C# Plane.Intersect方法代码示例

		public void RayPick()
		{
			new Grid3D(new Size(10));
			var camera = Camera.Use<LookAtCamera>();
			camera.Position = 5 * Vector3D.One;
			var cube = new Model(new ModelData(new BoxMesh(Vector3D.One, Color.Red)), Vector3D.Zero);
			var floor = new Plane(Vector3D.UnitZ, 0.0f);
			//ncrunch: no coverage start
			new Command(point =>
			{
				var ray = camera.ScreenPointToRay(point);
				Vector3D? intersect = floor.Intersect(ray);
				if (intersect != null)
					cube.Position = (Vector3D)intersect;
			}).Add(new MouseButtonTrigger(MouseButton.Left, State.Pressed));
		}

		public void RayParallelToPlaneDoesntIntersect()
		{
			var ray = new Ray(Vector3D.One, Vector3D.UnitZ);
			var plane = new Plane(Vector3D.UnitY, Vector3D.Zero);
			Assert.IsNull(plane.Intersect(ray));
		}

		public void RayPointingAwayFromPlaneDoesntIntersect()
		{
			var ray = new Ray(3 * Vector3D.One, Vector3D.One);
			var plane = new Plane(Vector3D.UnitY, Vector3D.One);
			Assert.IsNull(plane.Intersect(ray));
		}

		private static void VerifyIntersectPoint(Ray ray, Plane plane, Vector3D expectedIntersect)
		{
			Assert.AreEqual(expectedIntersect, plane.Intersect(ray));
		}

		private static void VerifyScreenCenterIsTarget(Vector3D position, Vector3D target)
		{
			var camera = CreateLookAtCamera(position, target);
			var floor = new Plane(Vector3D.UnitY, target);
			Ray ray = camera.ScreenPointToRay(Vector2D.Half);
			Assert.IsTrue(target.IsNearlyEqual(floor.Intersect(ray).Value));
		}

		public void CreateTowerAtClickedPosition()
		{
			var floor = new Plane(Vector3D.UnitY, 0.0f);
			new Command(pos =>
			{ //ncrunch: no coverage start
				var ray = Camera.Current.ScreenPointToRay(ScreenSpace.Current.ToPixelSpace(pos));
				var position = floor.Intersect(ray).Value;
				new Tower(TowerType.Water, position); //ncrunch: no coverage end
			}).Add(new MouseButtonTrigger(MouseButton.Left, State.Releasing));
		}

		public static Vector3D? GetIntersectionWithFloor(Vector2D screenPosition)
		{
			var ray = Camera.Current.ScreenPointToRay(screenPosition);
			var floor = new Plane(Vector3D.UnitZ, 0.0f);
			return floor.Intersect(ray);
		}