[转]DirectX9获取深度缓存值

http://www.cppblog.com/xiaowugui/archive/2010/01/06/104962.html

   DirectX中，如何获取深度值，然后将它存储在一个txt文件中？其实只要修改两个地方：
   第一个地方是：创建Direct3D设备时，将D3DPRESENT_PARAMETERS类型表示变量的AutoDepthStencilFormat设置为D3DFMT_D32F_LOCKABLE，代码如下：

    D3DPRESENT_PARAMETERS d3dpp;
    d3dpp.BackBufferWidth            = width;
    d3dpp.BackBufferHeight           = height;
    d3dpp.BackBufferFormat           = D3DFMT_A8R8G8B8;
    d3dpp.BackBufferCount            = 1;
    d3dpp.MultiSampleType            = D3DMULTISAMPLE_NONE;
    d3dpp.MultiSampleQuality         = 0;
    d3dpp.SwapEffect                   = D3DSWAPEFFECT_DISCARD; 
    d3dpp.hDeviceWindow              = hwnd;
    d3dpp.Windowed                     = windowed;
    d3dpp.EnableAutoDepthStencil     = true; 
    d3dpp.AutoDepthStencilFormat     = D3DFMT_D32F_LOCKABLE;    // 16位总不行
    d3dpp.Flags                      = 0;
    d3dpp.FullScreen_RefreshRateInHz = D3DPRESENT_RATE_DEFAULT;
    d3dpp.PresentationInterval       = D3DPRESENT_INTERVAL_IMMEDIATE;

第二个地方是：设置锁定缓存表面，并进行读写的代码：

            // 获取深度模板表面
       HRESULT hr = Device->GetDepthStencilSurface( &pZBuffer );
            if ( FAILED( hr ) ) { 
                MessageBox( NULL, "GetDepthStencilSurface failure", 0, 0 ); 
            }
            
            // 打开文件
            pFile = fopen( "ZBuffer.txt", "w" );
            if ( pFile == NULL ) { 
                MessageBox( NULL, "shit", NULL, NULL); 
            }
            
            // 获取表面特性
            D3DSURFACE_DESC surfaceDesc;
            pZBuffer->GetDesc( &surfaceDesc );

            // 锁定表面
            D3DLOCKED_RECT lockRect;
            hr = pZBuffer->LockRect( &lockRect, NULL, D3DLOCK_READONLY );
            if ( FAILED( hr ) ) { 
                MessageBox( NULL, "GetDepthStencilSurface", 0, 0 ); 
            }
            
            // 获取指向表面区域指针
            float* pData = (float*)lockRect.pBits;

            // 将深度信息输出到文件中
            for (int y = 0; y < surfaceDesc.Height; ++y ) {
                for (int x = 0; x < surfaceDesc.Width; ++x ) {
                    int index = y * lockRect.Pitch / 4 + x;
                    fprintf( pFile, "%f  ", pData[index] );
                }
                fprintf( pFile,"\n");
            }
            
            // 解锁表面锁定
            pZBuffer->UnlockRect();    
            
            // 释放接口和文件
            pZBuffer->Release();
            fclose( pFile );