4.6 Debugging Direct3D Applications

超、凢脫俗 2021-11-16 07:02 191阅读 0赞

## 4.6 Debugging Direct3D Applications ##

In order to shorten the code and minimize distractions, we omit most error handling in this book. However, we do implement a macro to check the HRESULT return codes returned by many Direct3D functions. Our macro is defined as follows in *d3dUtil.h*:

1 \#if  defined(DEBUG) | defined(\_DEBUG)   
  2  \#ifndef HR  
  3  \#define  HR(x) \\   
  4  \{ \\  
  5  HRESULT hr  =  (x); \\  
  6  if (FAILED(hr)) \\  
  7  \{ \\  
  8  DXTrace(\_\_FILE\_\_, (DWORD)\_\_LINE\_\_, hr, L\#x,  true ); \\  
  9  \} \\  
 10  \}  
 11  \#endif   
 12  \#else   
 13  \#ifndef HR  
 14  \#define  HR(x) (x)   
 15  \#endif   
 16  \#endif

If the returned function’s return code indicates failure, then we pass the return code into the DXTrace function ( \#include <dxerr.h>) and link *dxerr.lib*:

HRESULT WINAPI DXTraceW( const  char \*  strFile, DWORD dwLine,  
HRESULT hr,  const  WCHAR \*  strMsg, BOOL bPopMsgBox);

This function displays a nice message box indicating the file and line number where the error occurred, as well as a textual description of the error and the name of the function that generated the error; Figure 4.10 shows an example. Note that if you specify false for the last parameter of DXTrace, then instead of a message box, the debug info will be output to the Visual C++ output window. Observe that the macro HR does nothing if we are not in debug mode. Also, HR must be a macro and not a function; otherwise \_\_FILE\_\_ and \_\_LINE\_\_ would refer to the file and line of the function implementation instead of the file and line where the function HR was called.

![2010092021420527.jpg][]  
Figure 4.10: The message box displayed by the DXTrace function if a Direct3D function returns an error.

Now we just use this macro to surround a Direct3D function that returns an HRESULT as this example shows:

HR(D3DX10CreateShaderResourceViewFromFile(md3dDevice,
          L"grass.dds", 0, 0, &mGrassTexRV, 0 ));

This works well for debugging our demos, but a real application should handle errors more robustly.

Note The L\#x turns the HR macro’s argument token into a Unicode string. In this way, we can output to the message box the function call that caused the error.

转载于:https://www.cnblogs.com/seanyou/archive/2010/09/20/1831427.html

[2010092021420527.jpg]: /images/20211116/1883f3ce122c4f4eaea5dcd2fe4215fa.png