Adjust project structure

src/Shared/HandyControl_Shared/Expression/Drawing/PolylineHelper.cs

@@ -0,0 +1,116 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace HandyControl.Expression.Drawing
+{
+    internal static class PolylineHelper
+    {
+        public static IEnumerable<PolylineData> GetWrappedPolylines(IList<PolylineData> lines,
+            ref double startArcLength)
+        {
+            var count = 0;
+            for (var i = 0; i < lines.Count; i++)
+            {
+                count = i;
+                startArcLength -= lines[i].TotalLength;
+                if (MathHelper.LessThanOrClose(startArcLength, 0.0)) break;
+            }
+
+            if (!MathHelper.LessThanOrClose(startArcLength, 0.0))
+                throw new ArgumentOutOfRangeException(nameof(startArcLength));
+            startArcLength += lines[count].TotalLength;
+            return lines.Skip(count).Concat(lines.Take(count + 1));
+        }
+
+        public static void PathMarch(PolylineData polyline, double startArcLength, double cornerThreshold,
+            Func<MarchLocation, double> stopCallback)
+        {
+            if (polyline == null) throw new ArgumentNullException(nameof(polyline));
+            var count = polyline.Count;
+            if (count <= 1) throw new ArgumentOutOfRangeException(nameof(polyline));
+            var flag = false;
+            var x = startArcLength;
+            var before = 0.0;
+            var index = 0;
+            var num5 = Math.Cos(cornerThreshold * 3.1415926535897931 / 180.0);
+            while (true)
+            {
+                var num6 = polyline.Lengths[index];
+                if (!MathHelper.IsFiniteDouble(x)) return;
+                if (MathHelper.IsVerySmall(x))
+                {
+                    x = stopCallback(MarchLocation.Create(MarchStopReason.CompleteStep, index, before,
+                        num6 - before, x));
+                    flag = true;
+                }
+                else if (MathHelper.GreaterThan(x, 0.0))
+                {
+                    if (MathHelper.LessThanOrClose(x + before, num6))
+                    {
+                        before += x;
+                        x = stopCallback(MarchLocation.Create(MarchStopReason.CompleteStep, index, before,
+                            num6 - before, 0.0));
+                        flag = true;
+                    }
+                    else if (index < count - 2)
+                    {
+                        index++;
+                        var num7 = num6 - before;
+                        x -= num7;
+                        before = 0.0;
+                        // ReSharper disable once CompareOfFloatsByEqualityOperator
+                        if (flag && num5 != 1.0 && polyline.Angles[index] > num5)
+                        {
+                            num6 = polyline.Lengths[index];
+                            x = stopCallback(MarchLocation.Create(MarchStopReason.CornerPoint, index, before,
+                                num6 - before, x));
+                        }
+                    }
+                    else
+                    {
+                        var num8 = num6 - before;
+                        x -= num8;
+                        num6 = polyline.Lengths[index];
+                        before = polyline.Lengths[index];
+                        x = stopCallback(MarchLocation.Create(MarchStopReason.CompletePolyline, index, before,
+                            num6 - before, x));
+                        flag = true;
+                    }
+                }
+                else if (MathHelper.LessThan(x, 0.0))
+                {
+                    if (MathHelper.GreaterThanOrClose(x + before, 0.0))
+                    {
+                        before += x;
+                        x = stopCallback(MarchLocation.Create(MarchStopReason.CompleteStep, index, before,
+                            num6 - before, 0.0));
+                        flag = true;
+                    }
+                    else if (index > 0)
+                    {
+                        index--;
+                        x += before;
+                        before = polyline.Lengths[index];
+                        // ReSharper disable once CompareOfFloatsByEqualityOperator
+                        if (flag && num5 != 1.0 && polyline.Angles[index + 1] > num5)
+                        {
+                            num6 = polyline.Lengths[index];
+                            x = stopCallback(MarchLocation.Create(MarchStopReason.CornerPoint, index, before,
+                                num6 - before, x));
+                        }
+                    }
+                    else
+                    {
+                        x += before;
+                        num6 = polyline.Lengths[index];
+                        before = 0.0;
+                        x = stopCallback(MarchLocation.Create(MarchStopReason.CompletePolyline, index, before,
+                            num6 - before, x));
+                        flag = true;
+                    }
+                }
+            }
+        }
+    }
+}