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Geometry/Line3d.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Geo
+{
+    [Serializable]
+    public class Line3d
+    {
+        Point3d startPoint;
+        Point3d endPoint;
+
+        public Point3d StartPoint { get => startPoint; set { startPoint = value; Directive = endPoint - startPoint; } }
+        public Point3d EndPoint { get => endPoint; set { endPoint = value; Directive = endPoint - startPoint; } }
+        public Vector3d Directive { get; private set; }
+        public double Length { get => Directive.Norma; }
+
+        public Line3d()
+        {
+
+        }
+
+        public Line3d(Point2d startPt, Point2d endPt)
+        {
+            startPoint = startPt.ToPoint3d(); endPoint = endPt.ToPoint3d();
+            Directive = endPoint - startPoint; ;
+        }
+
+        public Line3d(Point3d startPt, Point3d endPt)
+        {
+            startPoint = startPt; endPoint = endPt;
+            Directive = endPoint - startPoint; ;
+        }
+    }
+}