.text) && !EndsWithSpace(lastChunk.text))
{
sb.Append(' ');
}
// if last chunk in last line contains alien symbols after space - remove them
if (i == locationalResult.Count - 1 && lineposition == "last")
{
if (chunk.text.Contains(" "))
{
int spaceposend = chunk.text.IndexOf(" ");
chunk.text = chunk.text.Remove(spaceposend);
}
}
sb.Append(chunk.text);
//add space in last chunk in not last line and if last chink not ends with space itself.
if (i == locationalResult.Count - 1 && lineposition != "last" && !EndsWithSpace(chunk.text))
{
sb.Append(' ');
}
}
else
{
sb.Append('\n');
sb.Append(chunk.text);
}
}
lastChunk = chunk;
}
return(sb.ToString());
}