First commit.

Source/OpenNest.Core/Sequence.cs

@@ -0,0 +1,67 @@
+using System.Collections.Generic;
+
+namespace OpenNest
+{
+    public interface ISequencer
+    {
+        List<Part> SequenceParts(IList<Part> parts);
+        List<Part> SequenceParts(IList<Part> parts, Vector origin);
+    }
+
+    public class SequenceByNearest : ISequencer
+    {
+        public List<Part> SequenceParts(IList<Part> parts)
+        {
+            return SequenceParts(parts, Vector.Zero);
+        }
+
+        public List<Part> SequenceParts(IList<Part> parts, Vector origin)
+        {
+            if (parts.Count == 0)
+                return new List<Part>();
+
+            var dupList = new List<Part>(parts);
+            var seqList = new List<Part>(parts.Count);
+
+            var lastPart = GetClosestPart(origin, dupList);
+            seqList.Add(lastPart);
+            dupList.Remove(lastPart);
+
+            for (int i = 0; i < parts.Count - 1 /*STOP BEFORE LAST PART*/; i++)
+            {
+                var nextPart = GetClosestPart(lastPart.Location, dupList);
+
+                if (nextPart == null)
+                    break;
+
+                seqList.Add(nextPart);
+                dupList.Remove(nextPart);
+                lastPart = nextPart;
+            }
+
+            return seqList;
+        }
+
+        private Part GetClosestPart(Vector pt, IList<Part> parts)
+        {
+            if (parts.Count == 0)
+                return null;
+
+            var closestPart = parts[0];
+            var closestDistance = parts[0].Location.DistanceTo(pt);
+
+            for (int i = 1; i < parts.Count; i++)
+            {
+                var distance = parts[i].Location.DistanceTo(pt);
+
+                if (distance < closestDistance)
+                {
+                    closestPart = parts[i];
+                    closestDistance = distance;
+                }
+            }
+
+            return closestPart;
+        }
+    }
+}