private void JustifyLine(TextNode node, float targetLength)
{
bool justifiable = false;
if (node == null)
return;
var headNode = node; //keep track of the head node
//start by finding the length of the block of text that we know will actually fit:
int charGaps = 0;
int spaceGaps = 0;
bool atLeastOneNodeCosumedOnLine = false;
float length = 0;
var expandEndNode = node; //the node at the end of the smaller list (before adding additional word)
for (; node != null; node = node.Next)
{
if (node.Type == TextNodeType.LineBreak)
break;
if (SkipTrailingSpace(node, length, targetLength) && atLeastOneNodeCosumedOnLine)
{
justifiable = true;
break;
}
if (length + node.Length < targetLength || !atLeastOneNodeCosumedOnLine)
{
expandEndNode = node;
if (node.Type == TextNodeType.Space)
spaceGaps++;
if (node.Type == TextNodeType.Word)
{
charGaps += (node.Text.Length - 1);
//word was part of a crumbled word, so there's an extra char cap between the two words
if (CrumbledWord(node))
charGaps++;
}
atLeastOneNodeCosumedOnLine = true;
length += node.Length;
}
else
{
justifiable = true;
break;
}
}
//now we check how much additional length is added by adding an additional word to the line
float extraLength = 0f;
int extraSpaceGaps = 0;
int extraCharGaps = 0;
bool contractPossible = false;
TextNode contractEndNode = null;
for (node = expandEndNode.Next; node != null; node = node.Next)
{
if (node.Type == TextNodeType.LineBreak)
break;
if (node.Type == TextNodeType.Space)
{
extraLength += node.Length;
extraSpaceGaps++;
}
else if (node.Type == TextNodeType.Word)
{
contractEndNode = node;
contractPossible = true;
extraLength += node.Length;
extraCharGaps += (node.Text.Length - 1);
break;
}
}
if (justifiable)
{
//last part of this condition is to ensure that the full contraction is possible (it is all or nothing with contractions, since it looks really bad if we don't manage the full)
bool contract = contractPossible && (extraLength + length - targetLength) * Options.JustifyContractionPenalty < (targetLength - length) &&
((targetLength - (length + extraLength + 1)) / targetLength > -Options.JustifyCapContract);
if((!contract && length < targetLength) || (contract && length + extraLength > targetLength)) //calculate padding pixels per word and char
{
if (contract)
{
length += extraLength + 1;
charGaps += extraCharGaps;
spaceGaps += extraSpaceGaps;
}
int totalPixels = (int)(targetLength - length); //the total number of pixels that need to be added to line to justify it
int spacePixels = 0; //number of pixels to spread out amongst spaces
int charPixels = 0; //number of pixels to spread out amongst char gaps
if (contract)
{
if (totalPixels / targetLength < -Options.JustifyCapContract)
totalPixels = (int)(-Options.JustifyCapContract * targetLength);
}
else
{
if (totalPixels / targetLength > Options.JustifyCapExpand)
totalPixels = (int)(Options.JustifyCapExpand * targetLength);
}
//work out how to spread pixles between character gaps and word spaces
if (charGaps == 0)
{
spacePixels = totalPixels;
}
else if (spaceGaps == 0)
{
charPixels = totalPixels;
}
else
{
if(contract)
charPixels = (int)(totalPixels * Options.JustifyCharacterWeightForContract * charGaps / spaceGaps);
else
charPixels = (int)(totalPixels * Options.JustifyCharacterWeightForExpand * charGaps / spaceGaps);
if ((!contract && charPixels > totalPixels) ||
(contract && charPixels < totalPixels) )
charPixels = totalPixels;
spacePixels = totalPixels - charPixels;
}
int pixelsPerChar = 0; //minimum number of pixels to add per char
int leftOverCharPixels = 0; //number of pixels remaining to only add for some chars
if (charGaps != 0)
{
pixelsPerChar = charPixels / charGaps;
leftOverCharPixels = charPixels - pixelsPerChar * charGaps;
}
int pixelsPerSpace = 0; //minimum number of pixels to add per space
int leftOverSpacePixels = 0; //number of pixels remaining to only add for some spaces
if (spaceGaps != 0)
{
pixelsPerSpace = spacePixels / spaceGaps;
leftOverSpacePixels = spacePixels - pixelsPerSpace * spaceGaps;
}
//now actually iterate over all nodes and set tweaked length
for (node = headNode; node != null; node = node.Next)
{
if (node.Type == TextNodeType.Space)
{
node.LengthTweak = pixelsPerSpace;
if (leftOverSpacePixels > 0)
{
node.LengthTweak += 1;
leftOverSpacePixels--;
}
else if (leftOverSpacePixels < 0)
{
node.LengthTweak -= 1;
leftOverSpacePixels++;
}
}
else if (node.Type == TextNodeType.Word)
{
int cGaps = (node.Text.Length - 1);
if (CrumbledWord(node))
cGaps++;
node.LengthTweak = cGaps * pixelsPerChar;
if (leftOverCharPixels >= cGaps)
{
node.LengthTweak += cGaps;
leftOverCharPixels -= cGaps;
}
else if (leftOverCharPixels <= -cGaps)
{
node.LengthTweak -= cGaps;
leftOverCharPixels += cGaps;
}
else
{
node.LengthTweak += leftOverCharPixels;
leftOverCharPixels = 0;
}
}
if ((!contract && node == expandEndNode) || (contract && node == contractEndNode))
break;
}
}
}
}
