DotNet 4.8.1 build of DotNetBar

2025-02-07 10:35:23 -05:00
parent 33439b63a0
commit 6b0a5d60f4
2609 changed files with 989814 additions and 7 deletions
--- a/Code/DevComponents.DotNetBar.Charts/ConvexHull.cs
+++ b/Code/DevComponents.DotNetBar.Charts/ConvexHull.cs
@@ -0,0 +1,137 @@
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.Text;
+
+namespace DevComponents.DotNetBar.Charts
+{
+    // Monotone Chain Convex Hull.
+    // It takes O(NlogN) in sorting & O(N) in actual convex hull calc for N points.
+
+    public static class ConvexHull
+    {
+        #region GetConvexHull
+
+        public static Point[] GetConvexHull(Point[] points)
+        {
+            int n = points.Length;
+
+            Array.Sort(points, 0, n, new PointComparer());
+
+            Point[] ans = new Point[2 * n];
+
+            int k = 0;
+            int start = 0;
+
+            // Bottom hull
+
+            Point lpt = Point.Empty;
+
+            for (int i = 0; i < n; i++)
+            {
+                Point p = points[i];
+
+                if (PtCompare(p, lpt) == 0)
+                    continue;
+
+                lpt = p;
+
+                while (k - start >= 2)
+                {
+                    Point sp1 = PtSub(p, ans[k - 1]);
+                    Point sp2 = PtSub(p, ans[k - 2]);
+
+                    if (PtCross(sp1, sp2) <= 0)
+                        break;
+
+                    k--;
+                }
+
+                ans[k++] = p;
+            }
+
+            k--;
+
+            // Top hull
+
+            start = k;
+            lpt = Point.Empty;
+
+            for (int i = n - 1; i >= 0; i--)
+            {
+                Point p = points[i];
+
+                if (PtCompare(p, lpt) == 0)
+                    continue;
+
+                lpt = p;
+
+                while (k - start >= 2)
+                {
+                    Point sp1 = PtSub(p, ans[k - 1]);
+                    Point sp2 = PtSub(p, ans[k - 2]);
+
+                    if (PtCross(sp1, sp2) <= 0)
+                        break;
+
+                    k--;
+                }
+
+                ans[k++] = p;
+            }
+
+            k--;
+
+            Point[] hullPoints = new Point[k + 1];
+            Array.Copy(ans, hullPoints, k);
+
+            hullPoints[k] = hullPoints[0];
+
+            return (hullPoints);
+        }
+
+        #endregion
+
+        #region PointComparer
+
+        private class PointComparer : IComparer<Point>
+        {
+            public int Compare(Point pt1, Point pt2)
+            {
+                return (ConvexHull.PtCompare(pt1, pt2));
+            }
+        }
+
+        #endregion
+
+        #region PtCompare
+
+        private static int PtCompare(Point pt1, Point pt2)
+        {
+            if (pt1.X == pt2.X)
+                return (pt1.Y - pt2.Y);
+
+            return (pt1.X - pt2.X);
+        }
+
+        #endregion
+
+        #region PtCross
+
+        private static int PtCross(Point pt1, Point pt2)
+        {
+            return (pt1.X * pt2.Y - pt1.Y * pt2.X);
+        }
+
+        #endregion
+
+        #region PtSub
+
+        private static Point PtSub(Point pt1, Point pt2)
+        {
+            return (new Point(pt1.X - pt2.X, pt1.Y - pt2.Y));
+        }
+
+        #endregion
+    }
+}