/// <summary>Calculates and returns the next element which is either gap or dash.</summary>
/// <returns>The next dash array's element.</returns>
private LineDashPattern.DashArrayElem Next()
{
LineDashPattern.DashArrayElem ret = currentElem;
if (dashArray.Size() > 0)
{
currentIndex = (currentIndex + 1) % dashArray.Size();
currentElem = new LineDashPattern.DashArrayElem(this, dashArray.GetAsNumber(currentIndex).FloatValue(), IsEven
(++elemOrdinalNumber));
}
return(ret);
}
/// <summary>Apply a LineDashPattern along a Path</summary>
/// <param name="path">input path</param>
/// <param name="lineDashPattern">input LineDashPattern</param>
/// <returns>a dashed Path</returns>
public static Path ApplyDashPattern(Path path, LineDashPattern lineDashPattern)
{
ICollection <int> modifiedSubpaths = new HashSet <int>(path.ReplaceCloseWithLine());
Path dashedPath = new Path();
int currentSubpath = 0;
foreach (Subpath subpath in path.GetSubpaths())
{
IList <Point> subpathApprox = subpath.GetPiecewiseLinearApproximation();
if (subpathApprox.Count > 1)
{
dashedPath.MoveTo((float)subpathApprox[0].GetX(), (float)subpathApprox[0].GetY());
float remainingDist = 0;
bool remainingIsGap = false;
for (int i = 1; i < subpathApprox.Count; ++i)
{
Point nextPoint = null;
if (remainingDist != 0)
{
nextPoint = GetNextPoint(subpathApprox[i - 1], subpathApprox[i], remainingDist);
remainingDist = ApplyDash(dashedPath, subpathApprox[i - 1], subpathApprox[i], nextPoint, remainingIsGap);
}
while (JavaUtil.FloatCompare(remainingDist, 0) == 0 && !dashedPath.GetCurrentPoint().Equals(subpathApprox[
i]))
{
LineDashPattern.DashArrayElem currentElem = lineDashPattern.Next();
nextPoint = GetNextPoint(nextPoint != null ? nextPoint : subpathApprox[i - 1], subpathApprox[i], currentElem
.GetVal());
remainingDist = ApplyDash(dashedPath, subpathApprox[i - 1], subpathApprox[i], nextPoint, currentElem.IsGap
());
remainingIsGap = currentElem.IsGap();
}
}
// If true, then the line closing the subpath was explicitly added (see Path.ReplaceCloseWithLine).
// This causes a loss of a visual effect of line join style parameter, so in this clause
// we simply add overlapping dash (or gap, no matter), which continues the last dash and equals to
// the first dash (or gap) of the path.
if (modifiedSubpaths.Contains(currentSubpath))
{
lineDashPattern.Reset();
LineDashPattern.DashArrayElem currentElem = lineDashPattern.Next();
Point nextPoint = GetNextPoint(subpathApprox[0], subpathApprox[1], currentElem.GetVal());
ApplyDash(dashedPath, subpathApprox[0], subpathApprox[1], nextPoint, currentElem.IsGap());
}
}
// According to PDF spec. line dash pattern should be restarted for each new subpath.
lineDashPattern.Reset();
++currentSubpath;
}
return(dashedPath);
}
private void InitFirst(float phase)
{
if (dashArray.Size() > 0)
{
while (phase > 0)
{
phase -= dashArray.GetAsNumber(currentIndex).FloatValue();
currentIndex = (currentIndex + 1) % dashArray.Size();
elemOrdinalNumber++;
}
if (phase < 0)
{
--elemOrdinalNumber;
--currentIndex;
currentElem = new LineDashPattern.DashArrayElem(this, -phase, IsEven(elemOrdinalNumber));
}
else
{
currentElem = new LineDashPattern.DashArrayElem(this, dashArray.GetAsNumber(currentIndex).FloatValue(), IsEven
(elemOrdinalNumber));
}
}
}
