Exemple #1
0
        public void TestExampleConvexHull()
        {
            var points = new List <Point>()
            {
                new Point(4, 21),
                new Point(3, 15),
                new Point(6, 9),
                new Point(7, 7),
                new Point(10, 5),
                new Point(11, 29),
                new Point(14, 29),
                new Point(27, 14),
                new Point(29, 18),
                new Point(27, 22)
            };
            var hull = PointMath.ComputeConvexHull(points);

            ExpectList(hull, new List <Point>()
            {
                new Point(3, 15),
                new Point(4, 21),
                new Point(11, 29),
                new Point(14, 29),
                new Point(27, 22),
                new Point(29, 18),
                new Point(27, 14),
                new Point(10, 5),
                new Point(7, 7)
            });
        }
Exemple #2
0
        public void TestConvexHull()
        {
            int seed = Environment.TickCount;
            var r    = new Random(55523173);

            var pts = new List <Point> {
                new Point(10, 22),
                new Point(10, 10),
                new Point(22, 20),
                new Point(20, 10)
            };

            for (int i = 0; i < 20; i++)
            {
                pts.Insert(r.Next(pts.Count + 1), new Point(r.Next(10, 21), r.Next(10, 21)));
            }

            var results = PointMath.ComputeConvexHull(pts, true);

            Assert.AreEqual(4, results.Count);
            Assert.That(results.Contains(new Point(10, 22)));
            Assert.That(results.Contains(new Point(10, 10)));
            Assert.That(results.Contains(new Point(22, 20)));
            Assert.That(results.Contains(new Point(20, 10)));

            for (int trial = 0; trial < 20; trial++)
            {
                // For our second test we use random points plus a possible outlier,
                // and check that all points are within or on the convex hull.
                int Lim = 100, PtCount = 5 * (trial + 1);
                pts.Clear();
                for (int i = 0; i < PtCount; i++)
                {
                    pts.Add(new Point(r.Next(-Lim, Lim), r.Next(-Lim, Lim)));
                }
                pts.Add(new Point(r.Next(Lim * -4, Lim * 4), r.Next(Lim * -4, Lim * 4)));

                results = PointMath.ComputeConvexHull(pts, true);

                for (int i = 0; i < pts.Count; i++)
                {
                    Assert.That(PolygonMath.IsPointInPolygon(results, pts[i]) || results.Contains(pts[i]),
                                "Fail for seed {0}, trial {1}, pts[{2}]", seed, trial, i);
                }
            }
        }
Exemple #3
0
        public void TestTrivialConvexHulls()
        {
            Point p = new Point(1, 2), q = new Point(2, 1);

            ExpectList(PointMath.ComputeConvexHull(new List <Point>()));
            ExpectList(PointMath.ComputeConvexHull(new List <Point>()
            {
                p
            }), p);
            ExpectList(PointMath.ComputeConvexHull(new List <Point>()
            {
                q
            }), q);
            ExpectList(PointMath.ComputeConvexHull(new List <Point>()
            {
                p, q
            }), p, q);
            ExpectList(PointMath.ComputeConvexHull(new List <Point>()
            {
                p, p, q
            }), p, q);
            ExpectList(PointMath.ComputeConvexHull(new List <Point>()
            {
                p, q, p
            }), p, q);

            // Ideally these would be the results, but it actually repeats p
            //ExpectList(PointMath.ComputeConvexHull(new List<Point>() { p, p }), p);
            //ExpectList(PointMath.ComputeConvexHull(new List<Point>() { p, p, p }), p);
            ExpectList(PointMath.ComputeConvexHull(new List <Point>()
            {
                p, p
            }), p, p);
            ExpectList(PointMath.ComputeConvexHull(new List <Point>()
            {
                p, p, p
            }), p, p);
        }