public override void Run()
        {
            #region Create renderers

            // Note: the renderers take care of creating their own
            // device resources and listen for DeviceManager.OnInitialize

            // Create a axis-grid renderer
            var axisGrid = ToDispose(new AxisGridRenderer());
            axisGrid.Initialize(this);

            // Create and initialize the mesh renderer
            var loadedMesh = Common.Mesh.LoadFromFile("Tree.cmo");
            loadedMesh.AddRange(Common.Mesh.LoadFromFile("Plane.cmo"));
            loadedMesh.AddRange(Common.Mesh.LoadFromFile("Cube.cmo"));
            //loadedMesh.AddRange(Common.Mesh.LoadFromFile("SkullLo.cmo"));
            loadedMesh.AddRange(Common.Mesh.LoadFromFile("SkullHi.cmo"));

            List <DisplacedMeshRenderer> meshes = new List <DisplacedMeshRenderer>();
            meshes.AddRange((from mesh in loadedMesh
                             select ToDispose(new DisplacedMeshRenderer(mesh))));
            foreach (var m in meshes)
            {
                m.Initialize(this);
                m.World = Matrix.Identity;
            }

            // Set the first animation as the current animation and start clock
            foreach (var m in meshes)
            {
                if (m.Mesh.Animations != null && m.Mesh.Animations.Any())
                {
                    m.CurrentAnimation = m.Mesh.Animations.First().Value;
                }
                m.Clock.Start();
            }

            var triangle = new TriangleRenderer();
            triangle.Initialize(this);

            // Create and initialize a Direct2D FPS text renderer
            var fps = ToDispose(new Common.FpsRenderer("Calibri", Color.CornflowerBlue, new Point(8, 8), 16));
            fps.Initialize(this);

            // Create and initialize a general purpose Direct2D text renderer
            // This will display some instructions and the current view and rotation offsets
            var textRenderer = ToDispose(new Common.TextRenderer("Calibri", Color.CornflowerBlue, new Point(8, 40), 12));
            textRenderer.Initialize(this);

            #endregion

            // Initialize the world matrix
            var worldMatrix = Matrix.Identity;

            // Set the camera position
            var cameraPosition = new Vector3(0, 0, 2);
            var cameraTarget   = Vector3.Zero;  // Looking at the origin 0,0,0
            var cameraUp       = Vector3.UnitY; // Y+ is Up

            // Prepare matrices
            // Create the view matrix from our camera position, look target and up direction
            var viewMatrix = Matrix.LookAtRH(cameraPosition, cameraTarget, cameraUp);
            viewMatrix.TranslationVector += new Vector3(0, -0.98f, 0);

            // Create the projection matrix
            /* FoV 60degrees = Pi/3 radians */
            // Aspect ratio (based on window size), Near clip, Far clip
            var projectionMatrix = Matrix.PerspectiveFovRH((float)Math.PI / 3f, Width / (float)Height, 0.1f, 100f);

            // Maintain the correct aspect ratio on resize
            Window.Resize += (s, e) =>
            {
                projectionMatrix = Matrix.PerspectiveFovRH((float)Math.PI / 3f, Width / (float)Height, 0.1f, 100f);
            };

            #region Rotation and window event handlers

            // Create a rotation vector to keep track of the rotation
            // around each of the axes
            var rotation              = new Vector3(0.0f, 0.0f, 0.0f);
            var tessellationFactor    = 1f;
            var tessellationPartition = "Integer";
            var tessellationMethod    = "Phong";
            var displacementScale     = 0.02f;
            // We will call this action to update text
            // for the text renderer
            Action updateText = () =>
            {
                textRenderer.Text =
                    String.Format("Tessellation Factor: {0:#0.0} (+/- to change)"
                                  + "\nPartitioning: {1} (F1,F2,F3,F4 to change)"
                                  + "\nTessellation: {2} (F5,F6,F7)"
                                  + "\nDisplacement: {3:#0.000} (Shift +/- to change)"
                                  + "\nPress F to toggle wireframe | Shift+N toggle Normal Map | N show normals"
                                  + "\nPress 1-8 to switch pixel shaders | Backspace to cycle meshes",
                                  tessellationFactor,
                                  tessellationPartition,
                                  tessellationMethod,
                                  displacementScale,
                                  DeviceManager.Direct3DDevice.NativePointer);
            };

            Dictionary <Keys, bool> keyToggles = new Dictionary <Keys, bool>();
            keyToggles[Keys.Z] = false;
            keyToggles[Keys.F] = false;

            // Support keyboard/mouse input to rotate or move camera view
            var moveFactor             = 0.02f; // how much to change on each keypress
            var shiftKey               = false;
            var ctrlKey                = false;
            var background             = Color.White;
            var activeTriTessellator   = tessellateTriIntegerShader;
            var activePnTriTessellator = pnTriIntegerShader;
            var usePhongTessellation   = true;
            var usePNTessellation      = false;
            var showNormals            = false;
            var enableNormalMap        = true;
            var meshIndex              = 0;
            Window.KeyDown += (s, e) =>
            {
                var context = DeviceManager.Direct3DContext;

                shiftKey = e.Shift;
                ctrlKey  = e.Control;

                switch (e.KeyCode)
                {
                // WASD -> pans view
                case Keys.A:
                    viewMatrix.TranslationVector += new Vector3(moveFactor * 2, 0f, 0f);
                    break;

                case Keys.D:
                    viewMatrix.TranslationVector -= new Vector3(moveFactor * 2, 0f, 0f);
                    break;

                case Keys.S:
                    if (shiftKey)
                    {
                        viewMatrix.TranslationVector += new Vector3(0f, moveFactor * 2, 0f);
                    }
                    else
                    {
                        viewMatrix.TranslationVector -= new Vector3(0f, 0f, 1) * moveFactor * 2;
                    }
                    break;

                case Keys.W:
                    if (shiftKey)
                    {
                        viewMatrix.TranslationVector -= new Vector3(0f, moveFactor * 2, 0f);
                    }
                    else
                    {
                        viewMatrix.TranslationVector += new Vector3(0f, 0f, 1) * moveFactor * 2;
                    }
                    break;

                // Up/Down and Left/Right - rotates around X / Y respectively
                // (Mouse wheel rotates around Z)
                case Keys.Down:
                    worldMatrix *= Matrix.RotationX(moveFactor);
                    rotation    += new Vector3(moveFactor, 0f, 0f);
                    break;

                case Keys.Up:
                    worldMatrix *= Matrix.RotationX(-moveFactor);
                    rotation    -= new Vector3(moveFactor, 0f, 0f);
                    break;

                case Keys.Left:
                    worldMatrix *= Matrix.RotationY(moveFactor);
                    rotation    += new Vector3(0f, moveFactor, 0f);
                    break;

                case Keys.Right:
                    worldMatrix *= Matrix.RotationY(-moveFactor);
                    rotation    -= new Vector3(0f, moveFactor, 0f);
                    break;

                case Keys.T:
                    fps.Show          = !fps.Show;
                    textRenderer.Show = !textRenderer.Show;
                    break;

                case Keys.B:
                    if (background == Color.White)
                    {
                        background = new Color(30, 30, 34);
                    }
                    else
                    {
                        background = Color.White;
                    }
                    break;

                case Keys.G:
                    axisGrid.Show = !axisGrid.Show;
                    break;

                case Keys.P:
                    // Pause or resume mesh animation
                    meshes.ForEach(m => {
                        if (m.Clock.IsRunning)
                        {
                            m.Clock.Stop();
                        }
                        else
                        {
                            m.Clock.Start();
                        }
                    });
                    break;

                case Keys.X:
                    // To test for correct resource recreation
                    // Simulate device reset or lost.
                    System.Diagnostics.Debug.WriteLine(SharpDX.Diagnostics.ObjectTracker.ReportActiveObjects());
                    DeviceManager.Initialize(DeviceManager.Dpi);
                    System.Diagnostics.Debug.WriteLine(SharpDX.Diagnostics.ObjectTracker.ReportActiveObjects());
                    break;

                case Keys.Z:
                    keyToggles[Keys.Z] = !keyToggles[Keys.Z];
                    if (keyToggles[Keys.Z])
                    {
                        context.PixelShader.Set(depthPixelShader);
                    }
                    else
                    {
                        context.PixelShader.Set(pixelShader);
                    }
                    break;

                case Keys.F:
                    keyToggles[Keys.F] = !keyToggles[Keys.F];
                    RasterizerStateDescription rasterDesc;
                    if (context.Rasterizer.State != null)
                    {
                        rasterDesc = context.Rasterizer.State.Description;
                    }
                    else
                    {
                        rasterDesc = new RasterizerStateDescription()
                        {
                            CullMode = CullMode.None,
                            FillMode = FillMode.Solid
                        }
                    };
                    if (keyToggles[Keys.F])
                    {
                        rasterDesc.FillMode      = FillMode.Wireframe;
                        context.Rasterizer.State = ToDispose(new RasterizerState(context.Device, rasterDesc));
                    }
                    else
                    {
                        rasterDesc.FillMode      = FillMode.Solid;
                        context.Rasterizer.State = ToDispose(new RasterizerState(context.Device, rasterDesc));
                    }
                    break;

                case Keys.N:
                    if (!shiftKey)
                    {
                        showNormals = !showNormals;
                    }
                    else
                    {
                        enableNormalMap = !enableNormalMap;
                    }

                    break;

                case Keys.D1:
                    context.PixelShader.Set(pixelShader);
                    break;

                case Keys.D2:
                    context.PixelShader.Set(lambertShader);
                    break;

                case Keys.D3:
                    context.PixelShader.Set(phongShader);
                    break;

                case Keys.D4:
                    context.PixelShader.Set(blinnPhongShader);
                    break;

                case Keys.Add:
                    var multiple = 1.0f;
                    if (ctrlKey)
                    {
                        multiple = 3.0f;
                    }
                    if (!shiftKey)
                    {
                        tessellationFactor += 0.2f * multiple;
                        tessellationFactor  = Math.Min(tessellationFactor, 64);
                    }
                    else
                    {
                        displacementScale += 0.005f * multiple;
                    }
                    break;

                case Keys.Subtract:
                    multiple = 1.0f;
                    if (ctrlKey)
                    {
                        multiple = 3.0f;
                    }
                    if (!shiftKey)
                    {
                        tessellationFactor -= 0.2f * multiple;
                        tessellationFactor  = Math.Max(tessellationFactor, 0);
                    }
                    else
                    {
                        displacementScale -= 0.005f * multiple;
                    }
                    break;

                case Keys.F1:
                    tessellationPartition  = "Integer";
                    activeTriTessellator   = tessellateTriIntegerShader;
                    activePnTriTessellator = pnTriIntegerShader;
                    break;

                case Keys.F2:
                    tessellationPartition  = "Pow2";
                    activeTriTessellator   = tessellateTriPow2Shader;
                    activePnTriTessellator = pnTriPow2Shader;
                    break;

                case Keys.F3:
                    tessellationPartition  = "Fractional Even";
                    activeTriTessellator   = tessellateTriFractionalEvenShader;
                    activePnTriTessellator = pnTriFractionalEvenShader;
                    break;

                case Keys.F4:
                    tessellationPartition  = "Fractional Odd";
                    activeTriTessellator   = tessellateTriFractionalOddShader;
                    activePnTriTessellator = pnTriFractionalOddShader;
                    break;

                case Keys.F5:
                    usePhongTessellation = false;
                    usePNTessellation    = false;
                    tessellationMethod   = "Tri + displacement";
                    break;

                case Keys.F6:
                    usePhongTessellation = true;
                    usePNTessellation    = false;
                    tessellationMethod   = "Phong + displacement";
                    break;

                case Keys.F7:
                    usePhongTessellation = false;
                    usePNTessellation    = true;
                    tessellationMethod   = "PN-Triangle + displacement";
                    break;

                case Keys.Back:
                    meshIndex = (meshIndex + 1) % meshes.Count;
                    break;
                }

                updateText();
            };
            Window.KeyUp += (s, e) =>
            {
                // Clear the shift/ctrl keys so they aren't sticky
                if (e.KeyCode == Keys.ShiftKey)
                {
                    shiftKey = false;
                }
                if (e.KeyCode == Keys.ControlKey)
                {
                    ctrlKey = false;
                }
            };
            Window.MouseWheel += (s, e) =>
            {
                if (shiftKey)
                {
                    // Zoom in/out
                    viewMatrix.TranslationVector += new Vector3(0f, 0f, (e.Delta / 120f) * moveFactor * 2);
                }
                else
                {
                    // rotate around Z-axis
                    viewMatrix *= Matrix.RotationZ((e.Delta / 120f) * moveFactor);
                    rotation   += new Vector3(0f, 0f, (e.Delta / 120f) * moveFactor);
                }
                updateText();
            };

            var lastX = 0;
            var lastY = 0;

            Window.MouseDown += (s, e) =>
            {
                if (e.Button == MouseButtons.Left)
                {
                    lastX = e.X;
                    lastY = e.Y;
                }
            };

            Window.MouseMove += (s, e) =>
            {
                if (e.Button == MouseButtons.Left)
                {
                    var yRotate = lastX - e.X;
                    var xRotate = lastY - e.Y;
                    lastY = e.Y;
                    lastX = e.X;

                    // Mouse move changes
                    viewMatrix *= Matrix.RotationX(-xRotate * moveFactor);
                    viewMatrix *= Matrix.RotationY(-yRotate * moveFactor);

                    updateText();
                }
            };

            // Display instructions with initial values
            updateText();

            #endregion

            var clock = new System.Diagnostics.Stopwatch();
            clock.Start();

            #region Render loop

            // Create and run the render loop
            RenderLoop.Run(Window, () =>
            {
                // Start of frame:

                // Retrieve immediate context
                var context = DeviceManager.Direct3DContext;

                // Clear depth stencil view
                context.ClearDepthStencilView(DepthStencilView, DepthStencilClearFlags.Depth | DepthStencilClearFlags.Stencil, 1.0f, 0);
                // Clear render target view
                context.ClearRenderTargetView(RenderTargetView, background);

                // Create viewProjection matrix
                var viewProjection = Matrix.Multiply(viewMatrix, projectionMatrix);

                // Extract camera position from view
                var camPosition = Matrix.Transpose(Matrix.Invert(viewMatrix)).Column4;
                cameraPosition  = new Vector3(camPosition.X, camPosition.Y, camPosition.Z);

                // If Keys.CtrlKey is down, auto rotate viewProjection based on time
                var time = clock.ElapsedMilliseconds / 1000.0f;

                var perFrame                = new ConstantBuffers.PerFrame();
                perFrame.Light.Color        = new Color(0.8f, 0.8f, 0.8f, 1.0f);
                var lightDir                = Vector3.Transform(new Vector3(1f, -1f, -1f), worldMatrix);
                perFrame.Light.Direction    = new Vector3(lightDir.X, lightDir.Y, lightDir.Z);// new Vector3(Vector3.Transform(new Vector3(1f, -1f, 1f), worldMatrix * worldRotation).ToArray().Take(3).ToArray());
                perFrame.CameraPosition     = cameraPosition;
                perFrame.TessellationFactor = tessellationFactor;
                context.UpdateSubresource(ref perFrame, perFrameBuffer);

                // Render each object

                var perMaterial           = new ConstantBuffers.PerMaterial();
                perMaterial.Ambient       = new Color4(0.2f);
                perMaterial.Diffuse       = Color.White;
                perMaterial.Emissive      = new Color4(0);
                perMaterial.Specular      = Color.White;
                perMaterial.SpecularPower = 20f;
                perMaterial.HasTexture    = 0;
                perMaterial.UVTransform   = Matrix.Identity;
                context.UpdateSubresource(ref perMaterial, perMaterialBuffer);

                var perObject = new ConstantBuffers.PerObject();

                // MESH
                context.VertexShader.Set(tessellateVertexShader);
                context.HullShader.Set(activeTriTessellator);
                if (usePhongTessellation)
                {
                    context.DomainShader.Set(tessellatePhongDomainShader);
                }
                else if (usePNTessellation)
                {
                    context.HullShader.Set(activePnTriTessellator);
                    context.DomainShader.Set(pnTriDomainShader);
                }
                else
                {
                    context.DomainShader.Set(tessellateTriDomainShader);
                }

                var m = meshes[meshIndex];
                //meshes.ForEach((m) =>
                //{
                // Provide the material constant buffer to the mesh renderer
                perObject.World = m.World * worldMatrix;
                perObject.WorldInverseTranspose = Matrix.Transpose(Matrix.Invert(perObject.World));
                perObject.WorldViewProjection   = perObject.World * viewProjection;
                perObject.ViewProjection        = viewProjection;
                perObject.Transpose();
                context.UpdateSubresource(ref perObject, perObjectBuffer);

                m.EnableNormalMap   = enableNormalMap;
                m.DisplacementScale = displacementScale;
                m.DisplaceMidLevel  = 0.5f;
                m.PerMaterialBuffer = perMaterialBuffer;
                m.PerArmatureBuffer = perArmatureBuffer;
                m.Render();

                if (showNormals)
                {
                    using (var prevPixelShader = context.PixelShader.Get())
                    {
                        perMaterial.HasTexture  = 0;
                        perMaterial.UVTransform = Matrix.Identity;
                        context.UpdateSubresource(ref perMaterial, perMaterialBuffer);
                        context.PixelShader.Set(pixelShader);

                        context.GeometryShader.Set(debugNormals);

                        m.Render();

                        context.PixelShader.Set(prevPixelShader);
                        context.GeometryShader.Set(null);
                    }
                }

                //});

                // TRIANGLE
                //triangle.Render();

                //// QUAD
                //context.VertexShader.Set(tessellateVertexShader);
                //context.HullShader.Set(activeQuadTessellator);
                //context.DomainShader.Set(tessellateQuadDomainShader);

                //quad.Render();

                // BEZIER
                //context.VertexShader.Set(tessellateVertexShader);
                //context.HullShader.Set(activeBezierTessellator);
                //context.DomainShader.Set(tessellateBezierDomainShader);

                //bezier.Render();


                // AXIS GRID
                context.VertexShader.Set(vertexShader);
                context.HullShader.Set(null);
                context.DomainShader.Set(null);
                context.GeometryShader.Set(null);

                using (var prevPixelShader = context.PixelShader.Get())
                {
                    perMaterial.HasTexture  = 0;
                    perMaterial.UVTransform = Matrix.Identity;
                    context.UpdateSubresource(ref perMaterial, perMaterialBuffer);
                    context.PixelShader.Set(pixelShader);
                    perObject       = new ConstantBuffers.PerObject();
                    perObject.World = worldMatrix;
                    perObject.WorldInverseTranspose = Matrix.Transpose(Matrix.Invert(perObject.World));
                    perObject.WorldViewProjection   = perObject.World * viewProjection;
                    perObject.ViewProjection        = viewProjection;
                    perObject.Transpose();
                    context.UpdateSubresource(ref perObject, perObjectBuffer);
                    axisGrid.Render();
                    context.PixelShader.Set(prevPixelShader);
                }

                // Render FPS
                fps.Render();

                // Render instructions + position changes
                textRenderer.Render();

                // Present the frame
                Present();
            });
            #endregion
        }
        public override void Run()
        {
            #region Create renderers

            // Note: the renderers take care of creating their own
            // device resources and listen for DeviceManager.OnInitialize

            // Create a axis-grid renderer
            var axisGrid = ToDispose(new AxisGridRenderer());
            axisGrid.Initialize(this);

            // Create and initialize the mesh renderer
            var loadedMesh = Common.Mesh.LoadFromFile("Tree.cmo");
            loadedMesh.AddRange(Common.Mesh.LoadFromFile("Plane.cmo"));
            loadedMesh.AddRange(Common.Mesh.LoadFromFile("Cube.cmo"));
            //loadedMesh.AddRange(Common.Mesh.LoadFromFile("SkullLo.cmo"));
            loadedMesh.AddRange(Common.Mesh.LoadFromFile("SkullHi.cmo"));

            List<DisplacedMeshRenderer> meshes = new List<DisplacedMeshRenderer>();
            meshes.AddRange((from mesh in loadedMesh
                             select ToDispose(new DisplacedMeshRenderer(mesh))));
            foreach (var m in meshes) {
                m.Initialize(this);
                m.World = Matrix.Identity;
            }

            // Set the first animation as the current animation and start clock
            foreach (var m in meshes)
            {
                if (m.Mesh.Animations != null && m.Mesh.Animations.Any())
                    m.CurrentAnimation = m.Mesh.Animations.First().Value;
                m.Clock.Start();
            }

            var triangle = new TriangleRenderer();
            triangle.Initialize(this);

            // Create and initialize a Direct2D FPS text renderer
            var fps = ToDispose(new Common.FpsRenderer("Calibri", Color.CornflowerBlue, new Point(8, 8), 16));
            fps.Initialize(this);

            // Create and initialize a general purpose Direct2D text renderer
            // This will display some instructions and the current view and rotation offsets
            var textRenderer = ToDispose(new Common.TextRenderer("Calibri", Color.CornflowerBlue, new Point(8, 40), 12));
            textRenderer.Initialize(this);

            #endregion

            // Initialize the world matrix
            var worldMatrix = Matrix.Identity;

            // Set the camera position
            var cameraPosition = new Vector3(0, 0, 2);
            var cameraTarget = Vector3.Zero; // Looking at the origin 0,0,0
            var cameraUp = Vector3.UnitY; // Y+ is Up

            // Prepare matrices
            // Create the view matrix from our camera position, look target and up direction
            var viewMatrix = Matrix.LookAtRH(cameraPosition, cameraTarget, cameraUp);
            viewMatrix.TranslationVector += new Vector3(0, -0.98f, 0);

            // Create the projection matrix
            /* FoV 60degrees = Pi/3 radians */
            // Aspect ratio (based on window size), Near clip, Far clip
            var projectionMatrix = Matrix.PerspectiveFovRH((float)Math.PI / 3f, Width / (float)Height, 0.1f, 100f);

            // Maintain the correct aspect ratio on resize
            Window.Resize += (s, e) =>
            {
                projectionMatrix = Matrix.PerspectiveFovRH((float)Math.PI / 3f, Width / (float)Height, 0.1f, 100f);
            };

            #region Rotation and window event handlers

            // Create a rotation vector to keep track of the rotation
            // around each of the axes
            var rotation = new Vector3(0.0f, 0.0f, 0.0f);
            var tessellationFactor = 1f;
            var tessellationPartition = "Integer";
            var tessellationMethod = "Phong";
            var displacementScale = 0.02f;
            // We will call this action to update text
            // for the text renderer
            Action updateText = () =>
            {
                textRenderer.Text =
                    String.Format("Tessellation Factor: {0:#0.0} (+/- to change)"
                    + "\nPartitioning: {1} (F1,F2,F3,F4 to change)"
                    + "\nTessellation: {2} (F5,F6,F7)"
                    + "\nDisplacement: {3:#0.000} (Shift +/- to change)"
                    + "\nPress F to toggle wireframe | Shift+N toggle Normal Map | N show normals"
                    + "\nPress 1-8 to switch pixel shaders | Backspace to cycle meshes",
                        tessellationFactor,
                        tessellationPartition,
                        tessellationMethod,
                        displacementScale,
                        DeviceManager.Direct3DDevice.NativePointer);
            };

            Dictionary<Keys, bool> keyToggles = new Dictionary<Keys, bool>();
            keyToggles[Keys.Z] = false;
            keyToggles[Keys.F] = false;

            // Support keyboard/mouse input to rotate or move camera view
            var moveFactor = 0.02f; // how much to change on each keypress
            var shiftKey = false;
            var ctrlKey = false;
            var background = Color.White;
            var activeTriTessellator = tessellateTriIntegerShader;
            var activePnTriTessellator = pnTriIntegerShader;
            var usePhongTessellation = true;
            var usePNTessellation = false;
            var showNormals = false;
            var enableNormalMap = true;
            var meshIndex = 0;
            Window.KeyDown += (s, e) =>
            {
                var context = DeviceManager.Direct3DContext;

                shiftKey = e.Shift;
                ctrlKey = e.Control;

                switch (e.KeyCode)
                {
                    // WASD -> pans view
                    case Keys.A:
                        viewMatrix.TranslationVector += new Vector3(moveFactor * 2, 0f, 0f);
                        break;
                    case Keys.D:
                        viewMatrix.TranslationVector -= new Vector3(moveFactor * 2, 0f, 0f);
                        break;
                    case Keys.S:
                        if (shiftKey)
                            viewMatrix.TranslationVector += new Vector3(0f, moveFactor * 2, 0f);
                        else
                            viewMatrix.TranslationVector -= new Vector3(0f, 0f, 1) * moveFactor * 2;
                        break;
                    case Keys.W:
                        if (shiftKey)
                            viewMatrix.TranslationVector -= new Vector3(0f, moveFactor * 2, 0f);
                        else
                            viewMatrix.TranslationVector += new Vector3(0f, 0f, 1) * moveFactor * 2;
                        break;
                    // Up/Down and Left/Right - rotates around X / Y respectively
                    // (Mouse wheel rotates around Z)
                    case Keys.Down:
                        worldMatrix *= Matrix.RotationX(moveFactor);
                        rotation += new Vector3(moveFactor, 0f, 0f);
                        break;
                    case Keys.Up:
                        worldMatrix *= Matrix.RotationX(-moveFactor);
                        rotation -= new Vector3(moveFactor, 0f, 0f);
                        break;
                    case Keys.Left:
                        worldMatrix *= Matrix.RotationY(moveFactor);
                        rotation += new Vector3(0f, moveFactor, 0f);
                        break;
                    case Keys.Right:
                        worldMatrix *= Matrix.RotationY(-moveFactor);
                        rotation -= new Vector3(0f, moveFactor, 0f);
                        break;
                    case Keys.T:
                        fps.Show = !fps.Show;
                        textRenderer.Show = !textRenderer.Show;
                        break;
                    case Keys.B:
                        if (background == Color.White)
                        {
                            background = new Color(30, 30, 34);
                        }
                        else
                        {
                            background = Color.White;
                        }
                        break;
                    case Keys.G:
                        axisGrid.Show = !axisGrid.Show;
                        break;
                    case Keys.P:
                        // Pause or resume mesh animation
                        meshes.ForEach(m => {
                            if (m.Clock.IsRunning)
                                m.Clock.Stop();
                            else
                                m.Clock.Start();
                        });
                        break;
                    case Keys.X:
                        // To test for correct resource recreation
                        // Simulate device reset or lost.
                        System.Diagnostics.Debug.WriteLine(SharpDX.Diagnostics.ObjectTracker.ReportActiveObjects());
                        DeviceManager.Initialize(DeviceManager.Dpi);
                        System.Diagnostics.Debug.WriteLine(SharpDX.Diagnostics.ObjectTracker.ReportActiveObjects());
                        break;
                    case Keys.Z:
                        keyToggles[Keys.Z] = !keyToggles[Keys.Z];
                        if (keyToggles[Keys.Z])
                        {
                            context.PixelShader.Set(depthPixelShader);
                        }
                        else
                        {
                            context.PixelShader.Set(pixelShader);
                        }
                        break;
                    case Keys.F:
                        keyToggles[Keys.F] = !keyToggles[Keys.F];
                        RasterizerStateDescription rasterDesc;
                        if (context.Rasterizer.State != null)
                            rasterDesc = context.Rasterizer.State.Description;
                        else
                            rasterDesc = new RasterizerStateDescription()
                            {
                                CullMode = CullMode.None,
                                FillMode = FillMode.Solid
                            };
                        if (keyToggles[Keys.F])
                        {
                            rasterDesc.FillMode = FillMode.Wireframe;
                            context.Rasterizer.State = ToDispose(new RasterizerState(context.Device, rasterDesc));
                        }
                        else
                        {
                            rasterDesc.FillMode = FillMode.Solid;
                            context.Rasterizer.State = ToDispose(new RasterizerState(context.Device, rasterDesc));
                        }
                        break;
                    case Keys.N:
                        if (!shiftKey)
                            showNormals = !showNormals;
                        else
                            enableNormalMap = !enableNormalMap;

                        break;
                    case Keys.D1:
                        context.PixelShader.Set(pixelShader);
                        break;
                    case Keys.D2:
                        context.PixelShader.Set(lambertShader);
                        break;
                    case Keys.D3:
                        context.PixelShader.Set(phongShader);
                        break;
                    case Keys.D4:
                        context.PixelShader.Set(blinnPhongShader);
                        break;
                    case Keys.Add:
                        var multiple = 1.0f;
                        if (ctrlKey)
                            multiple = 3.0f;
                        if (!shiftKey)
                        {
                            tessellationFactor += 0.2f * multiple;
                            tessellationFactor = Math.Min(tessellationFactor, 64);
                        }
                        else
                        {
                            displacementScale += 0.005f * multiple;
                        }
                        break;
                    case Keys.Subtract:
                        multiple = 1.0f;
                        if (ctrlKey)
                            multiple = 3.0f;
                        if (!shiftKey)
                        {
                            tessellationFactor -= 0.2f * multiple;
                            tessellationFactor = Math.Max(tessellationFactor, 0);
                        }
                        else
                        {
                            displacementScale -= 0.005f * multiple;
                        }
                        break;
                    case Keys.F1:
                        tessellationPartition = "Integer";
                        activeTriTessellator = tessellateTriIntegerShader;
                        activePnTriTessellator = pnTriIntegerShader;
                        break;
                    case Keys.F2:
                        tessellationPartition = "Pow2";
                        activeTriTessellator = tessellateTriPow2Shader;
                        activePnTriTessellator = pnTriPow2Shader;
                        break;
                    case Keys.F3:
                        tessellationPartition = "Fractional Even";
                        activeTriTessellator = tessellateTriFractionalEvenShader;
                        activePnTriTessellator = pnTriFractionalEvenShader;
                        break;
                    case Keys.F4:
                        tessellationPartition = "Fractional Odd";
                        activeTriTessellator = tessellateTriFractionalOddShader;
                        activePnTriTessellator = pnTriFractionalOddShader;
                        break;
                    case Keys.F5:
                        usePhongTessellation = false;
                        usePNTessellation = false;
                        tessellationMethod = "Tri + displacement";
                        break;
                    case Keys.F6:
                        usePhongTessellation = true;
                        usePNTessellation = false;
                        tessellationMethod = "Phong + displacement";
                        break;
                    case Keys.F7:
                        usePhongTessellation = false;
                        usePNTessellation = true;
                        tessellationMethod = "PN-Triangle + displacement";
                        break;
                    case Keys.Back:
                        meshIndex = (meshIndex + 1) % meshes.Count;
                        break;
                }

                updateText();
            };
            Window.KeyUp += (s, e) =>
            {
                // Clear the shift/ctrl keys so they aren't sticky
                if (e.KeyCode == Keys.ShiftKey)
                    shiftKey = false;
                if (e.KeyCode == Keys.ControlKey)
                    ctrlKey = false;
            };
            Window.MouseWheel += (s, e) =>
            {
                if (shiftKey)
                {
                    // Zoom in/out
                    viewMatrix.TranslationVector += new Vector3(0f, 0f, (e.Delta / 120f) * moveFactor * 2);
                }
                else
                {
                    // rotate around Z-axis
                    viewMatrix *= Matrix.RotationZ((e.Delta / 120f) * moveFactor);
                    rotation += new Vector3(0f, 0f, (e.Delta / 120f) * moveFactor);
                }
                updateText();
            };

            var lastX = 0;
            var lastY = 0;

            Window.MouseDown += (s, e) =>
            {
                if (e.Button == MouseButtons.Left)
                {
                    lastX = e.X;
                    lastY = e.Y;
                }
            };

            Window.MouseMove += (s, e) =>
            {
                if (e.Button == MouseButtons.Left)
                {
                    var yRotate = lastX - e.X;
                    var xRotate = lastY - e.Y;
                    lastY = e.Y;
                    lastX = e.X;

                    // Mouse move changes
                    viewMatrix *= Matrix.RotationX(-xRotate * moveFactor);
                    viewMatrix *= Matrix.RotationY(-yRotate * moveFactor);

                    updateText();
                }
            };

            // Display instructions with initial values
            updateText();

            #endregion

            var clock = new System.Diagnostics.Stopwatch();
            clock.Start();

            #region Render loop

            // Create and run the render loop
            RenderLoop.Run(Window, () =>
            {
                // Start of frame:

                // Retrieve immediate context
                var context = DeviceManager.Direct3DContext;

                // Clear depth stencil view
                context.ClearDepthStencilView(DepthStencilView, DepthStencilClearFlags.Depth | DepthStencilClearFlags.Stencil, 1.0f, 0);
                // Clear render target view
                context.ClearRenderTargetView(RenderTargetView, background);

                // Create viewProjection matrix
                var viewProjection = Matrix.Multiply(viewMatrix, projectionMatrix);

                // Extract camera position from view
                var camPosition = Matrix.Transpose(Matrix.Invert(viewMatrix)).Column4;
                cameraPosition = new Vector3(camPosition.X, camPosition.Y, camPosition.Z);

                // If Keys.CtrlKey is down, auto rotate viewProjection based on time
                var time = clock.ElapsedMilliseconds / 1000.0f;

                var perFrame = new ConstantBuffers.PerFrame();
                perFrame.Light.Color = new Color(0.8f, 0.8f, 0.8f, 1.0f);
                var lightDir = Vector3.Transform(new Vector3(1f, -1f, -1f), worldMatrix);
                perFrame.Light.Direction = new Vector3(lightDir.X, lightDir.Y, lightDir.Z);// new Vector3(Vector3.Transform(new Vector3(1f, -1f, 1f), worldMatrix * worldRotation).ToArray().Take(3).ToArray());
                perFrame.CameraPosition = cameraPosition;
                perFrame.TessellationFactor = tessellationFactor;
                context.UpdateSubresource(ref perFrame, perFrameBuffer);

                // Render each object

                var perMaterial = new ConstantBuffers.PerMaterial();
                perMaterial.Ambient = new Color4(0.2f);
                perMaterial.Diffuse = Color.White;
                perMaterial.Emissive = new Color4(0);
                perMaterial.Specular = Color.White;
                perMaterial.SpecularPower = 20f;
                perMaterial.HasTexture = 0;
                perMaterial.UVTransform = Matrix.Identity;
                context.UpdateSubresource(ref perMaterial, perMaterialBuffer);

                var perObject = new ConstantBuffers.PerObject();

                // MESH
                context.VertexShader.Set(tessellateVertexShader);
                context.HullShader.Set(activeTriTessellator);
                if (usePhongTessellation)
                {
                    context.DomainShader.Set(tessellatePhongDomainShader);
                }
                else if (usePNTessellation)
                {
                    context.HullShader.Set(activePnTriTessellator);
                    context.DomainShader.Set(pnTriDomainShader);
                }
                else
                    context.DomainShader.Set(tessellateTriDomainShader);

                var m = meshes[meshIndex];
                //meshes.ForEach((m) =>
                //{
                // Provide the material constant buffer to the mesh renderer
                perObject.World = m.World * worldMatrix;
                perObject.WorldInverseTranspose = Matrix.Transpose(Matrix.Invert(perObject.World));
                perObject.WorldViewProjection = perObject.World * viewProjection;
                perObject.ViewProjection = viewProjection;
                perObject.Transpose();
                context.UpdateSubresource(ref perObject, perObjectBuffer);

                m.EnableNormalMap = enableNormalMap;
                m.DisplacementScale = displacementScale;
                m.DisplaceMidLevel = 0.5f;
                m.PerMaterialBuffer = perMaterialBuffer;
                m.PerArmatureBuffer = perArmatureBuffer;
                m.Render();

                if (showNormals)
                {
                    using (var prevPixelShader = context.PixelShader.Get())
                    {
                        perMaterial.HasTexture = 0;
                        perMaterial.UVTransform = Matrix.Identity;
                        context.UpdateSubresource(ref perMaterial, perMaterialBuffer);
                        context.PixelShader.Set(pixelShader);

                        context.GeometryShader.Set(debugNormals);

                        m.Render();

                        context.PixelShader.Set(prevPixelShader);
                        context.GeometryShader.Set(null);
                    }
                }

                //});

                // TRIANGLE
                //triangle.Render();

                //// QUAD
                //context.VertexShader.Set(tessellateVertexShader);
                //context.HullShader.Set(activeQuadTessellator);
                //context.DomainShader.Set(tessellateQuadDomainShader);

                //quad.Render();

                // BEZIER
                //context.VertexShader.Set(tessellateVertexShader);
                //context.HullShader.Set(activeBezierTessellator);
                //context.DomainShader.Set(tessellateBezierDomainShader);

                //bezier.Render();

                // AXIS GRID
                context.VertexShader.Set(vertexShader);
                context.HullShader.Set(null);
                context.DomainShader.Set(null);
                context.GeometryShader.Set(null);

                using (var prevPixelShader = context.PixelShader.Get())
                {
                    perMaterial.HasTexture = 0;
                    perMaterial.UVTransform = Matrix.Identity;
                    context.UpdateSubresource(ref perMaterial, perMaterialBuffer);
                    context.PixelShader.Set(pixelShader);
                    perObject = new ConstantBuffers.PerObject();
                    perObject.World = worldMatrix;
                    perObject.WorldInverseTranspose = Matrix.Transpose(Matrix.Invert(perObject.World));
                    perObject.WorldViewProjection = perObject.World * viewProjection;
                    perObject.ViewProjection = viewProjection;
                    perObject.Transpose();
                    context.UpdateSubresource(ref perObject, perObjectBuffer);
                    axisGrid.Render();
                    context.PixelShader.Set(prevPixelShader);
                }

                // Render FPS
                fps.Render();

                // Render instructions + position changes
                textRenderer.Render();

                // Present the frame
                Present();
            });
            #endregion
        }