static public ClipperPolygons ToClipperPolygons(this IPolygon polygon)
{
Clipper c = new Clipper();
ClipperPolygons polygons = new ClipperPolygons(), result = new ClipperPolygons();
for (int r = 0, r_to = polygon.RingCount; r < r_to; r++)
{
var ring = polygon[r];
ring.Close();
var ringPoints = new List <IntPoint>();
for (int p = 0, p_to = ring.PointCount; p < p_to; p++)
{
ringPoints.Add(ring[p].ToClipperPointer());
}
polygons.Add(ringPoints);
}
c.AddPaths(polygons, PolyType.ptSubject, true);
if (c.Execute(ClipType.ctUnion, result) == true)
{
return(result);
}
return(null);
}
static public ClipperPolygons Buffer(this ClipperPolygons polygons, double distance)
{
ClipperPolygons result = new ClipperPolygons();
ClipperOffset co = new ClipperOffset();
co.AddPaths(polygons, JoinType.jtRound, EndType.etClosedPolygon);
co.Execute(ref result, distance * Acc);
return result;
}
private ClipperPolygons CombineLineSegments(ClipperPolygons lines)
{
PolylineReduction reduction = new PolylineReduction();
foreach (var points in lines)
{
reduction.AddLine(points);
}
return(reduction.Reduce());
}
static public IPolygon Merge(this List<IPolygon> polygons)
{
Clipper c = new Clipper();
foreach (var polygon in polygons)
{
c.AddPaths(polygon.ToClipperPolygons(), PolyType.ptSubject, true);
}
ClipperPolygons result = new ClipperPolygons();
if (c.Execute(ClipType.ctUnion, result, PolyFillType.pftPositive) == true)
{
return result.ToPolygon();
}
return null;
}
static public Polygon ToPolygon(this ClipperPolygons clipperPolygons)
{
Polygon result = new Polygon();
foreach (var clipperRing in clipperPolygons)
{
var ring = new Ring();
foreach (var clipperPoint in clipperRing)
{
ring.AddPoint(clipperPoint.ToPoint());
}
result.AddRing(ring);
}
return result;
}
static public IPolygon Clip(this IPolygon clippee, Envelope clipper)
{
var clippeePolygons = clippee.ToClipperPolygons();
var clipperPolygons = clipper.ToPolygon().ToClipperPolygons();
var c = new Clipper();
c.AddPaths(clippeePolygons, PolyType.ptSubject, true);
c.AddPaths(clipperPolygons, PolyType.ptClip, true);
ClipperPolygons result = new ClipperPolygons();
if (c.Execute(ClipType.ctIntersection, result) == true)
{
return result.ToPolygon();
}
return clippee;
}
private void AddPolygonCollider2DElements(ClipperPolygons polygons, List<XElement> xmlList)
{
if (polygons.Count == 0)
return;
// Add just one polygon collider that has all paths in it.
List<XElement> pathElements = new List<XElement>();
foreach (var path in polygons)
{
string data = String.Join(" ", path.Select(pt => String.Format("{0},{1}", pt.X * Program.Scale, pt.Y * Program.Scale)));
XElement pathElement = new XElement("Path", data);
pathElements.Add(pathElement);
}
XElement polyColliderElement = new XElement("PolygonCollider2D", pathElements);
xmlList.Add(polyColliderElement);
}
private void AddEdgeCollider2DElements(ClipperPolygons lines, List<XElement> xmlList)
{
if (lines.Count == 0)
return;
// Add one edge collider for every polyline
// Clipper does not combine line segments for us
var combined = CombineLineSegments(lines);
foreach (var points in combined)
{
string data = String.Join(" ", points.Select(pt => String.Format("{0},{1}", pt.X * Program.Scale, pt.Y * Program.Scale)));
XElement edgeCollider =
new XElement("EdgeCollider2D",
new XElement("Points", data));
xmlList.Add(edgeCollider);
}
}
private void AddEdgeCollider2DElements(ClipperPolygons lines, List <XElement> xmlList)
{
if (lines.Count == 0)
{
return;
}
// Add one edge collider for every polyline
// Clipper does not combine line segments for us
var combined = CombineLineSegments(lines);
foreach (var points in combined)
{
string data = String.Join(" ", points.Select(pt => String.Format("{0},{1}", pt.X * Program.Scale, pt.Y * Program.Scale)));
XElement edgeCollider =
new XElement("EdgeCollider2D",
new XElement("Points", data));
xmlList.Add(edgeCollider);
}
}
private void AddPolygonCollider2DElements(ClipperPolygons polygons, List <XElement> xmlList)
{
if (polygons.Count == 0)
{
return;
}
// Add just one polygon collider that has all paths in it.
List <XElement> pathElements = new List <XElement>();
foreach (var path in polygons)
{
string data = String.Join(" ", path.Select(pt => String.Format("{0},{1}", pt.X * Program.Scale, pt.Y * Program.Scale)));
XElement pathElement = new XElement("Path", data);
pathElements.Add(pathElement);
}
XElement polyColliderElement = new XElement("PolygonCollider2D", pathElements);
xmlList.Add(polyColliderElement);
}
public static List <List <Point> > DecomposeNonSimplePolygon(List <Point> points)
{
List <List <Point> > result = new List <List <Point> >();
ClipperPolygon polygon = new ClipperPolygon();
foreach (Point point in points)
{
IntPoint intPoint = new IntPoint(point.X, point.Y);
polygon.Add(intPoint);
}
ClipperPolygons polygons = Clipper.SimplifyPolygon(polygon, PolyFillType.pftEvenOdd);
foreach (List <IntPoint> item in polygons)
{
List <Point> pointList = new List <Point>();
foreach (IntPoint subitem in item)
{
pointList.Add(new Point((int)subitem.X, (int)subitem.Y));
}
result.Add(pointList);
}
return(result);
}
private ClipperPolygons CombineLineSegments(ClipperPolygons lines)
{
PolylineReduction reduction = new PolylineReduction();
foreach (var points in lines)
{
reduction.AddLine(points);
}
return reduction.Reduce();
}
