public static bool AreDuplicateEntities(List <Point3d> source, List <Point3d> target)
{
if (source == null || source.Count == 0 || target == null || target.Count == 0)
{
return(false);
}
// 如果他们坐标完全一样，那么认为他们是相同的，无需再用clipperlib
if (AreIdenticalCoordinates(source, target.ToList()))
{
return(true);
}
// 有时候坐标太大，导致计算结果不正确，所以移到原点去计算
var vector = Point3d.Origin - source[0];
source = source.Select(it => it + vector).ToList();
target = target.Select(it => it + vector).ToList();
// Use clipper to calculate the intersection
var precision = 0.0001; // 精度不能太大，否则结果出错
var subject = new List <List <IntPoint> >(1);
var clipper = new List <List <IntPoint> >(1);
var result = new List <List <IntPoint> >();
// 用Math.Rount解决精度带来的影响。
var subjectPath = source.Select(it => new IntPoint(Math.Round(it.X / precision), Math.Round(it.Y / precision))).ToList();
subject.Add(subjectPath);
var clipperPath = target.Select(it => new IntPoint(Math.Round(it.X / precision), Math.Round(it.Y / precision))).ToList();
clipper.Add(clipperPath);
var cpr = new Clipper();
cpr.AddPaths(subject, PolyType.ptSubject, true);
cpr.AddPaths(clipper, PolyType.ptClip, true);
// 相同为0，相异为1
cpr.Execute(ClipType.ctXor, result, PolyFillType.pftNonZero, PolyFillType.pftNonZero);
if (result.Count == 0)
{
return(true);
}
foreach (var path in result)
{
var points = path.Select(it => new Point3d(it.X * precision, it.Y * precision, 0.0)).ToArray();
var polyline = CurveUtils.CreatePolygon(points);
// If the polygon's area is very small, just ignore, or it will bother user.
if (polyline.Area.Larger(0.001))
{
polyline.Dispose();
return(false);
}
polyline.Dispose();
}
return(true);
}