rotate.cpp

一个控制WinCE屏幕旋转的小程序,每运行一次旋转90度角.

/********************************************************************** 
THIS   CODE   AND   INFORMATION   IS   PROVIDED   "AS   IS"   WITHOUT   WARRANTY   OF 
ANY   KIND,   EITHER   EXPRESSED   OR   IMPLIED,   INCLUDING   BUT   NOT   LIMITED   TO 
THE   IMPLIED   WARRANTIES   OF   MERCHANTABILITY   AND/OR   FITNESS   FOR   A 
PARTICULAR   PURPOSE. 

Copyright   (c)   1999   Microsoft   Corporation.   All   Rights   Reserved. 

MODULE:   
    rotation.cpp 

ABSTRACT:   
    This   application   code   demonstrates   the   how   you   can   set   up   the   DEVMODE   structure   and   use   the   ChangeDisplaySettingsEx   function   to   rotate   the   screen.   
    Each   time   you   run   the   executable   for   this   code,   the   screen   will   rotate   clockwise   by   90   degrees. 

**********************************************************************/ 

#include   <windows.h > 

int 
WINAPI 
WinMain( 
      HINSTANCE, 
      HINSTANCE, 
#ifdef   UNDER_CE 
      LPWSTR, 
#else 
      LPSTR, 
#endif 
      int 
      ) 
{ 
      DEVMODE   DevMode; 

      int   RotationAngles; 
      int   CurrentAngle; 
      int   NewAngle; 

      // 
      //   Check   for   rotation   support   by   getting   the   rotation   angles   supported. 
      // 

      memset   (&DevMode,   0,   sizeof   (DevMode)); 
      DevMode.dmSize       =   sizeof   (DevMode); 
      DevMode.dmFields   =   DM_DISPLAYQUERYORIENTATION; 

      if   (DISP_CHANGE_SUCCESSFUL   ==   ChangeDisplaySettingsEx(NULL,   &DevMode,   NULL,   CDS_TEST,   NULL)) 
      { 
            RotationAngles   =   DevMode.dmDisplayOrientation; 
            RETAILMSG(1,   (L"ChangeDisplaySettingsEx   supports   these   rotation   angles   %d",   RotationAngles)); 
      } 
      else 
      { 
            RETAILMSG(1,   (L"ChangeDisplaySettingsEx   failed   to   get   the   supported   rotation   angles.")); 
            RotationAngles   =   -1; 
      } 

      // 
      //   Get   the   current   rotation   angle. 
      // 

      memset(&DevMode,   0,   sizeof   (DevMode)); 
      DevMode.dmSize       =   sizeof   (DevMode); 
      DevMode.dmFields   =   DM_DISPLAYORIENTATION; 

      if   (DISP_CHANGE_SUCCESSFUL   ==   ChangeDisplaySettingsEx(NULL,   &DevMode,   NULL,   CDS_TEST,   NULL)) 
      { 
            CurrentAngle   =   DevMode.dmDisplayOrientation; 
            RETAILMSG(1,   (L"ChangeDisplaySettingsEx   reports   the   current   rotation   as   %d",   CurrentAngle)); 
      } 
      else 
      {   
            RETAILMSG(1,   (L"ChangeDisplaySettingsEx   failed   to   get   the   current   rotation   angle.")); 
            CurrentAngle   =   -1; 
      } 

      // 
      //   Rotate   to   the   "next"   angle. 
      // 

      if   (CurrentAngle   >=   0   &&   RotationAngles   >=   0) 
      { 
            NewAngle   =   CurrentAngle; 

            do 
            { 
                  NewAngle   <<=   1; 

                  if   (NewAngle   ==   DMDO_0) 
                  { 
                        NewAngle   =   DMDO_90; 
                  } 

                  if   (NewAngle   >   DMDO_270)
                  { 
                        NewAngle   =   DMDO_0; 
                  } 
            }   while   (!(NewAngle   &   RotationAngles)   &&   (NewAngle   !=   DMDO_0)); 

            memset(&DevMode,   0,   sizeof   (DevMode)); 
            DevMode.dmSize                               =   sizeof   (DevMode); 
            DevMode.dmFields                           =   DM_DISPLAYORIENTATION; 
            DevMode.dmDisplayOrientation   =   NewAngle; 

            if   (DISP_CHANGE_SUCCESSFUL   ==   ChangeDisplaySettingsEx(NULL,   &DevMode,   NULL,   CDS_RESET,   NULL)) 
            { 
                  RETAILMSG(1,   (L"ChangeDisplaySettingsEx   changed   rotation   angle   to   %d",   NewAngle)); 
            } 
            else 
            { 
                  RETAILMSG(1,   (L"ChangeDisplaySettingsEx   failed   to   change   the   rotation   angle   to   %d",   NewAngle)); 
            } 
      } 

      return   0; 
}