public void Build(SceneGraph scene)
        {
            BuildCache = new Dictionary<string, object>(StringComparer.CurrentCultureIgnoreCase);
            var camera = scene.First<SceneCamera>();
            Guard.NotNull(camera, "Couldn't find camera in scene");

            var cameras = scene.OfType<SceneCamera>().ToArray();
            Cameras = new Camera[cameras.Length];
            for (int i = 0; i < cameras.Length; i++)
            {
                Cameras[i] = new Camera();
                Cameras[i].LookAt(cameras[i].Position, cameras[i].Direction, cameras[i].Up);
                Cameras[i].Fov = camera.Fov;
                Cameras[i].BuildView();
            }

            var sceneGeometryData = scene.First<SceneMeshData>();
            Guard.NotNull(sceneGeometryData, "Couldn't find sceneGeometryData in scene");
            var sceneGeometry = scene.Subset<SceneMeshEntity>().ToArray();
            Guard.NotNullOrEmpty(sceneGeometry, "No scene geometry present");
            var sceneMaterials = scene.Subset<SceneMaterial>().ToArray();
            Guard.NotNullOrEmpty(sceneMaterials, "No scene materials present");
            var sceneLights = scene.Subset<SceneLightsource>().ToArray();
            Guard.NotNullOrEmpty(sceneLights, "No scene lightsources present");
            var sceneResources = scene.Subset<SceneResourceReference>().ToArray();
            Camera = new Camera();
            Camera.LookAt(camera.Position, camera.Direction, camera.Up);
            Camera.Fov = camera.Fov;
            Camera.BuildView();

            Tracer.WriteLine("Start Building Materials");
            this.BuildMaterials(sceneMaterials, sceneResources);

            BuildCache.Add("Materials", sceneMaterials);

            Tracer.WriteLine("Start Building Geometry");
            var areaLights = sceneLights.Where(lt => lt.LightType == LightSourceTypes.Area).ToArray();

            if (areaLights.Any())
            {
                BuildCache.Add("AreaLights", areaLights.ToArray());
            }

            this.BuildGeometry(sceneGeometryData, sceneGeometry, areaLights.Any(), areaLights);
            this.BoundingSphereRadius = sceneGeometryData.BoundingSphereRadius;
            BuildCache.Add("Geometry", sceneGeometry);

            Tracer.WriteLine("Start Building Lightsources");
            this.BuildLights(sceneLights);

            Session.Frame.TopObject = this.topObject;
        }