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musictool.cpp
资源名称：Visual C++视频音频开发实用工程案例精选.rar　[点击查看]
上传用户：tuheem
上传日期：2007-05-01
资源大小：21889k
文件大小：19k
源码类别：

多媒体编程

开发平台：

Visual C++

musictool.cpp：源码内容
  1. //-----------------------------------------------------------------------------
  2. // 文件名: MusicTool.cpp
  3. //
  4. // 描  述: 使用DirectMusic，播放主片段
  5. //-----------------------------------------------------------------------------
  6. #define STRICT
  7. #include <windows.h>
  8. #include <basetsd.h>
  9. #include <commdlg.h>
  10. #include <commctrl.h>
  11. #include <dmusicc.h>
  12. #include <dmusici.h>
  13. #include <dmusicf.h>
  14. #include <dxerr9.h>
  15. #include <cguid.h>
  16. #include <tchar.h>
  17. #include <stdio.h>
  18. #include "resource.h"
  19. #include "DMUtil.h"
  20. #include "DXUtil.h"
  21. #include "EchoTool.h"
  22. #include "MeasTool.h"
  28. INT_PTR CALLBACK MainDlgProc( HWND hDlg, UINT msg, WPARAM wParam, LPARAM lParam );
  29. HRESULT OnInitDialog( HWND hDlg );
  30. HRESULT ProcessDirectMusicMessages( HWND hDlg );
  31. VOID    OnOpenSoundFile( HWND hDlg );
  32. HRESULT LoadSegmentFile( HWND hDlg, TCHAR* strFileName );
  33. HRESULT OnPlaySegment( HWND hDlg );
  34. VOID    EnablePlayUI( HWND hDlg, BOOL bEnable );
  35. HRESULT OnChangeTool( HWND hDlg );
  40. HINSTANCE               g_hInst                 = NULL;
  41. CMusicManager*          g_pMusicManager         = NULL;
  42. CMusicSegment*          g_pMusicSegment         = NULL;
  43. CEchoTool*              g_pEchoTool             = NULL;
  44. CMeasureTool*           g_pMeasureTool1         = NULL;
  45. CMeasureTool*           g_pMeasureTool2         = NULL;
  46. IDirectMusicTool*       g_pCurrentTool          = NULL;
  47. IDirectMusicGraph*      g_pGraph                = NULL;
  48. HANDLE                  g_hDMusicMessageEvent   = NULL;
  53. //-----------------------------------------------------------------------------
  54. // 函数名: WinMain()
  55. // 描  述: 应用程序的入口。使用简单的对话框与用户交互 
  56. //-----------------------------------------------------------------------------
  57. INT APIENTRY WinMain( HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR pCmdLine, 
  58.                       INT nCmdShow )
  59. {
  60.     HWND    hDlg = NULL;
  61.     BOOL    bDone = FALSE;
  62.     int     nExitCode = 0;
  63.     HRESULT hr; 
  64.     DWORD   dwResult;
  65.     MSG     msg;
  67.     g_hInst = hInst;
  69.     // 显示主对话框。
  70.     hDlg = CreateDialog( hInst, MAKEINTRESOURCE(IDD_MAIN), 
  71.                          NULL, MainDlgProc );
  73.     while( !bDone ) 
  74.     { 
  75.         dwResult = MsgWaitForMultipleObjects( 1, &g_hDMusicMessageEvent, 
  76.                                               FALSE, INFINITE, QS_ALLEVENTS );
  77.         switch( dwResult )
  78.         {
  79.             case WAIT_OBJECT_0 + 0:
  80.                 // 发信号给g_hDPMessageEvent，因此有可用的messages消息。
  81.                 if( FAILED( hr = ProcessDirectMusicMessages( hDlg ) ) ) 
  82.                 {
  83.                     DXTRACE_ERR_MSGBOX( TEXT("ProcessDirectMusicMessages"), hr );
  84.                     return FALSE;
  85.                 }
  86.                 break;
  88.             case WAIT_OBJECT_0 + 1:
  89.                 // Windows消息可用。
  90.                 while( PeekMessage( &msg, NULL, 0, 0, PM_REMOVE ) ) 
  91.                 { 
  92.                     if( !IsDialogMessage( hDlg, &msg ) )  
  93.                     {
  94.                         TranslateMessage( &msg ); 
  95.                         DispatchMessage( &msg ); 
  96.                     }
  98.                     if( msg.message == WM_QUIT )
  99.                     {
  100.                         nExitCode = (int)msg.wParam;
  101.                         bDone     = TRUE;
  102.                         DestroyWindow( hDlg );
  103.                     }
  104.                 }
  105.                 break;
  106.         }
  107.     }
  109.     return nExitCode;
  110. }
  113. //-----------------------------------------------------------------------------
  114. // 函数名: MainDlgProc()
  115. // 描  述: 处理对话框消息
  116. //-----------------------------------------------------------------------------
  117. INT_PTR CALLBACK MainDlgProc( HWND hDlg, UINT msg, WPARAM wParam, LPARAM lParam )
  118. {
  119.     HRESULT hr;
  121.     switch( msg ) 
  122.     {
  123.         case WM_INITDIALOG:
  124.             if( FAILED( hr = OnInitDialog( hDlg ) ) )
  125.             {
  126.                 DXTRACE_ERR_MSGBOX( TEXT("OnInitDialog"), hr );
  127.                 MessageBox( hDlg, "Error initializing DirectMusic.  Sample will now exit.", 
  128.                                   "DirectMusic Sample", MB_OK | MB_ICONERROR );
  129.                 PostQuitMessage( IDABORT );
  130.                 return FALSE;
  131.             }
  133.             break;
  135.         case WM_COMMAND:
  136.             switch( LOWORD(wParam) )
  137.             {
  138.                 case IDC_SOUNDFILE:
  139.                     OnOpenSoundFile( hDlg );
  140.                     break;
  142.                 case IDCANCEL:
  143.                     PostQuitMessage( IDCANCEL );
  144.                     break;
  146.                 case IDC_PLAY:
  147.                     if( FAILED( hr = OnPlaySegment( hDlg ) ) )
  148.                     {
  149.                         DXTRACE_ERR_MSGBOX( TEXT("OnPlaySegment"), hr );
  150.                         MessageBox( hDlg, "Error playing DirectMusic segment. "
  151.                                     "Sample will now exit.", "DirectMusic Sample", 
  152.                                     MB_OK | MB_ICONERROR );
  153.                         PostQuitMessage( IDABORT );
  154.                     }
  155.                     break;
  157.                 case IDC_STOP:
  158.                     // 播放片段时，简单调用Stop()不会停止任何MIDI sustain pedals, 
  159. // 但调用StopAll()可以。
  160.                     if( g_pMusicManager )
  161.                         g_pMusicManager->StopAll(); 
  162.                     EnablePlayUI( hDlg, TRUE );
  163.                     break;
  165.                 case IDC_TOOL_COMBO:
  166.                     OnChangeTool( hDlg );
  167.                     break;
  169.                 case IDHELP:
  170.                     DXUtil_LaunchReadme( hDlg );
  171.                     break;
  173.                 default:
  174. // 不处理消息
  175.                     return FALSE; 
  176.             }
  177.             break;
  179.         case WM_DESTROY:
  180.             // 清除一切
  181.             SAFE_RELEASE( g_pGraph );
  182.             SAFE_DELETE( g_pMusicSegment );
  183.             SAFE_DELETE( g_pMusicManager );
  184.             SAFE_DELETE( g_pEchoTool );
  185.             SAFE_DELETE( g_pMeasureTool1 );
  186.             SAFE_DELETE( g_pMeasureTool2 );
  187.             CloseHandle( g_hDMusicMessageEvent );
  188.             break; 
  190.         default:
  191. // 不处理消息
  192.             return FALSE; 
  193.     }
  195.     return TRUE; 
  196. }
  201. //-----------------------------------------------------------------------------
  202. // 函数名: OnInitDialog()
  203. // 描  述: 初始化对话框(建立UI控制等)
  204. //-----------------------------------------------------------------------------
  205. HRESULT OnInitDialog( HWND hDlg )
  206. {
  207.     HRESULT hr;
  208.     LONG lIndex;
  210.     // 为对话框设置icon
  211.     HICON hIcon = LoadIcon( g_hInst, MAKEINTRESOURCE( IDR_MAINFRAME ) );
  212.     SendMessage( hDlg, WM_SETICON, ICON_BIG,   (LPARAM) hIcon );  // 设置大icon
  213.     SendMessage( hDlg, WM_SETICON, ICON_SMALL, (LPARAM) hIcon );  // 设置小icon
  215.     g_hDMusicMessageEvent = CreateEvent( NULL, FALSE, FALSE, NULL );
  216.     g_pMusicManager = new CMusicManager();
  217.     if( NULL == g_pMusicManager )
  218.         return E_OUTOFMEMORY;
  220.     // 使用缺省音轨初始化DirectMusic
  221.     hr = g_pMusicManager->Initialize( hDlg );
  222.     if( FAILED(hr) )
  223.         return DXTRACE_ERR_MSGBOX( TEXT("Initialize"), hr );
  224.     
  225.     IDirectMusicPerformance8* pPerformance    = g_pMusicManager->GetPerformance();
  226.     IDirectMusicAudioPath8* pDefaultAudioPath = g_pMusicManager->GetDefaultAudioPath();
  228.     // 产生一个DirectMusicGraph,并告知相关的参数
  229.     hr = pDefaultAudioPath->GetObjectInPath( 0, DMUS_PATH_PERFORMANCE_GRAPH, 0,
  230.                                              GUID_NULL, 0, IID_IDirectMusicGraph, 
  231.                                              (LPVOID*) &g_pGraph );
  233.     SAFE_RELEASE( pDefaultAudioPath );
  235.     if( FAILED( hr ) )
  236.         return DXTRACE_ERR_MSGBOX( TEXT("GetObjectInPath"), hr );
  238.     // 注册片段通知
  239.     if( FAILED( hr = pPerformance->AddNotificationType( GUID_NOTIFICATION_SEGMENT ) ) )
  240.         return DXTRACE_ERR_MSGBOX( TEXT("AddNotificationType"), hr );
  242.     if( FAILED( hr = pPerformance->AddNotificationType( GUID_NOTIFICATION_MEASUREANDBEAT) ) )
  243.         return DXTRACE_ERR_MSGBOX( TEXT("AddNotificationType"), hr );
  245.     if( FAILED( hr = pPerformance->SetNotificationHandle( g_hDMusicMessageEvent, 0 ) ) )
  246.         return DXTRACE_ERR_MSGBOX( TEXT("SetNotificationHandle"), hr );
  248.     g_pEchoTool = new CEchoTool();
  249.     if( NULL == g_pEchoTool )
  250.         return E_OUTOFMEMORY;
  251.     g_pMeasureTool1 = new CMeasureTool(hDlg);
  252.     if( NULL == g_pMeasureTool1 )
  253.         return E_OUTOFMEMORY;
  254.     g_pMeasureTool2 = new CMeasureTool(hDlg);
  255.     if( NULL == g_pMeasureTool2 )
  256.         return E_OUTOFMEMORY;
  258.     // 初始化UI
  259.     HWND hToolCombo = GetDlgItem( hDlg, IDC_TOOL_COMBO );
  260.     lIndex = (LONG)SendMessage( hToolCombo, CB_ADDSTRING, 0, (LPARAM) TEXT("无") );
  261.     SendMessage( hToolCombo, CB_SETITEMDATA, lIndex, (LPARAM) NULL );
  262.     lIndex = (LONG)SendMessage( hToolCombo, CB_ADDSTRING, 0, (LPARAM) TEXT("Echo工具") );
  263.     SendMessage( hToolCombo, CB_SETITEMDATA, lIndex, (LPARAM) (IDirectMusicTool*) g_pEchoTool );
  264.     lIndex = (LONG)SendMessage( hToolCombo, CB_ADDSTRING, 0, (LPARAM) TEXT("Measure工具") );
  265.     SendMessage( hToolCombo, CB_SETITEMDATA, lIndex, (LPARAM) (IDirectMusicTool*) g_pMeasureTool1 );
  266.     SendMessage( hToolCombo, CB_SETCURSEL, 0, 0 );
  268.     // 装载缺省的音频片段 
  269.     TCHAR strFileName[MAX_PATH+1];
  270.     DXUtil_GetDXSDKMediaPathCb( strFileName, sizeof(strFileName) );
  271.     strcat( strFileName, "sample.sgt" );
  272.     if( S_FALSE == LoadSegmentFile( hDlg, strFileName ) )
  273.     {
  274.         // 设置UI控制
  275.         SetDlgItemText( hDlg, IDC_FILENAME, TEXT("No file loaded.") );
  276.     }
  277.     else
  278.     {
  279.         IDirectMusicSegment8*   pPrimarySegment8;
  280.         DMUS_TEMPO_PARAM        tempo;
  281.         MUSIC_TIME              mtTime = 0;
  283.         pPrimarySegment8 = g_pMusicSegment->GetSegment();
  285.         tempo.mtTime = 0;
  286.         tempo.dblTempo = 70.;
  287.         pPrimarySegment8->SetParam(GUID_TempoParam, 0xffffffff, DMUS_SEG_ALLTRACKS, mtTime, &tempo);
  288.     }
  291.     return S_OK;
  292. }
  297. //-----------------------------------------------------------------------------
  298. // 函数名: OnOpenSoundFile()
  299. // 描  述: 当用户需要打开一个声音文件时，调用
  300. //-----------------------------------------------------------------------------
  301. VOID OnOpenSoundFile( HWND hDlg ) 
  302. {
  303.     static TCHAR strFileName[MAX_PATH+1] = TEXT("");
  304.     static TCHAR strPath[MAX_PATH+1] = TEXT("");
  306.     // 得到缺省的多媒体路径(如C:MSSDKSAMPLESDMUSICMEDIA)
  307.     if( '' == strPath[0] )
  308.     {
  309.         DXUtil_GetDXSDKMediaPathCb( strPath, sizeof(strPath) );
  310.     }
  312.     // 建立OPENFILENAME结构
  313.     OPENFILENAME ofn = { sizeof(OPENFILENAME), hDlg, NULL,
  314.                          TEXT("DirectMusic Content Files*.sgt;*.mid;*.rmiAll Files*.*"), NULL,
  315.                          0, 1, strFileName, MAX_PATH, NULL, 0, strPath,
  316.                          TEXT("Open Content File"),
  317.                          OFN_FILEMUSTEXIST|OFN_HIDEREADONLY, 0, 0,
  318.                          TEXT(".sgt"), 0, NULL, NULL };
  320.     // 播放片段时，简单调用Stop()不会停止任何MIDI sustain pedals, 
  321. // 但调用StopAll()可以。
  322.     if( g_pMusicManager )
  323.         g_pMusicManager->StopAll(); 
  325.     // 为播放装载的文件更新UI控制
  326.     EnableWindow(  GetDlgItem( hDlg, IDC_PLAY ), FALSE);
  327.     EnableWindow(  GetDlgItem( hDlg, IDC_STOP ), FALSE);
  328.     SetDlgItemText( hDlg, IDC_FILENAME, TEXT("Loading file...") );
  330.     // 显示OpenFileName对话框。然后尝试装载指定的文件
  331.     if( TRUE != GetOpenFileName( &ofn ) )
  332.     {
  333.         SetDlgItemText( hDlg, IDC_FILENAME, TEXT("Load aborted.") );
  334.         return;
  335.     }
  337.     if( S_FALSE == LoadSegmentFile( hDlg, strFileName ) )
  338.     {
  339.         // 不是一个关键的错误，因此仅仅更新状态
  340.         SetDlgItemText( hDlg, IDC_FILENAME, TEXT("Could not create segment from file.") );
  341.     }
  343.     // 记忆路径
  344.     strcpy( strPath, strFileName );
  345.     char* strLastSlash = strrchr( strPath, '\' );
  346.     if( strLastSlash )
  347.         strLastSlash[0] = '';
  348. }
  353. //-----------------------------------------------------------------------------
  354. // 函数名: LoadSegmentFile()
  355. // 描  述: 装载片段文件
  356. //-----------------------------------------------------------------------------
  357. HRESULT LoadSegmentFile( HWND hDlg, TCHAR* strFileName )
  358. {
  359.     HRESULT hr;
  361.     SetDlgItemText( hDlg, IDC_FILENAME, TEXT("") );
  363.     // 释放先前的片段，建立一个新的
  364.     SAFE_DELETE( g_pMusicSegment );
  366.     // 因为老的剧本已释放，有装载器收集垃圾
  367.     g_pMusicManager->CollectGarbage();
  369.     // 为搜索与该文件相关的DirectMusic内容而设置的基于文件名的多媒体路径(如C:MEDIA)
  370.     TCHAR strMediaPath[MAX_PATH+1];
  371.     _tcsncpy( strMediaPath, strFileName, MAX_PATH );
  372.     strMediaPath[MAX_PATH-1] = 0;
  373.     TCHAR* strLastSlash = _tcsrchr(strMediaPath, TEXT('\'));
  374.     if( strLastSlash )
  375.     {
  376.         *strLastSlash = 0;
  377.         if( FAILED( hr = g_pMusicManager->SetSearchDirectory( strMediaPath ) ) )
  378.             return DXTRACE_ERR_MSGBOX( TEXT("SetSearchDirectory"), hr );
  379.     }
  380.     
  381.     // 为装载正确的乐器，DirectMusic必须知道该文件是否是一个标准的MIDI文件
  382.     BOOL bMidiFile = FALSE;
  383.     if( strstr( strFileName, ".mid" ) != NULL ||
  384.         strstr( strFileName, ".rmi" ) != NULL ) 
  385.     {
  386.         bMidiFile = TRUE;
  387.     }
  389.     // 将文件载入一个DirectMusic片段中 
  390.     if( FAILED( g_pMusicManager->CreateSegmentFromFile( &g_pMusicSegment, strFileName, 
  391.                                                         TRUE, bMidiFile ) ) )
  392.     {
  393.         // 不是一个关键的错误，因此仅仅更新状态
  394.         return S_FALSE; 
  395.     }
  397.     // 为显示片段被装载，更新UI控制
  398.     SetDlgItemText( hDlg, IDC_FILENAME, strFileName );
  399.     EnablePlayUI( hDlg, TRUE );
  401.     return S_OK;
  402. }
  407. //-----------------------------------------------------------------------------
  408. // 函数名: ProcessDirectMusicMessages()
  409. // 描  述: 处理DirectMusic音符消息
  410. //-----------------------------------------------------------------------------
  411. HRESULT ProcessDirectMusicMessages( HWND hDlg )
  412. {
  413.     HRESULT hr;
  414.     IDirectMusicPerformance8* pPerf = NULL;
  415.     DMUS_NOTIFICATION_PMSG* pPMsg;
  416.         
  417.     if( NULL == g_pMusicManager )
  418.         return S_OK;
  420.     pPerf = g_pMusicManager->GetPerformance();
  422.     // Get waiting notification message from the performance
  423.     while( S_OK == pPerf->GetNotificationPMsg( &pPMsg ) )
  424.     {
  425.         switch( pPMsg->dwNotificationOption )
  426.         {
  427.         case DMUS_NOTIFICATION_SEGEND:
  428.             if( pPMsg->punkUser )
  429.             {
  430.                 IDirectMusicSegmentState8* pSegmentState   = NULL;
  431.                 IDirectMusicSegment*       pNotifySegment   = NULL;
  432.                 IDirectMusicSegment8*      pNotifySegment8  = NULL;
  433.                 IDirectMusicSegment8*      pPrimarySegment8 = NULL;
  435.                 // pPMsg->punkUser包括一个IDirectMusicSegmentState8, 
  436.                 // 从而我们能够查询SegmentState引用的片段
  437.                 if( FAILED( hr = pPMsg->punkUser->QueryInterface( IID_IDirectMusicSegmentState8,
  438.                                                                   (VOID**) &pSegmentState ) ) )
  439.                     return DXTRACE_ERR_MSGBOX( TEXT("QueryInterface"), hr );
  441.                 if( SUCCEEDED( hr = pSegmentState->GetSegment( &pNotifySegment ) ) )
  442.                 {
  443.                     if( FAILED( hr = pNotifySegment->QueryInterface( IID_IDirectMusicSegment8,
  444.                                                                      (VOID**) &pNotifySegment8 ) ) )
  445.                         return DXTRACE_ERR_MSGBOX( TEXT("QueryInterface"), hr );
  447.                     // 为主要的片段得到IDirectMusicSegment
  448.                     pPrimarySegment8 = g_pMusicSegment->GetSegment();
  450.                     // 推断这是什么片段
  451.                     if( pNotifySegment8 == pPrimarySegment8 )
  452.                     {
  453.                         // 为显示停止音频，更新UI控制
  454.                         EnablePlayUI( hDlg, TRUE );
  455.                     }
  456.                 }
  458.                 // 清除
  459.                 SAFE_RELEASE( pSegmentState );
  460.                 SAFE_RELEASE( pNotifySegment );
  461.                 SAFE_RELEASE( pNotifySegment8 );
  462.             }
  463.             break;
  464.         }
  466.         pPerf->FreePMsg( (DMUS_PMSG*)pPMsg ); 
  467.     }
  469.     return S_OK;
  470. }
  474. //-----------------------------------------------------------------------------
  475. // 函数名: OnPlaySegment()
  476. // 描  述: 播放片段
  477. //-----------------------------------------------------------------------------
  478. HRESULT OnPlaySegment( HWND hDlg )
  479. {
  480.     HRESULT hr;
  482.     HWND hLoopButton = GetDlgItem( hDlg, IDC_LOOP_CHECK );
  483.     BOOL bLooped = ( SendMessage( hLoopButton, BM_GETSTATE, 0, 0 ) == BST_CHECKED );
  485.     if( bLooped )
  486.     {
  487.         // 设置片段的重复次数
  488.         if( FAILED( hr = g_pMusicSegment->SetRepeats( DMUS_SEG_REPEAT_INFINITE ) ) )
  489.             return DXTRACE_ERR_MSGBOX( TEXT("SetRepeats"), hr );
  490.     }
  491.     else
  492.     {
  493.         // 设置片段不重复
  494.         if( FAILED( hr = g_pMusicSegment->SetRepeats( 0 ) ) )
  495.             return DXTRACE_ERR_MSGBOX( TEXT("SetRepeats"), hr );
  496.     }
  498.     // 播放片段和等待. 当当前有一个片段在播放时，DMUS_SEGF_BEAT表示在下一次敲打时播放
  499.     if( FAILED( hr = g_pMusicSegment->Play( DMUS_SEGF_BEAT ) ) )
  500.         return DXTRACE_ERR_MSGBOX( TEXT("Play"), hr );
  502.     EnablePlayUI( hDlg, FALSE );
  504.     return S_OK;
  505. }
  510. //-----------------------------------------------------------------------------
  511. // 函数名: EnablePlayUI( )
  512. // 描  述: 是否允许UI控制的表演 
  513. //-----------------------------------------------------------------------------
  514. VOID EnablePlayUI( HWND hDlg, BOOL bEnable )
  515. {
  516.     if( bEnable )
  517.     {
  518.         EnableWindow(   GetDlgItem( hDlg, IDC_LOOP_CHECK ), TRUE );
  519.         EnableWindow(   GetDlgItem( hDlg, IDC_STOP ),       FALSE );
  521.         EnableWindow(   GetDlgItem( hDlg, IDC_PLAY ),       TRUE );
  522.         SetFocus(       GetDlgItem( hDlg, IDC_PLAY ) );
  523.     }
  524.     else
  525.     {
  526.         EnableWindow(  GetDlgItem( hDlg, IDC_LOOP_CHECK ), FALSE );
  527.         EnableWindow(  GetDlgItem( hDlg, IDC_STOP ),       TRUE );
  528.         SetFocus(      GetDlgItem( hDlg, IDC_STOP ) );
  529.         EnableWindow(  GetDlgItem( hDlg, IDC_PLAY ),       FALSE );
  530.     }
  531. }
  533. //-----------------------------------------------------------------------------
  534. // 函数名: OnChangeTool()
  535. // 描  述: 改变工具
  536. //-----------------------------------------------------------------------------
  537. HRESULT OnChangeTool( HWND hDlg )
  538. {
  539.     HRESULT hr;
  540.     IDirectMusicTool* pSelectedTool;
  541.     LONG lCurSelection;
  543.     lCurSelection = (LONG)SendDlgItemMessage( hDlg, IDC_TOOL_COMBO, CB_GETCURSEL, 0, 0 );
  544.     pSelectedTool = (IDirectMusicTool*) SendDlgItemMessage( hDlg, IDC_TOOL_COMBO, 
  545.                                                             CB_GETITEMDATA, lCurSelection, 0 );
  546.     if( pSelectedTool != g_pCurrentTool )
  547.     {
  548.         // 从当前的表中移除当前的工具
  549.         if( g_pCurrentTool != NULL )
  550.         {
  551.             if( FAILED( hr = g_pGraph->RemoveTool( g_pCurrentTool ) ) )
  552.                 return DXTRACE_ERR_MSGBOX( TEXT("RemoveTool"), hr );
  553.         }
  555.         // 对所有的通道或初始化表时，增加工具到表中 
  556.         if( pSelectedTool != NULL )
  557.         {
  558.             if( FAILED( hr = g_pGraph->InsertTool( pSelectedTool, NULL, 0, 0 ) ) )
  559.                 return DXTRACE_ERR_MSGBOX( TEXT("InsertTool"), hr );
  560.         }
  562.         g_pCurrentTool = pSelectedTool;
  563.     }
  565.     return S_OK;
  566. }