SlimDX和WPF的合作应用

1.首先定义一个DX操作类

     using System;
     using SlimDX;
     using SlimDX.Direct3D9;
     using System.Windows.Interop;
     using System.Windows.Media;

     public class DX
     {
         private enum DirectXStatus
         {
             Available,
             Unavailable_RemoteSession,
             Unavailable_LowTier,
             Unavailable_MissingDirectX,
             Unavailable_Unknown
         };

         public static Device Device { get; private set; }
         public static bool Available { get { return DX.Device != null; } }// = false;

         private static DX _dx;
         private static DirectXStatus _status = DirectXStatus.Unavailable_Unknown;
         private static string _statusMessage = "";

         [System.Runtime.InteropServices.DllImport("user32")]
         private static extern int GetSystemMetrics(int smIndex);
         private const int SM_REMOTESESSION = 0x1000;

         // device settings
         private const Format _adapterFormat = Format.X8R8G8B8;
         private const Format _backbufferFormat = Format.A8R8G8B8;
         private const Format _depthStencilFormat = Format.D16;
         private static CreateFlags _createFlags = CreateFlags.Multithreaded | CreateFlags.FpuPreserve;

         private Direct3D _d3d;

         private DX()
         {
             initD3D();
             if (_d3d != null)
                 initDevice();
             //if (!DX.Available)
             //    MessageBox.Show("DirectX硬件加速不可用！\n\n" + _statusMessage, "", MessageBoxButton.OK, MessageBoxImage.Warning);
         }

         ~DX()
         {
             if (DX.Device != null)
                 if (!DX.Device.Disposed)
                     DX.Device.Dispose();
             if (_d3d != null)
                 if (!_d3d.Disposed)
                     _d3d.Dispose();
         }

         public static void Init()
         {
             if (_dx == null)
                 _dx = new DX();
         }

         private void initD3D()
         {
             if (_d3d != null)
                 return;

             _status = DirectXStatus.Unavailable_Unknown;

             //// assume that we can't run at all under terminal services
             if (GetSystemMetrics(SM_REMOTESESSION) != )
             {
                 _status = DirectXStatus.Unavailable_RemoteSession;
                 return;
             }

             int renderingTier = (RenderCapability.Tier >> );
             if (renderingTier < )
             {
                 _status = DirectXStatus.Unavailable_LowTier;
                 _statusMessage = "low tier";
                 return;//注意：发现某些集成显卡，在这里出去！！
             }

             try
             {
                 _d3d = new Direct3DEx();
             }
             catch
             {
                 try
                 {
                     _d3d = new Direct3D();
                 }
                 catch (Direct3DX9NotFoundException dfe)
                 {
                     _status = DirectXStatus.Unavailable_MissingDirectX;
                     _statusMessage = "Direct3DX9 Not Found\n" + dfe.Message;
                     return;
                 }
                 catch (Exception e)
                 {
                     _status = DirectXStatus.Unavailable_Unknown;
                     _statusMessage = e.Message;
                     return;
                 }
             }

             bool ok;
             Result result;

             ok = _d3d.CheckDeviceType(, DeviceType.Hardware, _adapterFormat, _backbufferFormat, true, out result);
             if (!ok)
             {
                 //Debug.WriteLine("*** failed to CheckDeviceType");
                 //MessageBox.Show("Failed to CheckDeviceType");
                 return;
             }

             ok = _d3d.CheckDepthStencilMatch(, DeviceType.Hardware, _adapterFormat, _backbufferFormat, _depthStencilFormat, out result);
             if (!ok)
             {
                 //Debug.WriteLine("*** failed to CheckDepthStencilMatch");
                 _statusMessage = "Failed to CheckDepthStencilMatch";
                 return;
             }

             Capabilities deviceCaps = _d3d.GetDeviceCaps(, DeviceType.Hardware);
             if ((deviceCaps.DeviceCaps & DeviceCaps.HWTransformAndLight) != )
                 _createFlags |= CreateFlags.HardwareVertexProcessing;
             else
                 _createFlags |= CreateFlags.SoftwareVertexProcessing;

             _status = DirectXStatus.Available;
         }

         private void initDevice()
         {
             if (_status != DirectXStatus.Available)
                 return;

             HwndSource hwnd = new HwndSource(, , , , , , , "SlimDX_Wnd", IntPtr.Zero);
             PresentParameters pp = new PresentParameters();
             //pp.SwapEffect = SwapEffect.Copy;
             //pp.DeviceWindowHandle = hwnd.Handle;
             pp.Windowed = true;
             pp.PresentFlags = PresentFlags.Video;
             pp.SwapEffect = SwapEffect.Discard;
             //pp.BackBufferCount = 1;
             //pp.BackBufferWidth = 320;
             //pp.BackBufferHeight = 240;
             //pp.BackBufferFormat = _backbufferFormat;
             //pp.AutoDepthStencilFormat = _depthStencilFormat;
             try
             {
                 DeviceType deviceType = DeviceType.Hardware;
                 if (_d3d is Direct3DEx)
                     DX.Device = new DeviceEx((Direct3DEx)_d3d, , deviceType, hwnd.Handle, _createFlags, pp);
                 else
                     DX.Device = new Device(_d3d, , deviceType, hwnd.Handle, _createFlags, pp);
             }
             catch (Exception ex)
             {
                 //Debug.WriteLine("Exception in Direct3DReset " + ex.StackTrace);
                 //Debug.WriteLine("Exception in Direct3DReset " + ex.Message);
             }
         }
     }

2.定义准备显卡硬件，和释放显卡硬件方法

定义一些变量

    　　 /// <summary>
        /// 离屏表面
        /// </summary>
        private Surface _offscrn;
        /// <summary>
        /// 交换链
        /// </summary>
        private SwapChain _swapChain;
        private D3DImage _d3dImage = null;    

 　　　　　/// <summary>
         /// 准备DirectX显卡硬件
         /// </summary>
         private bool prepareHardware(VideoFormat videoFormat, int videoWidth, int videoHeight)//, VideoFormat videoFormat)
         {
             if (!DX.Available)
                 return true;

             try
             {
                 SlimDX.Direct3D9.Format format = SlimDX.Direct3D9.Format.A8R8G8B8;
                 if (videoFormat == VideoFormat.Yuv420)
                     format = (SlimDX.Direct3D9.Format)0x32315659;
                 if (_offscrn != null)
                     if (videoWidth == _offscrn.Description.Width && videoHeight == _offscrn.Description.Height && _offscrn.Description.Format == format)
                         return true;

                 releaseHardware();
                 _offscrn = Surface.CreateOffscreenPlain(DX.Device, videoWidth, videoHeight, format, Pool.Default);
                 PresentParameters pp = new PresentParameters();
                 pp.Windowed = true;
                 pp.PresentFlags = PresentFlags.Video;
                 pp.SwapEffect = SwapEffect.Discard;
                 pp.BackBufferCount = ;
                 pp.BackBufferWidth = videoWidth;
                 pp.BackBufferHeight = videoHeight;
                 _swapChain = new SwapChain(DX.Device, pp);
                 return true;
             }
             catch
             {
                 return false;
             }
         }
         /// <summary>
         /// 释放DirectX显卡硬件
         /// </summary>
         private void releaseHardware()
         {
             if (!DX.Available)
                 return;
             if (_offscrn != null)
                 if (!_offscrn.Disposed)
                     _offscrn.Dispose();
             _offscrn = null;
             if (_swapChain != null)
                 if (!_swapChain.Disposed)
                     _swapChain.Dispose();
             _swapChain = null;
         }

3.

 private void drawFrame(VideoFormat videoFormat, int width, int height, IntPtr Y, IntPtr U, IntPtr V)
        {
            if (!prepareHardware(videoFormat, width, height))
                return;
            if (_swapChain == null)
                return;

            DataRectangle dr = _offscrn.LockRectangle(LockFlags.None);//在离屏表面上锁定一个矩形
            drawYuv420(width, height, Y, U, V, dr.Data.DataPointer, dr.Pitch);//DataPointer 内部指针指向当前流的存储备份; Pitch 两个连续的行之间的数据的字节数
            _offscrn.UnlockRectangle();//解锁矩形
            using (Surface bb = _swapChain.GetBackBuffer())//从交换链中检索一个后台缓冲区
            {
                System.Drawing.Rectangle rect = new System.Drawing.Rectangle(, , bb.Description.Width, bb.Description.Height);
                _swapChain.Device.StretchRectangle(_offscrn, rect, bb, rect, TextureFilter.None);//将后台缓冲区的内容交换到前台缓冲区
                _swapChain.Device.Present();//呈现后台缓冲区序列中下一个后台缓冲区的内容

                _d3dImage.Lock();
                _d3dImage.SetBackBuffer(D3DResourceType.IDirect3DSurface9, bb.ComPointer);
                _d3dImage.AddDirtyRect(new Int32Rect(, , _d3dImage.PixelWidth, _d3dImage.PixelHeight));
                _d3dImage.Unlock();
            }
        }

        private void drawYuv420(int width, int height, IntPtr Y, IntPtr U, IntPtr V, IntPtr dest, int pitch)
        {
            IntPtr py = dest;
            IntPtr pv = py + (pitch * height);
            IntPtr pu = pv + ((pitch * height) / );
            int w2 = width / , pitch2 = pitch / ;
            for (int y = ; y < height; y++)
            {
                CopyMemory(py, Y + y * width, (uint)width);
                py += pitch;
                if ((y & ) != )
                    continue;
                int offset = y /  * w2;
                CopyMemory(pu, U + offset, (uint)w2);
                CopyMemory(pv, V + offset, (uint)w2);
                pu += pitch2;
                pv += pitch2;
            }
        }
[DllImport("kernel32.dll", EntryPoint = "RtlMoveMemory")]
        private static extern void CopyMemory(IntPtr Destination, IntPtr Source, uint Length);