学步园

前面介绍了怎么样显示人物角色，包括名称等等。那么人物角色是怎么样在里面行走的呢？第二人生是通过方向键来控制人物角色的走动，也就是说它是通过接收键盘的消息后不断地计算新的位置来实现移动。下面就是第二人生的消息处理函数代码：

#001 bool LLAppViewer::mainLoop()

#002 {

#003      //-------------------------------------------

#004      // Run main loop until time to quit

#005      //-------------------------------------------

#006 

#007      // Create IO Pump to use for HTTP Requests.

#008      gServicePump = new LLPumpIO(gAPRPoolp);

#009      LLHTTPClient::setPump(*gServicePump);

#010      LLCurl::setCAFile(gDirUtilp->getCAFile());

#011     

#012      // initialize voice stuff here

#013      gLocalSpeakerMgr = new LLLocalSpeakerMgr();

#014      gActiveChannelSpeakerMgr = new LLActiveSpeakerMgr();

#015 

#016      LLVoiceChannel::initClass();

#017      LLVoiceClient::init(gServicePump);

#018                          

#019      LLMemType mt1(LLMemType::MTYPE_MAIN);

#020      LLTimer frameTimer,idleTimer;

#021      LLTimer debugTime;

#022     

#023      // Handle messages

#024      while (!LLApp::isExiting())

#025      {

#026             LLFastTimer::reset(); // Should be outside of any timer instances

#027             {

#028                    LLFastTimer t(LLFastTimer::FTM_FRAME);

#029 

#030                    {

#031                           LLFastTimer t2(LLFastTimer::FTM_MESSAGES);

#032                    #if LL_WINDOWS

#033                           if (!LLWinDebug::setupExceptionHandler())

#034                           {

#035                                  llwarns << " Someone took over my exception handler (post messagehandling)!" << llendl;

#036                           }

#037                    #endif

#038 

#039                           gViewerWindow->mWindow->gatherInput();

#040                    }

#041 

#042 #if 1 && !RELEASE_FOR_DOWNLOAD

#043                    // once per second debug info

#044                    if (debugTime.getElapsedTimeF32() > 1.f)

#045                    {

#046                           debugTime.reset();

#047                    }

#048 #endif

#049 

#050                    if (!LLApp::isExiting())

#051                    {

#052                           // Scan keyboard for movement keys. Command keys and typing

#053                           // are handled by windows callbacks. Don't do this until we're

#054                           // done initializing. JC

#055                           if (gViewerWindow->mWindow->getVisible()

#056                                  && gViewerWindow->getActive()

#057                                  && !gViewerWindow->mWindow->getMinimized()

#058                                  && LLStartUp::getStartupState() == STATE_STARTED

#059                                  && !gViewerWindow->getShowProgress()

#060                                  && !gFocusMgr.focusLocked())

#061                           {

#063                                  LLViewerJoystick::scanJoystick();

#064                           }

#065 

……

#193 

#194      // Save snapshot for next time, if we made it through initialization

#195      if (STATE_STARTED == LLStartUp::getStartupState())

#196      {

#197             saveFinalSnapshot();

#198      }

#199     

#200      delete gServicePump;

#201 

#202      llinfos << "Exiting main_loop" << llendflush;

#203 

#204      return true;

#205 }

 

这里通过调用函数gKeyboard->scanKeyboard()来处理键盘消息的，它实现每个键盘的消息处理，然后调用文件llviewerkeyboard.cpp的函数bind_keyboard_functions()绑定的函数来处理每个事件。比如向前走，就进行如下操作：

gViewerKeyboard.bindNamedFunction("move_forward", camera_move_forward);

当按下向前的按键时，就会调用函数camera_move_forward来处理这个事件，这样就可以调整摄像像的位置，就实现了人物的行走。