/// <summary>Approximates a given Path with a List of Point objects</summary>
/// <param name="path">input path</param>
private static IList <Point> GetPathApproximation(Path path)
{
IList <Point> approx = new ApproxPoints();
foreach (Subpath subpath in path.GetSubpaths())
{
approx.AddAll(subpath.GetPiecewiseLinearApproximation());
}
return(approx);
}
private Path FilterStrokePath(Path sourcePath, Matrix ctm, float lineWidth, int lineCapStyle, int lineJoinStyle
, float miterLimit, LineDashPattern lineDashPattern)
{
Path path = sourcePath;
JoinType joinType = ClipperBridge.GetJoinType(lineJoinStyle);
EndType endType = ClipperBridge.GetEndType(lineCapStyle);
if (lineDashPattern != null)
{
if (!lineDashPattern.IsSolid())
{
path = LineDashPattern.ApplyDashPattern(path, lineDashPattern);
}
}
ClipperOffset offset = new ClipperOffset(miterLimit, PdfCleanUpTool.arcTolerance * PdfCleanUpTool.floatMultiplier
);
IList <Subpath> degenerateSubpaths = ClipperBridge.AddPath(offset, path, joinType, endType);
PolyTree resultTree = new PolyTree();
offset.Execute(ref resultTree, lineWidth * PdfCleanUpTool.floatMultiplier / 2);
Path offsetedPath = ClipperBridge.ConvertToPath(resultTree);
if (degenerateSubpaths.Count > 0)
{
if (endType == EndType.OPEN_ROUND)
{
IList <Subpath> circles = ConvertToCircles(degenerateSubpaths, lineWidth / 2);
offsetedPath.AddSubpaths(circles);
}
else
{
if (endType == EndType.OPEN_SQUARE && lineDashPattern != null)
{
IList <Subpath> squares = ConvertToSquares(degenerateSubpaths, lineWidth, sourcePath);
offsetedPath.AddSubpaths(squares);
}
}
}
return(FilterFillPath(offsetedPath, ctm, PdfCanvasConstants.FillingRule.NONZERO_WINDING));
}
/// <summary>Note: this method will close all unclosed subpaths of the passed path.</summary>
/// <param name="fillingRule">If the subpath is contour, pass any value.</param>
protected internal virtual Path FilterFillPath(Path path, Matrix ctm, int fillingRule)
{
path.CloseAllSubpaths();
Clipper clipper = new Clipper();
ClipperBridge.AddPath(clipper, path, PolyType.SUBJECT);
foreach (Rectangle rectangle in regions)
{
Point[] transfRectVertices = TransformPoints(ctm, true, GetRectangleVertices(rectangle));
ClipperBridge.AddRectToClipper(clipper, transfRectVertices, PolyType.CLIP);
}
PolyFillType fillType = PolyFillType.NON_ZERO;
if (fillingRule == PdfCanvasConstants.FillingRule.EVEN_ODD)
{
fillType = PolyFillType.EVEN_ODD;
}
PolyTree resultTree = new PolyTree();
clipper.Execute(ClipType.DIFFERENCE, resultTree, fillType, PolyFillType.NON_ZERO);
return(ClipperBridge.ConvertToPath(resultTree));
}
/// <summary>Converts specified degenerate subpaths to squares.</summary>
/// <remarks>
/// Converts specified degenerate subpaths to squares.
/// Note: the list of degenerate subpaths should contain at least 2 elements. Otherwise
/// we can't determine the direction which the rotation of each square depends on.
/// </remarks>
/// <param name="squareWidth">Width of each constructed square.</param>
/// <param name="sourcePath">The path which dash pattern applied to. Needed to calc rotation angle of each square.
/// </param>
/// <returns>
///
/// <see cref="System.Collections.IList{E}"/>
/// consisting of squares constructed on given degenerated subpaths.
/// </returns>
private static IList <Subpath> ConvertToSquares(IList <Subpath> degenerateSubpaths, double squareWidth, Path
sourcePath)
{
IList <Point> pathApprox = GetPathApproximation(sourcePath);
if (pathApprox.Count < 2)
{
return(JavaCollectionsUtil.EmptyList <Subpath>());
}
IEnumerator <Point> approxIter = pathApprox.GetEnumerator();
approxIter.MoveNext();
Point approxPt1 = approxIter.Current;
approxIter.MoveNext();
Point approxPt2 = approxIter.Current;
PdfCleanUpFilter.StandardLine line = new PdfCleanUpFilter.StandardLine(approxPt1, approxPt2);
IList <Subpath> squares = new List <Subpath>(degenerateSubpaths.Count);
float widthHalf = (float)squareWidth / 2;
foreach (Subpath subpath in degenerateSubpaths)
{
Point point = subpath.GetStartPoint();
while (!line.Contains(point))
{
approxPt1 = approxPt2;
approxIter.MoveNext();
approxPt2 = approxIter.Current;
line = new PdfCleanUpFilter.StandardLine(approxPt1, approxPt2);
}
double slope = line.GetSlope();
double angle;
if (!double.IsPositiveInfinity(slope))
{
angle = Math.Atan(slope);
}
else
{
angle = Math.PI / 2;
}
squares.Add(ConstructSquare(point, widthHalf, angle));
}
return(squares);
}
