private void InitializeGeometryBuffers()
        {
            PassDescription PassDesc = technique.GetPassByIndex(0).Description;

            vertexLayout = device.CreateInputLayout(
                inputLayouts,
                PassDesc.InputAssemblerInputSignature,
                PassDesc.InputAssemblerInputSignatureSize
                );

            // Set the input layout
            device.IA.InputLayout = vertexLayout;


            BufferDescription bd = new BufferDescription();

            bd.Usage                        = Usage.Default;
            bd.ByteWidth                    = (uint)Marshal.SizeOf(vertexArray.s_VertexArray);
            bd.BindingOptions               = BindingOptions.VertexBuffer;
            bd.CpuAccessOptions             = CpuAccessOptions.None;
            bd.MiscellaneousResourceOptions = MiscellaneousResourceOptions.None;

            IntPtr ptr = Marshal.AllocHGlobal(Marshal.SizeOf(vertexArray.s_VertexArray));

            Marshal.StructureToPtr(vertexArray.s_VertexArray, ptr, true);
            SubresourceData initData = new SubresourceData {
                SystemMemory = ptr
            };

            vertexBuffer = device.CreateBuffer(bd, initData);
            Marshal.FreeHGlobal(ptr);

            // Set vertex buffer
            uint stride = (uint)Marshal.SizeOf(typeof(SimpleVertex));
            uint offset = 0;

            device.IA.SetVertexBuffers(
                0, // StartSlot
                new[] { vertexBuffer },
                new[] { stride },
                new[] { offset });

            bd.Usage                        = Usage.Default;
            bd.ByteWidth                    = (uint)Marshal.SizeOf(vertexArray.s_FacesIndexArray);
            bd.BindingOptions               = BindingOptions.IndexBuffer;
            bd.CpuAccessOptions             = CpuAccessOptions.None;
            bd.MiscellaneousResourceOptions = MiscellaneousResourceOptions.None;

            ptr = Marshal.AllocHGlobal(Marshal.SizeOf(vertexArray.s_FacesIndexArray));
            Marshal.StructureToPtr(vertexArray.s_FacesIndexArray, ptr, true);

            initData.SystemMemory = ptr;
            facesIndexBuffer      = device.CreateBuffer(bd, initData);

            // Set primitive topology
            device.IA.PrimitiveTopology = PrimitiveTopology.TriangleList;
        }
        private void InitVertexLayout()
        {
            // Define the input layout
            // The layout determines the stride in the vertex buffer,
            // so changes in layout need to be reflected in SetVertexBuffers
            InputElementDescription[] layout =
            {
                new InputElementDescription()
                {
                    SemanticName         = "POSITION",
                    SemanticIndex        = 0,
                    Format               = Format.R32G32B32Float,
                    InputSlot            = 0,
                    AlignedByteOffset    = 0,
                    InputSlotClass       = InputClassification.PerVertexData,
                    InstanceDataStepRate = 0
                },
                new InputElementDescription()
                {
                    SemanticName         = "TEXCOORD",
                    SemanticIndex        = 0,
                    Format               = Format.R32G32Float,
                    InputSlot            = 0,
                    AlignedByteOffset    = 12,
                    InputSlotClass       = InputClassification.PerVertexData,
                    InstanceDataStepRate = 0
                },
            };

            PassDescription passDesc = technique.GetPassByIndex(0).Description;

            vertexLayout = device.CreateInputLayout(
                layout,
                passDesc.InputAssemblerInputSignature,
                passDesc.InputAssemblerInputSignatureSize);

            device.IA.InputLayout = vertexLayout;
        }
        void CreateDeviceResources()
        {
            uint width  = (uint)host.ActualWidth;
            uint height = (uint)host.ActualHeight;

            // If we don't have a device, need to create one now and all
            // accompanying D3D resources.
            CreateDevice();

            Factory dxgiFactory = Factory.Create();

            SwapChainDescription swapDesc = new SwapChainDescription
            {
                BufferDescription = new ModeDescription
                {
                    Width       = width, Height = height,
                    Format      = Format.R8G8B8A8UNorm,
                    RefreshRate = new Rational {
                        Numerator = 60, Denominator = 1
                    }
                },
                SampleDescription = new SampleDescription {
                    Count = 1, Quality = 0
                },
                BufferUsage        = UsageOptions.RenderTargetOutput,
                BufferCount        = 1,
                OutputWindowHandle = host.Handle,
                Windowed           = true
            };

            swapChain = dxgiFactory.CreateSwapChain(
                device, swapDesc);

            // Create rasterizer state object
            RasterizerDescription rsDesc = new RasterizerDescription();

            rsDesc.AntiAliasedLineEnable = false;
            rsDesc.CullMode              = CullMode.None;
            rsDesc.DepthBias             = 0;
            rsDesc.DepthBiasClamp        = 0;
            rsDesc.DepthClipEnable       = true;
            rsDesc.FillMode              = D3D10.FillMode.Solid;
            rsDesc.FrontCounterclockwise = false; // Must be FALSE for 10on9
            rsDesc.MultisampleEnable     = false;
            rsDesc.ScissorEnable         = false;
            rsDesc.SlopeScaledDepthBias  = 0;

            rasterizerState = device.CreateRasterizerState(
                rsDesc);

            device.RS.State = rasterizerState;

            // If we don't have a D2D render target, need to create all of the resources
            // required to render to one here.
            // Ensure that nobody is holding onto one of the old resources
            device.OM.RenderTargets = new OutputMergerRenderTargets(new RenderTargetView[] { null });

            InitializeDepthStencil(width, height);

            // Create views on the RT buffers and set them on the device
            RenderTargetViewDescription renderDesc = new RenderTargetViewDescription();

            renderDesc.Format        = Format.R8G8B8A8UNorm;
            renderDesc.ViewDimension = RenderTargetViewDimension.Texture2D;

            Texture2DRenderTargetView renderView = renderDesc.Texture2D;

            renderView.MipSlice  = 0;
            renderDesc.Texture2D = renderView;

            using (D3DResource spBackBufferResource = swapChain.GetBuffer <D3DResource>(0))
            {
                renderTargetView = device.CreateRenderTargetView(
                    spBackBufferResource,
                    renderDesc);
            }

            device.OM.RenderTargets = new OutputMergerRenderTargets(new RenderTargetView[] { renderTargetView }, depthStencilView);

            SetViewport(width, height);


            // Create a D2D render target which can draw into the surface in the swap chain
            RenderTargetProperties props =
                new RenderTargetProperties(
                    RenderTargetType.Default, new PixelFormat(Format.Unknown, AlphaMode.Premultiplied),
                    96, 96, RenderTargetUsages.None, FeatureLevel.Default);

            // Allocate a offscreen D3D surface for D2D to render our 2D content into
            Texture2DDescription tex2DDescription = new Texture2DDescription
            {
                ArraySize                    = 1,
                BindingOptions               = BindingOptions.RenderTarget | BindingOptions.ShaderResource,
                CpuAccessOptions             = CpuAccessOptions.None,
                Format                       = Format.R8G8B8A8UNorm,
                Height                       = 4096,
                Width                        = 512,
                MipLevels                    = 1,
                MiscellaneousResourceOptions = MiscellaneousResourceOptions.None,
                SampleDescription            = new SampleDescription {
                    Count = 1, Quality = 0
                },
                Usage = Usage.Default
            };

            offscreenTexture = device.CreateTexture2D(tex2DDescription);

            using (Surface dxgiSurface = offscreenTexture.GraphicsSurface)
            {
                // Create a D2D render target which can draw into our offscreen D3D surface
                renderTarget = d2DFactory.CreateGraphicsSurfaceRenderTarget(
                    dxgiSurface,
                    props);
            }

            PixelFormat alphaOnlyFormat = new PixelFormat(Format.A8UNorm, AlphaMode.Premultiplied);

            opacityRenderTarget = renderTarget.CreateCompatibleRenderTarget(CompatibleRenderTargetOptions.None,
                                                                            alphaOnlyFormat);

            // Load pixel shader
            // Open precompiled vertex shader
            // This file was compiled using DirectX's SDK Shader compilation tool:
            // fxc.exe /T fx_4_0 /Fo SciFiText.fxo SciFiText.fx
            shader = LoadResourceShader(device, "SciFiTextDemo.SciFiText.fxo");

            // Obtain the technique
            technique = shader.GetTechniqueByName("Render");

            // Obtain the variables
            worldMatrixVariable     = shader.GetVariableByName("World").AsMatrix;
            viewMatrixVariable      = shader.GetVariableByName("View").AsMatrix;
            projectionMarixVariable = shader.GetVariableByName("Projection").AsMatrix;
            diffuseVariable         = shader.GetVariableByName("txDiffuse").AsShaderResource;

            // Create the input layout
            PassDescription passDesc = new PassDescription();

            passDesc = technique.GetPassByIndex(0).Description;

            vertexLayout = device.CreateInputLayout(
                inputLayoutDescriptions,
                passDesc.InputAssemblerInputSignature,
                passDesc.InputAssemblerInputSignatureSize
                );

            // Set the input layout
            device.IA.InputLayout = vertexLayout;

            IntPtr verticesDataPtr = Marshal.AllocHGlobal(Marshal.SizeOf(VertexArray.VerticesInstance));

            Marshal.StructureToPtr(VertexArray.VerticesInstance, verticesDataPtr, true);

            BufferDescription bd = new BufferDescription();

            bd.Usage                        = Usage.Default;
            bd.ByteWidth                    = (uint)Marshal.SizeOf(VertexArray.VerticesInstance);
            bd.BindingOptions               = BindingOptions.VertexBuffer;
            bd.CpuAccessOptions             = CpuAccessOptions.None;
            bd.MiscellaneousResourceOptions = MiscellaneousResourceOptions.None;

            SubresourceData InitData = new SubresourceData {
                SystemMemory = verticesDataPtr
            };

            vertexBuffer = device.CreateBuffer(bd, InitData);

            Marshal.FreeHGlobal(verticesDataPtr);

            // Set vertex buffer
            uint stride = (uint)Marshal.SizeOf(typeof(SimpleVertex));
            uint offset = 0;

            device.IA.SetVertexBuffers(
                0,
                new D3DBuffer[] { vertexBuffer },
                new uint[] { stride },
                new uint[] { offset }
                );

            IntPtr indicesDataPtr = Marshal.AllocHGlobal(Marshal.SizeOf(VertexArray.IndicesInstance));

            Marshal.StructureToPtr(VertexArray.IndicesInstance, indicesDataPtr, true);

            bd.Usage                        = Usage.Default;
            bd.ByteWidth                    = (uint)Marshal.SizeOf(VertexArray.IndicesInstance);
            bd.BindingOptions               = BindingOptions.IndexBuffer;
            bd.CpuAccessOptions             = CpuAccessOptions.None;
            bd.MiscellaneousResourceOptions = MiscellaneousResourceOptions.None;

            InitData.SystemMemory = indicesDataPtr;

            facesIndexBuffer = device.CreateBuffer(
                bd,
                InitData
                );

            Marshal.FreeHGlobal(indicesDataPtr);

            // Set primitive topology
            device.IA.PrimitiveTopology = PrimitiveTopology.TriangleList;

            // Convert the D2D texture into a Shader Resource View
            textureResourceView = device.CreateShaderResourceView(
                offscreenTexture);

            // Initialize the world matrices
            worldMatrix = Matrix4x4F.Identity;

            // Initialize the view matrix
            Vector3F Eye = new Vector3F(0.0f, 0.0f, 13.0f);
            Vector3F At  = new Vector3F(0.0f, -3.5f, 45.0f);
            Vector3F Up  = new Vector3F(0.0f, 1.0f, 0.0f);

            viewMatrix = Camera.MatrixLookAtLH(Eye, At, Up);

            // Initialize the projection matrix
            projectionMatrix = Camera.MatrixPerspectiveFovLH(
                (float)Math.PI * 0.1f,
                width / (float)height,
                0.1f,
                100.0f);

            // Update Variables that never change
            viewMatrixVariable.Matrix = viewMatrix;

            projectionMarixVariable.Matrix = projectionMatrix;

            GradientStop[] gradientStops =
            {
                new GradientStop(0.0f, new ColorF(GetColorValues(System.Windows.Media.Colors.Yellow))),
                new GradientStop(1.0f, new ColorF(GetColorValues(System.Windows.Media.Colors.Black)))
            };

            GradientStopCollection spGradientStopCollection = renderTarget.CreateGradientStopCollection(
                gradientStops, Gamma.StandardRgb, ExtendMode.Clamp);

            // Create a linear gradient brush for text
            textBrush = renderTarget.CreateLinearGradientBrush(
                new LinearGradientBrushProperties(new Point2F(0, 0), new Point2F(0, -2048)),
                spGradientStopCollection
                );
        }