!
! Subroutine: LoadGrid
! callback: SelectPoint_Zoom
!
SUBROUTINE LoadGrid
!***************************************************************************
!*																	       *
!*  THIS SUBROUTINE CREATES A DIALOG BOX THAT ALLOWS THE USER TO INPUT THE *
!*  .feg GRID FILE.  THIS ROUTINE USES THE SYSTEM COMMON DIALOG ACCESS     *
!*  THROUGH THE WINDOWS API.                                               *
!*																		   *
!***************************************************************************

  use dflib
  use dfwin
  use Global

  implicit none

  type (t_openfilename) iofn

  logical(4) iRet
  integer(4) ierror
  integer(4) iUnit
  character(26*7) allfilters
  character(60) dlgtitle
  logical(4) checked

! added on March 10, 2005, needs to set to ZoomInOut mode
  external SelectPoint_Zoom

! update statusbar infor.
  call setstatusbar(0,'LoadGrid'C)
  call setstatusbar(1,' 'C)
  
!
  ALLFILTERS = 'Finite Element Grid files (*.feg)' // char(0) // '*.FEG' // char(0) // char(0)


  DLGTITLE = 'Input Grid File'C

  iofn%HWNDOWNER = GETHWNDQQ(QWIN$FRAMEWINDOW)
  iofn%HINSTANCE = NULL
  iofn%LPSTRFILTER = LOC(ALLFILTERS)
  iofn%LPSTRCUSTOMFILTER = NULL
  iofn%NMAXCUSTFILTER = NULL
  iofn%NFILTERINDEX = 1
  iofn%LPSTRFILE = LOC(FEG_INP) 
  iofn%NMAXFILE = LEN(FEG_INP) 
  iofn%LPSTRFILETITLE = NULL 
  iofn%NMAXFILETITLE = NULL
  iofn%LPSTRINITIALDIR = NULL
  iofn%LPSTRTITLE = LOC(DLGTITLE)
  iofn%FLAGS = NULL 
  iofn%NFILEOFFSET = NULL
  iofn%NFILEEXTENSION = NULL
  iofn%LPSTRDEFEXT = NULL
  iofn%LCUSTDATA = NULL
  iofn%LPFNHOOK = NULL
  iofn%LPTEMPLATENAME = NULL 

  !iofn%LSTRUCTSIZE = (BIT_SIZE(iofn%LSTRUCTSIZE) +        &
  !                     BIT_SIZE(iofn%HWNDOWNER) +        &
  !                     BIT_SIZE(iofn%HINSTANCE) +        &
  !                     BIT_SIZE(iofn%LPSTRFILTER) +        &
  !                     BIT_SIZE(iofn%LPSTRCUSTOMFILTER) +        &
  !                     BIT_SIZE(iofn%NMAXCUSTFILTER) +        &
  !                     BIT_SIZE(iofn%NFILTERINDEX) +        &
  !                     BIT_SIZE(iofn%LPSTRFILE) +        &
  !                     BIT_SIZE(iofn%NMAXFILE) +        &
  !                     BIT_SIZE(iofn%LPSTRFILETITLE) +        &
  !                     BIT_SIZE(iofn%NMAXFILETITLE) +        &
  !                     BIT_SIZE(iofn%LPSTRINITIALDIR) +        &
  !                     BIT_SIZE(iofn%LPSTRTITLE) +        &
  !                     BIT_SIZE(iofn%FLAGS) +        &
  !                     BIT_SIZE(iofn%NFILEOFFSET) +        &
  !                     BIT_SIZE(iofn%NFILEEXTENSION) +        &
  !                     BIT_SIZE(iofn%LPSTRDEFEXT) +        &
  !                     BIT_SIZE(iofn%LCUSTDATA) +        &
  !                     BIT_SIZE(iofn%LPFNHOOK) +        &
  !                     BIT_SIZE(iofn%LPTEMPLATENAME))/8      ! 8 bit = 1 Byte
  !N.B. When converting this program to the x64 platform, the above code stopped working;
  !     I found a hint on the web, and replaced it with:
  iofn%LSTRUCTSIZE = SizeOf(iofn)
  
  if (.not.(GridLoaded)) then
     iRet = GETOPENFILENAME(iofn)
     CALL COMDLGER(ierror)
     ! CHECK TO SEE IF THE OK BUTTON HAS BEEN PRESSED
     if(iRet .and. (ierror == 0)) then
	    call Read_Grid
        ! After successful Read_Grid, LOGICAL :: gridLoaded in MODULE Global is set .TRUE.
		if (gridLoaded) then
		  ! adjust window title
          ! enter new frame window title
		  iUnit = getactiveqq()
          iRet = SetWindowText(GetHwndQQ(iUnit), TRIM(feg_inp) // CHAR(0))
		  call DrawGrid
		  if(BaseLoaded) call DrawBase
		  ! Added on March 10, 2005
		  ! set to default zoom in/out with 2.02 scale factor when new grid is loaded
          iUnit = getactiveqq()
		  iRet = REGISTERMOUSEEVENT (iUnit, MOUSE$LBUTTONDOWN, SelectPoint_Zoom)
		  ZoomInOut_checked = .true.
        end if
     endif
  else
     call error3
  end if 
! update statusbar infor.
  call setstatusbar(0, 'Ready'C)
  call setstatusbar(1, ' 'C)
return
end subroutine LoadGrid