private static IPolygon BinaryOperation(IPolygon p, IPolygon q, ClipType operationType)
{
if (p.IsEmpty && q.IsEmpty)
{
return(Polygon.Empty);
}
var boundingBox = Box2.Hull(p.BoundingBox(), q.BoundingBox());
var fixedP = ConvertToFixedPoint(p, boundingBox);
var fixedQ = ConvertToFixedPoint(q, boundingBox);
try
{
var clipper = new Clipper();
clipper.AddPaths(fixedP, PolyType.ptSubject, closed: true);
clipper.AddPaths(fixedQ, PolyType.ptClip, closed: true);
var fixedAnswer = new ClipperPolygon();
clipper.Execute(operationType, fixedAnswer);
return(ConvertToFloatingPoint(fixedAnswer, boundingBox));
}
catch (Exception e)
{
Console.WriteLine("EXCEPTION: {0}", e);
return(Polygon.Empty);
}
}
public void MinkowskiDifference_of_two_boxes_amounts_to_subtracting_minima_and_maxima()
{
var box1 = new Box2(new Interval(0.123, 0.456), new Interval(2.718, 3.141));
var box2 = new Box2(new Interval(0.0777, 0.0888), new Interval(-0.1, +0.1));
var expectedAnswer = Box2.Hull(box1.MinCorner - box2.MaxCorner, box1.MaxCorner - box2.MinCorner);
var actualAnswer = PolygonUtils.MinkowskiDifference(box1, box2);
ExpectPolygonsAreEqualWithinTolerance(actualAnswer, expectedAnswer, _tolerance);
}
private static IPolygon MultinaryOperation(IEnumerable <IPolygon> polygons, ClipType operationType)
{
var boundingBox = Box2.Hull(polygons.Select(p => p.BoundingBox()));
if (boundingBox.IsEmpty)
{
return(Polygon.Empty);
}
var first = polygons.First();
var rest = polygons.Skip(1);
if (!rest.Any())
{
return(first);
}
var fixedAnswer = ConvertToFixedPoint(first, boundingBox);
foreach (var p in rest)
{
var fixedP = ConvertToFixedPoint(p, boundingBox);
try
{
var clipper = new Clipper();
clipper.AddPaths(fixedAnswer, PolyType.ptSubject, closed: true);
clipper.AddPaths(fixedP, PolyType.ptClip, closed: true);
var tempAnswer = new ClipperPolygon();
clipper.Execute(operationType, tempAnswer);
fixedAnswer = tempAnswer;
}
catch (Exception e)
{
Console.WriteLine("EXCEPTION: {0}", e);
}
}
return(ConvertToFloatingPoint(fixedAnswer, boundingBox));
}
public static IPolygon MinkowskiDifference(IPolygon p, IPolygon q)
{
if (p.IsEmpty || q.IsEmpty)
{
return(Polygon.Empty);
}
var boundingBox = Box2.Hull(p.BoundingBox(), q.BoundingBox());
boundingBox = Box2.Hull(boundingBox, new Box2(-boundingBox.MaxCorner, boundingBox.Dimensions));
var fixedAnswer = new ClipperPolygon();
var fixedP = ConvertToFixedPoint(p, boundingBox);
foreach (var qContour in q.Contours)
{
var fixedQContour = MinusConvertToFixedPoint(qContour, boundingBox);
try
{
var clipper = new Clipper();
clipper.AddPaths(fixedAnswer, PolyType.ptSubject, closed: true);
clipper.AddPaths(Clipper.MinkowskiSum(fixedQContour, fixedP, pathIsClosed: true), PolyType.ptClip, closed: true);
var tempAnswer = new ClipperPolygon();
clipper.Execute(ClipType.ctUnion, tempAnswer);
fixedAnswer = tempAnswer;
}
catch (Exception e)
{
Console.WriteLine("EXCEPTION: {0}", e);
}
}
return(ConvertToFloatingPoint(fixedAnswer, boundingBox));
}
public Polygon(IEnumerable <IClosedPolyline> contours)
{
_contours = contours.ToReadOnlyList();
_boundingBox = Box2.Hull(_contours.SelectMany(c => c.Vertices));
}
public Polygon(IClosedPolyline contour)
{
_contours = contour.AsSingleton();
_boundingBox = Box2.Hull(contour.Vertices);
}