Add Voronoi tests.

src/Triangle.Tests/Helper.cs

@@ -10,16 +10,47 @@ static class Helper
         public static Contour Rectangle(double left, double top,
             double right, double bottom, int mark = 0)
         {
-            var points = new List<Vertex>(4);
-
-            points.Add(new Vertex(left, top, mark));
-            points.Add(new Vertex(right, top, mark));
-            points.Add(new Vertex(right, bottom, mark));
-            points.Add(new Vertex(left, bottom, mark));
+            var points = new List<Vertex>(4)
+            {
+                new Vertex(left, top, mark),
+                new Vertex(right, top, mark),
+                new Vertex(right, bottom, mark),
+                new Vertex(left, bottom, mark)
+            };
 
             return new Contour(points, mark, true);
         }
 
+        public static Polygon SplitRectangle(double left, double top,
+            double right, double bottom, int mark = 0)
+        {
+            double midX = (right - left) / 2;
+            double midY = (top - bottom) / 2;
+
+            var midTop = new Vertex(left + midX, top, mark);
+            var midBottom = new Vertex(left + midX, bottom, mark);
+
+            var points = new List<Vertex>(4)
+            {
+                new Vertex(left, top, mark),
+                midTop,
+                new Vertex(right, top, mark),
+                new Vertex(right, bottom, mark),
+                midBottom,
+                new Vertex(left, bottom, mark)
+            };
+
+            var poly = new Polygon();
+
+            poly.Add(new Contour(points, mark, true));
+            poly.Add(new Segment(midTop, midBottom));
+
+            poly.Regions.Add(new RegionPointer(left + midX / 2, bottom + midY / 2, 1));
+            poly.Regions.Add(new RegionPointer(right - midX / 2, bottom + midY / 2, 2));
+
+            return poly;
+        }
+
         public static Triangle CreateTriangle(int id, Vertex org, Vertex dest, Vertex apex)
         {
             var t = new Triangle() { id = id, hash = id };

src/Triangle.Tests/Voronoi/BoundedVoronoiTest.cs

@@ -0,0 +1,33 @@
+using NUnit.Framework;
+using System;
+using System.Linq;
+using TriangleNet.Meshing;
+using TriangleNet.Voronoi;
+
+namespace TriangleNet.Tests.Voronoi
+{
+    public class BoundedVoronoiTest
+    {
+        [Test]
+        public void TestBoundedVoronoi()
+        {
+            var p = Helper.SplitRectangle(-1, 1, 1, -1, 3);
+
+            var mesher = new GenericMesher();
+            var mesh = (Mesh)mesher.Triangulate(p);
+
+            var voronoi = new BoundedVoronoi(mesh);
+
+            // The "split rectangle" polygon has two region pointer set.
+            Assert.That(voronoi.Vertices.Count(v => v.Label == 1), Is.EqualTo(2));
+            Assert.That(voronoi.Vertices.Count(v => v.Label == 2), Is.EqualTo(2));
+
+            // The polygon has 6 boundary segments, so the Voronoi diagram
+            // should have 6 infinite edges (which are projected onto the
+            // boundary). Additionally, the 6 boundary vertices are part of
+            // the Voronoi diagram.
+            Assert.That(voronoi.Vertices.Count(v => v.Label == 0), Is.EqualTo(12));
+            Assert.That(voronoi.Vertices.Count(v => v.ID >= mesh.Triangles.Count), Is.EqualTo(12));
+        }
+    }
+}

src/Triangle.Tests/Voronoi/StandardVoronoiTest.cs

@@ -0,0 +1,31 @@
+using NUnit.Framework;
+using System;
+using System.Linq;
+using TriangleNet.Meshing;
+using TriangleNet.Voronoi;
+
+namespace TriangleNet.Tests.Voronoi
+{
+    public class StandardVoronoiTest
+    {
+        [Test]
+        public void TestStandardVoronoi()
+        {
+            var p = Helper.SplitRectangle(-1, 1, 1, -1, 3);
+
+            var mesher = new GenericMesher();
+            var mesh = (Mesh)mesher.Triangulate(p);
+
+            var voronoi = new StandardVoronoi(mesh);
+
+            // The "split rectangle" polygon has two region pointer set.
+            Assert.That(voronoi.Vertices.Count(v => v.Label == 1), Is.EqualTo(2));
+            Assert.That(voronoi.Vertices.Count(v => v.Label == 2), Is.EqualTo(2));
+
+            // The polygon has 6 boundary segments, so the Voronoi diagram
+            // should have 6 infinite edges.
+            Assert.That(voronoi.Vertices.Count(v => v.Label == 0), Is.EqualTo(6));
+            Assert.That(voronoi.Vertices.Count(v => v.ID >= mesh.Triangles.Count), Is.EqualTo(6));
+        }
+    }
+}