dxutmisc.cpp

在GPU上实现数值模拟技术（线性方程组）的通用架构

//--------------------------------------------------------------------------------------
// File: DXUTMisc.cpp
//
// Shortcut macros and functions for using DX objects
//
// Copyright (c) Microsoft Corporation. All rights reserved
//--------------------------------------------------------------------------------------
#include "dxstdafx.h"

//--------------------------------------------------------------------------------------
// Global/Static Members
//--------------------------------------------------------------------------------------
CDXUTResourceCache& DXUTGetGlobalResourceCache()
{
    // Using an accessor function gives control of the construction order
    static CDXUTResourceCache cache;
    return cache;
}
CDXUTTimer* DXUTGetGlobalTimer()
{
    // Using an accessor function gives control of the construction order
    static CDXUTTimer timer;
    return &timer;
}


//--------------------------------------------------------------------------------------
// Internal functions forward declarations
//--------------------------------------------------------------------------------------
bool DXUTFindMediaSearchTypicalDirs( WCHAR* strSearchPath, int cchSearch, LPCWSTR strLeaf, WCHAR* strExePath, WCHAR* strExeName, LPCWSTR strMediaDir );
bool DXUTFindMediaSearchParentDirs( WCHAR* strSearchPath, int cchSearch, WCHAR* strStartAt, WCHAR* strLeafName );


//--------------------------------------------------------------------------------------
CDXUTTimer::CDXUTTimer()
{
    m_bUsingQPF         = false;
    m_bTimerStopped     = true;
    m_llQPFTicksPerSec  = 0;

    m_llStopTime        = 0;
    m_llLastElapsedTime = 0;
    m_llBaseTime        = 0;

    // Use QueryPerformanceFrequency() to get frequency of timer.  
    LARGE_INTEGER qwTicksPerSec;
    m_bUsingQPF = (bool) (QueryPerformanceFrequency( &qwTicksPerSec ) != 0);
    m_llQPFTicksPerSec = qwTicksPerSec.QuadPart;
}


//--------------------------------------------------------------------------------------
void CDXUTTimer::Reset()
{
    if( !m_bUsingQPF )
        return;

    // Get either the current time or the stop time
    LARGE_INTEGER qwTime;
    if( m_llStopTime != 0 )
        qwTime.QuadPart = m_llStopTime;
    else
        QueryPerformanceCounter( &qwTime );

    m_llBaseTime        = qwTime.QuadPart;
    m_llLastElapsedTime = qwTime.QuadPart;
    m_llStopTime        = 0;
    m_bTimerStopped     = FALSE;
}


//--------------------------------------------------------------------------------------
void CDXUTTimer::Start()
{
    if( !m_bUsingQPF )
        return;

    // Get either the current time or the stop time
    LARGE_INTEGER qwTime;
    if( m_llStopTime != 0 )
        qwTime.QuadPart = m_llStopTime;
    else
        QueryPerformanceCounter( &qwTime );

    if( m_bTimerStopped )
        m_llBaseTime += qwTime.QuadPart - m_llStopTime;
    m_llStopTime = 0;
    m_llLastElapsedTime = qwTime.QuadPart;
    m_bTimerStopped = FALSE;
}


//--------------------------------------------------------------------------------------
void CDXUTTimer::Stop()
{
    if( !m_bUsingQPF )
        return;

    if( !m_bTimerStopped )
    {
        // Get either the current time or the stop time
        LARGE_INTEGER qwTime;
        if( m_llStopTime != 0 )
            qwTime.QuadPart = m_llStopTime;
        else
            QueryPerformanceCounter( &qwTime );

        m_llStopTime = qwTime.QuadPart;
        m_llLastElapsedTime = qwTime.QuadPart;
        m_bTimerStopped = TRUE;
    }
}


//--------------------------------------------------------------------------------------
void CDXUTTimer::Advance()
{
    if( !m_bUsingQPF )
        return;

    m_llStopTime += m_llQPFTicksPerSec/10;
}


//--------------------------------------------------------------------------------------
double CDXUTTimer::GetAbsoluteTime()
{
    if( !m_bUsingQPF )
        return -1.0;

    // Get either the current time or the stop time
    LARGE_INTEGER qwTime;
    if( m_llStopTime != 0 )
        qwTime.QuadPart = m_llStopTime;
    else
        QueryPerformanceCounter( &qwTime );

    double fTime = qwTime.QuadPart / (double) m_llQPFTicksPerSec;

    return fTime;
}


//--------------------------------------------------------------------------------------
double CDXUTTimer::GetTime()
{
    if( !m_bUsingQPF )
        return -1.0;

    // Get either the current time or the stop time
    LARGE_INTEGER qwTime;
    if( m_llStopTime != 0 )
        qwTime.QuadPart = m_llStopTime;
    else
        QueryPerformanceCounter( &qwTime );

    double fAppTime = (double) ( qwTime.QuadPart - m_llBaseTime ) / (double) m_llQPFTicksPerSec;

    return fAppTime;
}


//--------------------------------------------------------------------------------------
double CDXUTTimer::GetElapsedTime()
{
    if( !m_bUsingQPF )
        return -1.0;

    // Get either the current time or the stop time
    LARGE_INTEGER qwTime;
    if( m_llStopTime != 0 )
        qwTime.QuadPart = m_llStopTime;
    else
        QueryPerformanceCounter( &qwTime );

    double fElapsedTime = (double) ( qwTime.QuadPart - m_llLastElapsedTime ) / (double) m_llQPFTicksPerSec;
    m_llLastElapsedTime = qwTime.QuadPart;

    return fElapsedTime;
}


//--------------------------------------------------------------------------------------
bool CDXUTTimer::IsStopped()
{
    return m_bTimerStopped;
}



//--------------------------------------------------------------------------------------
// Returns the DirectX SDK media path
//       cchDest is the size in WCHARs of strDest.  Be careful not to 
//       pass in sizeof(strDest) on UNICODE builds.
//--------------------------------------------------------------------------------------
HRESULT DXUTGetDXSDKMediaPathCch( WCHAR* strDest, int cchDest )
{
    if( strDest == NULL || cchDest < 1 )
        return E_INVALIDARG;

    lstrcpy( strDest, TEXT("") );

    // Open the appropriate registry key
    HKEY  hKey;
    LONG lResult = RegOpenKeyEx( HKEY_LOCAL_MACHINE,
                                L"Software\\Microsoft\\DirectX SDK",
                                0, KEY_READ, &hKey );
    if( ERROR_SUCCESS != lResult ) 
        return E_FAIL;

    DWORD dwType;
    DWORD dwSize = cchDest * sizeof(WCHAR);
    lResult = RegQueryValueEx( hKey, L"DX9S4SDK Samples Path", NULL,
                              &dwType, (BYTE*)strDest, &dwSize );
    strDest[cchDest-1] = 0; // RegQueryValueEx doesn't NULL term if buffer too small
    RegCloseKey( hKey );

    if( ERROR_SUCCESS != lResult )
        return E_FAIL;

    const WCHAR* strMedia = L"\\Media\\";
    if( lstrlen(strDest) + lstrlen(strMedia) < cchDest )
        wcscat( strDest, strMedia );
    else
        return E_INVALIDARG;

    return S_OK;
}


//--------------------------------------------------------------------------------------
// Tries to find the location of a SDK media file
//       cchDest is the size in WCHARs of strDestPath.  Be careful not to 
//       pass in sizeof(strDest) on UNICODE builds.
//--------------------------------------------------------------------------------------
HRESULT DXUTFindDXSDKMediaFileCch( WCHAR* strDestPath, int cchDest, LPCWSTR strFilename )
{
    bool bFound;
    WCHAR strSearchFor[MAX_PATH];
    
    if( NULL==strFilename || strFilename[0] == 0 || NULL==strDestPath || cchDest < 10 )
        return E_INVALIDARG;

    // Get the DirectX SDK's media dir if the SDK is installed
    WCHAR strMediaDir[MAX_PATH] = {0};
    DXUTGetDXSDKMediaPathCch( strMediaDir, MAX_PATH );

    // Get the exe name, and exe path
    WCHAR strExePath[MAX_PATH] = {0};
    WCHAR strExeName[MAX_PATH] = {0};
    WCHAR* strLastSlash = NULL;
    GetModuleFileName( NULL, strExePath, MAX_PATH );
    strExePath[MAX_PATH-1]=0;
    strLastSlash = wcsrchr( strExePath, TEXT('\\') );
    if( strLastSlash )
    {
        lstrcpyn( strExeName, &strLastSlash[1], MAX_PATH );

        // Chop the exe name from the exe path
        *strLastSlash = 0;

        // Chop the .exe from the exe name
        strLastSlash = wcsrchr( strExeName, TEXT('.') );
        if( strLastSlash )
            *strLastSlash = 0;
    }

    // Typical directories:
    //      .\
    //      ..\
    //      ..\..\
    //      %EXE_DIR%\
    //      %EXE_DIR%\..\
    //      %EXE_DIR%\..\..\
    //      %EXE_DIR%\..\%EXE_NAME%
    //      %EXE_DIR%\..\..\%EXE_NAME%
    //      DXSDK media path

    // Typical directory search
    bFound = DXUTFindMediaSearchTypicalDirs( strDestPath, cchDest, strFilename, strExePath, strExeName, strMediaDir );
    if( bFound )
        return S_OK;

    // Typical directory search again, but also look in a subdir called "\media\" 
    _snwprintf( strSearchFor, MAX_PATH, L"media\\%s", strFilename ); strSearchFor[MAX_PATH-1] = 0;
    bFound = DXUTFindMediaSearchTypicalDirs( strDestPath, cchDest, strSearchFor, strExePath, strExeName, strMediaDir );
    if( bFound )
        return S_OK;

    WCHAR strLeafName[MAX_PATH] = {0};

    // Search all parent directories starting at .\ and using strFilename as the leaf name
    wcsncpy( strLeafName, strFilename, MAX_PATH ); strLeafName[MAX_PATH-1] = 0;
    bFound = DXUTFindMediaSearchParentDirs( strDestPath, cchDest, L".", strLeafName );
    if( bFound )
        return S_OK;

    // Search all parent directories starting at the exe's dir and using strFilename as the leaf name
    bFound = DXUTFindMediaSearchParentDirs( strDestPath, cchDest, strExePath, strLeafName );
    if( bFound )
        return S_OK;

    // Search all parent directories starting at .\ and using "media\strFilename" as the leaf name
    _snwprintf( strLeafName, MAX_PATH, L"media\\%s", strFilename ); strLeafName[MAX_PATH-1] = 0;
    bFound = DXUTFindMediaSearchParentDirs( strDestPath, cchDest, L".", strLeafName );
    if( bFound )
        return S_OK;

    // Search all parent directories starting at the exe's dir and using "media\strFilename" as the leaf name
    bFound = DXUTFindMediaSearchParentDirs( strDestPath, cchDest, strExePath, strLeafName );
    if( bFound )
        return S_OK;

    // On failure, return the file as the path but also return an error code
    wcsncpy( strDestPath, strFilename, cchDest );
    strDestPath[cchDest-1] = 0;

    return DXUTERR_MEDIANOTFOUND;
}


//--------------------------------------------------------------------------------------
// Search a set of typical directories
//--------------------------------------------------------------------------------------
bool DXUTFindMediaSearchTypicalDirs( WCHAR* strSearchPath, int cchSearch, LPCWSTR strLeaf, 
                                     WCHAR* strExePath, WCHAR* strExeName, LPCWSTR strMediaDir )
{
    // Typical directories:
    //      .\
    //      ..\
    //      ..\..\
    //      %EXE_DIR%\
    //      %EXE_DIR%\..\
    //      %EXE_DIR%\..\..\
    //      %EXE_DIR%\..\%EXE_NAME%
    //      %EXE_DIR%\..\..\%EXE_NAME%
    //      DXSDK media path

    // Search in .\  
    wcsncpy( strSearchPath, strLeaf, cchSearch ); strSearchPath[cchSearch-1] = 0;
    if( GetFileAttributes( strSearchPath ) != 0xFFFFFFFF )
        return true;

    // Search in ..\  
    _snwprintf( strSearchPath, cchSearch, L"..\\%s", strLeaf ); strSearchPath[cchSearch-1] = 0;
    if( GetFileAttributes( strSearchPath ) != 0xFFFFFFFF )
        return true;

    // Search in ..\..\ 
    _snwprintf( strSearchPath, cchSearch, L"..\\..\\%s", strLeaf ); strSearchPath[cchSearch-1] = 0;
    if( GetFileAttributes( strSearchPath ) != 0xFFFFFFFF )