irrlicht锁纹理和渲染目标

 

// ! lock function
void *  CD3D9Texture:: lock ( bool  readOnly, u32 mipmapLevel)
{
     if  ( ! Texture)
         return   0 ;

    MipLevelLocked = mipmapLevel;
    HRESULT hr;
    D3DLOCKED_RECT rect;
     if ( ! IsRenderTarget)
    {
        hr  =  Texture -> LockRect(mipmapLevel,  & rect,  0 , readOnly ? D3DLOCK_READONLY: 0 );
         if  (FAILED(hr))
        {
            os::Printer::log( " Could not lock DIRECT3D9 Texture. " , ELL_ERROR);
             return   0 ;
        }
    }
     else
    {
         if  ( ! RTTSurface)
        {
             //  Make RTT surface large enough for all miplevels (including 0)
            D3DSURFACE_DESC desc;
            Texture -> GetLevelDesc( 0 ,  & desc);
            hr  =  Device -> CreateOffscreenPlainSurface(desc.Width, desc.Height, desc.Format, D3DPOOL_SYSTEMMEM,  & RTTSurface,  0 );
             if  (FAILED(hr))
            {
                os::Printer::log( " Could not lock DIRECT3D9 Texture " ,  " Offscreen surface creation failed. " , ELL_ERROR);
                 return   0 ;
            }
        }

        IDirect3DSurface9  * surface  =   0 ;
        hr  =  Texture -> GetSurfaceLevel(mipmapLevel,  & surface);
         if  (FAILED(hr))
        {
            os::Printer::log( " Could not lock DIRECT3D9 Texture " ,  " Could not get surface. " , ELL_ERROR);
             return   0 ;
        }
        hr  =  Device -> GetRenderTargetData(surface, RTTSurface);
        surface -> Release();
         if (FAILED(hr))
        {
            os::Printer::log( " Could not lock DIRECT3D9 Texture " ,  " Data copy failed. " , ELL_ERROR);
             return   0 ;
        }
        hr  =  RTTSurface -> LockRect( & rect,  0 , readOnly ? D3DLOCK_READONLY: 0 );
         if (FAILED(hr))
        {
            os::Printer::log( " Could not lock DIRECT3D9 Texture " ,  " LockRect failed. " , ELL_ERROR);
             return   0 ;
        }
    }
     return  rect.pBits;
}