Alt tab issues and Game System Requirement

case WM_ACTIVATEAPP:

         if ((bool) wParam)

         {

            Video::reactivate();

            ShowCursor(false);

            if ( Video::isFullScreen() )

               hideTheTaskbar();

 

            // HACK:  Windows 98 (after switching from fullscreen to windowed mode)

            SetForegroundWindow( winState.appWindow );

 

            // If our keyboard state is dirty, clear it

            if( sgKeyboardStateDirty == true )

            {

               sgKeyboardStateDirty = false;

               InitInput();

            }

 

            // Your code may not need this... it was simply a way to inform the script that we were restarting audio!

            Con::executef( 2, "playBGM", 0 );

         }

         else

         {

            // Window lost focus so set a dirty flag on the keyboard state

            if ( lParam == 0 )

               sgKeyboardStateDirty = true;

 

            Video::deactivate();

            restoreTheTaskbar();

 

            alxStopAll();

 

         }

         break;

Yeah, so I totally fixed this. The problem turned out to be a fundamental flaw in the way torque processes WM_ACTIVATEAPP messages. Torque destroys and recreates the window when processing this message, while still in the message loop, which could easily cause the Win32 API to freak out. The solution is to move the actual work of reactivating the game into the next trip through Platform::process, outside the messaging loop.

Part 1: Setting up some extra Video tracking state

In platformVideo.h, after


   static bool smCritical;



insert


   static bool smActive;
   static bool smActivating;
   static bool smReactivating;
   static bool smInactive;



after


   static void setVideo(const char * gapi, const char * vendor, const char * renderer, const char * platform, const char * os, const char * arch);



insert


   static bool isActive() { return smActive; }
   static bool isActivating() { return smActivating; }
   static bool isReactivating() { return smReactivating; }
   static bool isInactive() { return smInactive; }



In platformVideo.cc, after


bool					Video::smCritical = false;
bool					Video::smNeedResurrect = false;



insert


bool                    Video::smActive = false;
bool                    Video::smActivating = false;
bool                    Video::smReactivating = false;
bool                    Video::smInactive = false;



In Video::setDevice, after


      Con::printf( "Activating the %s display device...", renderName );
      smCurrentDevice = smDeviceList[deviceIndex];

      smCritical = true;



insert


	  smActivating = true;



and after


      bool result = smCurrentDevice->activate( width, height, bpp, fullScreen );



insert


	  smActivating = false;
	  smActive = true;
	  smInactive = false;



In Video::deactivate, after


      Platform::minimizeWindow();
      smCritical = false;
   }



insert


   smInactive = true;
   smActive = false;



in Video::reactivate, after


	   Resolution res = DisplayDevice::getResolution();

      smCritical = true;



insert


	  smReactivating = true;



and after


      smCurrentDevice->activate(res.w,res.h,res.bpp,DisplayDevice::isFullScreen());



insert


	  smReactivating = false;
	  smInactive = false;
	  smActive = true;



Ok, now for Part Deux, rearranging the reactivation code in winWindow.cc:

After:


static bool gWindowCreated = false;

static bool windowNotActive = false;



Insert:


static bool gDoReactivate = false;



In Platform::process, after:


void Platform::process()
{



Insert:


   if(gDoReactivate)
   {
            Video::reactivate();
            ShowCursor(false);
            if ( Video::isFullScreen() )
               hideTheTaskbar();

            // HACK:  Windows 98 (after switching from fullscreen to windowed mode)
            SetForegroundWindow( winState.appWindow );

            // If our keyboard state is dirty, clear it
            if( sgKeyboardStateDirty == true )
            {
               sgKeyboardStateDirty = false;
               InitInput();
            }

			gDoReactivate = false;
   }



In WindowProc, after


      case WM_ACTIVATEAPP:
         if ((bool) wParam)
         {



REPLACE THE CODE UP TO THE CLOSURE OF THE IF STATEMENT WITH:


			 if(Video::isInactive() && !Video::isReactivating())
			 {
				gDoReactivate = true;
			 }



So it should look like...


      case WM_ACTIVATEAPP:
         if ((bool) wParam)
         {
			 //>NEW CODE
			 if(Video::isInactive() && !Video::isReactivating())
			 {
				gDoReactivate = true;
			 }
			 //<NEW CODE
         }



NOTE: THIS IS A TENTATIVE FIX, it has not been tested on any other platforms except my own machine, but it no longer crashes when you alt-tab back into the game while it is in fullscreen. I'm actually a little suprised that GG didn't catch this in their QA process, as it seems to be a hardware independant bug in the windows platform code.