Index: Trunk/Modules/Annulus/Annulus.UnitTests/SweptCollisionDetection/PolygonvsPolygonTests.cs
===================================================================
--- Trunk/Modules/Annulus/Annulus.UnitTests/SweptCollisionDetection/PolygonvsPolygonTests.cs	(revision 993)
+++ Trunk/Modules/Annulus/Annulus.UnitTests/SweptCollisionDetection/PolygonvsPolygonTests.cs	(working copy)
@@ -4350,7 +4350,286 @@
             }
         }
 
-        // Sliding
+        public class GlancingHits : UnitTestSharp.TestFixture
+        {
+            public void SquareSpinning()
+            {
+                var hSqrt2 = Math.Sqrt(2);
+                var polygonDiamont = new SimplePolygon(new Vector[]
+            {
+                new Vector(0, 1),
+                new Vector(1, 0),
+                new Vector(0,-1),
+                new Vector(-1,0),
+            });
+                var polygonSquare = new SimplePolygon(new Vector[]
+            {
+                new Vector(-1, 1),
+                new Vector( 1, 1),
+                new Vector( 1,-1),
+                new Vector(-1,-1),
+            });
+
+                var input = new PolygonvsPolygon.Input
+                {
+                    polygon_A = new PolygonvsPolygon.SimplePolygonInMotion
+                    {
+                        polygon = polygonSquare,
+                        motion = new Motion
+                        {
+                            AngularVelocity = Math.PI / 4,
+                            InitialPosition = new Vector(0, 1 + hSqrt2),
+                            LinearVelocity = new Vector(0, 0),
+                        },
+                        payload = 7,
+                    },
+
+                    polygon_B = new PolygonvsPolygon.SimplePolygonInMotion
+                    {
+                        polygon = polygonDiamont,
+                        motion = new Motion
+                        {
+
+                        },
+
+                        payload = 25,
+                    },
+
+                    impactWindow = new Interval(0, 8),
+                };
+
+                int iterations = 0;
+                var output = PolygonvsPolygon.FindIntersectionsInWindow(input, ref iterations);
+
+                var expected = new PolygonvsPolygon.Hit[]
+                {
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(3),
+                        VertexB = polygonDiamont.GetVertex(0),
+                        TOI = 1,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallel,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(0),
+                        VertexB = polygonDiamont.GetVertex(0),
+                        TOI = 3,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallel,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(1),
+                        VertexB = polygonDiamont.GetVertex(0),
+                        TOI = 5,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallel,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(2),
+                        VertexB = polygonDiamont.GetVertex(0),
+                        TOI = 7,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallel,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                };
+
+                CheckEqual(expected, output);
+            }
+
+            public void SquaresSliding()
+            {
+                var polygonSquare = new SimplePolygon(new Vector[]
+            {
+                new Vector(-1, 1),
+                new Vector( 1, 1),
+                new Vector( 1,-1),
+                new Vector(-1,-1),
+            });
+
+                var input = new PolygonvsPolygon.Input
+                {
+                    polygon_A = new PolygonvsPolygon.SimplePolygonInMotion
+                    {
+                        polygon = polygonSquare,
+                        motion = new Motion
+                        {
+                            InitialPosition = new Vector(3, 2),
+                            LinearVelocity = new Vector(-1, 0),
+                        },
+                        payload = 7,
+                    },
+
+                    polygon_B = new PolygonvsPolygon.SimplePolygonInMotion
+                    {
+                        polygon = polygonSquare,
+                        motion = new Motion
+                        {
+
+                        },
+
+                        payload = 25,
+                    },
+
+                    impactWindow = new Interval(0, 8),
+                };
+
+                int iterations = 0;
+                var output = PolygonvsPolygon.FindIntersectionsInWindow(input, ref iterations);
+
+                var expected = new PolygonvsPolygon.Hit[]
+                {
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(3),
+                        VertexB = polygonSquare.GetVertex(1),
+                        TOI = 1,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallelEntering,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.EdgeEdgeCollision
+                    {
+                        EdgeA = polygonSquare.GetEdge(2),
+                        EdgeB = polygonSquare.GetEdge(0),
+                        TrailingHitFraction = new Tuple<Scalar,Scalar>(0, 1),
+                        LeadingHitFraction = new Tuple<Scalar,Scalar>(1, 0), 
+                        TOI = 3,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallel,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(2),
+                        VertexB = polygonSquare.GetVertex(0),
+                        TOI = 5,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallelExiting,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                };
+
+
+                CheckEqual(expected, output);
+
+            }
+
+            public void SquaresSlideBack()
+            {
+                var polygonSquare = new SimplePolygon(new Vector[]
+            {
+                new Vector(-1, 1),
+                new Vector( 1, 1),
+                new Vector( 1,-1),
+                new Vector(-1,-1),
+            });
+
+                var input = new PolygonvsPolygon.Input
+                {
+                    polygon_A = new PolygonvsPolygon.SimplePolygonInMotion
+                    {
+                        polygon = polygonSquare,
+                        motion = new Motion
+                        {
+                            InitialPosition = new Vector(12, 2),
+                            LinearVelocity = new Vector(-3.5, 0),
+                            LinearAcceleration = new Vector(0.5, 0),
+                        },
+                        payload = 7,
+                    },
+
+                    polygon_B = new PolygonvsPolygon.SimplePolygonInMotion
+                    {
+                        polygon = polygonSquare,
+                        motion = new Motion
+                        {
+                            InitialPosition = new Vector(0, 0),
+                        },
+
+                        payload = 25,
+                    },
+
+                    impactWindow = new Interval(0, 20),
+                };
+
+                int iterations = 0;
+                var output = PolygonvsPolygon.FindIntersectionsInWindow(input, ref iterations);
+                var expected = new PolygonvsPolygon.Hit[]
+                {
+
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(3),
+                        VertexB = polygonSquare.GetVertex(1),
+                        TOI = 4,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallelEntering,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.EdgeEdgeCollision
+                    {
+                        EdgeA = polygonSquare.GetEdge(2),
+                        EdgeB = polygonSquare.GetEdge(0),
+                        TOI = 4.8,
+                        TrailingHitFraction = new Tuple<Scalar,Scalar>(0, 1),
+                        LeadingHitFraction = new Tuple<Scalar,Scalar>(1, 0),
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallel,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.EdgeEdgeCollision
+                    {
+                        EdgeA = polygonSquare.GetEdge(2),
+                        EdgeB = polygonSquare.GetEdge(0),
+                        TOI = 6,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallelExiting,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(2),
+                        VertexB = polygonSquare.GetVertex(0),
+                        TOI = 8,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallelEntering,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.EdgeEdgeCollision
+                    {
+                        EdgeA = polygonSquare.GetEdge(2),
+                        EdgeB = polygonSquare.GetEdge(0),
+                        TOI = 9.2,
+                        TrailingHitFraction = new Tuple<Scalar,Scalar>(1, 0),
+                        LeadingHitFraction = new Tuple<Scalar,Scalar>(0, 1),
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallel,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                    new PolygonvsPolygon.VertexVertexCollision
+                    {
+                        VertexA = polygonSquare.GetVertex(3),
+                        VertexB = polygonSquare.GetVertex(1),
+                        TOI = 10,
+                        Transition = PolygonvsPolygon.TransitionState.GlancingParallelExiting,
+                        PayloadA = input.polygon_A.payload,
+                        PayloadB = input.polygon_B.payload,
+                    },
+                };
+                CheckEqual(expected, output);
+
+            }
+
+        }
+        
         // edge edge
         // edge vertex
         // vertex vertex