AutoHotkey Community

#NoEnv
#SingleInstance, Force
SetBatchLines, -1
SetKeyDelay, 0
SetWinDelay, 0
OnExit, CleanExit



;   settings

Expose_MaxWin := 20   ;   maximum number of windows to handle
Expose_Border := 8      ;   border between thumbs



;   GUI init

Gui, +AlwaysOnTop -Caption  +Toolwindow +Owner +LastFound
Gui, Show, Hide w%A_ScreenWidth% h%A_ScreenHeight% x0 y0 , »Expose«
WinGet, Expose_ID , ID



;   hotkeys

Hotkey, MButton , Expose_Show ,AboveNormal
Hotkey, IfWinActive, ahk_id %Expose_ID%
Hotkey, LButton, Expose_Hide



;   global variables

   Loop, %Expose_MaxWin%
      Expose_WIN%A_Index% := true

   hdc_frontbuffer      := GetDC( Expose_ID )

   hdc_printwindow   := CreateCompatibleDC( hdc_frontbuffer )
   hbm_printwindow   := CreateCompatibleBitmap( hdc_frontbuffer, A_ScreenWidth, A_ScreenHeight )
   hbm_old            := SelectObject( hdc_printwindow, hbm_printwindow)

   hdc_thumbnails      := CreateCompatibleDC( hdc_frontbuffer )
   hbm_thumbnails   := CreateCompatibleBitmap( hdc_frontbuffer, A_ScreenWidth, A_ScreenHeight )
   hbm_old            := SelectObject( hdc_thumbnails, hbm_thumbnails )

   hdc_backbuffer      := CreateCompatibleDC( hdc_frontbuffer )
   hbm_backbuffer      := CreateCompatibleBitmap( hdc_frontbuffer, A_ScreenWidth, A_ScreenHeight )
   hbm_old            := SelectObject( hdc_backbuffer, hbm_backbuffer)

   hdc_desktop         := CreateCompatibleDC( hdc_frontbuffer )
   hbm_desktop         := CreateCompatibleBitmap( hdc_frontbuffer, A_ScreenWidth, A_ScreenHeight )
   hbm_old            := SelectObject( hdc_desktop, hbm_desktop )

; other global variables:
;
;     Expose_ID
;     Expose_Cols
;     Expose_Rows
;     Expose_WIN0
;     Expose_Border
;     win_id
;     x
;     y

Return





CleanExit:

   Gui, Destroy
   ReleaseDC( Expose_ID, hdc_frontbuffer )
   ReleaseDC( Expose_ID, hdc_copy )
   DeleteObject( hbm_printwindow )
   DeleteDC( hdc_printwindow )
   DeleteObject( hbm_window )
   DeleteDC( hdc_window )
   DeleteObject( hbm_backbuffer )
   DeleteDC( hdc_backbuffer )
   DeleteObject( hbm_desktop )
   DeleteDC( hdc_desktop )

ExitApp





Expose_Show:

   if Expose_ListWin() {            ; show thumbs only if there's at least one window
      SetStretchBltMode( hdc_thumbnails, 4 )
      Gui Show
      if Wallpaper_IsNew() {      ; updates GUI if wallpaper has changed
         PaintDesktop( hdc_frontbuffer )
         BitBlt( hdc_desktop, 0, 0, A_ScreenWidth, A_ScreenHeight, hdc_frontbuffer, 0, 0, 0xCC0020 )
         }
      Expose_ShowWin()
   }

Return



Wallpaper_IsNew()
{

Static   wallpaper_last

   RegRead, wallpaper, HKEY_CURRENT_USER, Control Panel\Desktop, Wallpaper
   if (wallpaper <> wallpaper_last) {
      wallpaper_last := wallpaper
      return   true
   }

}




Expose_ListWin()
{

Global   Expose_ID

   WinGet id, list
   win_list :=
   Loop %id% {
      win_id := id%A_Index%
      WinGet, style, Style, ahk_id %win_id%         ; ignore windows without title bar
      WinGet, state, MinMax, ahk_id %win_id%      ; ignore minimized windows
      if ( style & 0xC00000 ) and ( state <> "-1" ) and ( win_id <> Expose_ID )
         win_list := win_list . win_id . ","
   }
   StringTrimRight win_list, win_list, 1
   Sort win_list, D,   ; keep positions of thumbnails
   Return win_list
}



Expose_ShowWin()
{

Global   Expose_ID
      , Expose_Cols
      , Expose_Rows
      , Expose_WIN0
      , Expose_Border
      , hdc_frontbuffer
      , hdc_printwindow
      , hdc_thumbnails
      , hdc_desktop

         win_list := Expose_ListWin()         ; get list of windows' id
         StringSplit, num_win, win_list, `,
         num_win := num_win0               ; count windows

         Expose_Cols := ceil(sqrt(num_win))
         Expose_Rows := ceil(num_win / Expose_Cols)

         thumb_w := A_ScreenWidth  // Expose_Cols
         thumb_h := A_ScreenHeight // Expose_Rows
         screen_ratio := A_ScreenWidth / A_ScreenHeight * Expose_Rows / Expose_Cols

         Loop Parse, win_list, `,
         {
            Expose_WIN%A_Index% := A_LoopField         ; store window's id
            WinGetPos,,, w%A_Index%, h%A_Index%, ahk_id %A_LoopField%
            win_ratio := w%A_Index% / h%A_Index%
            If (win_ratio < screen_ratio) {      ; tall window
               thumb_h%A_Index% := thumb_h - 2*Expose_Border
               thumb_w%A_Index% := Floor(thumb_w * win_ratio / screen_ratio) - 2*Expose_Border
            }
            Else {                                 ; wide window
               thumb_w%A_Index% := thumb_w - 2*Expose_Border
               thumb_h%A_Index% := Floor(thumb_h * screen_ratio / win_ratio) - 2*Expose_Border
            }
            if ( thumb_w%A_Index% > w%A_Index% or thumb_h%A_Index% > h%A_Index% ) {
               thumb_w%A_Index% := w%A_Index%
               thumb_h%A_Index% := h%A_Index%
            }
         }
         BitBlt( hdc_thumbnails, 0, 0, A_ScreenWidth, A_ScreenHeight, hdc_desktop, 0, 0 , 0xCC0020)

      Loop %num_win% {
         pos_x := thumb_w * Mod(A_Index-1,Expose_Cols)
         pos_y := thumb_h * ((A_Index-1)//Expose_Cols)

         PrintWindow( Expose_WIN%A_Index%, hdc_printwindow, 0) ; 0=window, 1=Child(no toolbars)
         hdc_target := hdc_thumbnails

         StretchBlt( hdc_target , pos_x + ( thumb_w - thumb_w%A_Index% ) // 2
                     , pos_y + ( thumb_h - thumb_h%A_Index% ) // 2
                     , thumb_w%A_Index%
                     , thumb_h%A_Index%
                     ,hdc_printwindow, 0, 0, w%A_Index%, h%A_Index% ,0xCC0020) ; SRCCOPY
         BitBlt( hdc_frontbuffer, 0 , 0 , A_ScreenWidth, A_ScreenHeight ,hdc_thumbnails,  0 , 0 , 0xCC0020) ; flip
       }
}



Expose_Hide:

   MouseGetPos x, y
   Gui, Hide
   win_id := 1 + x*Expose_Cols//A_ScreenWidth + y*Expose_Rows//A_ScreenHeight * Expose_Cols
   win_id := Expose_WIN%win_id%
   WinActivate,ahk_id %win_id%
   ; WinGetPos,,, x, y, A
   ; MouseMove, x/2, y/2

Return




; --------------------------------------------------------------------------------------------------
; Library: no need to modify below

; Libary (could be put in extra file )
; #include <GDI.ahk>
; for documentation of commands see: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/wingdistart_9ezp.asp

; -- highlevel not direct dllcall mapping , simplifiers
CreateDCBuffer(ByRef hdc_from, ByRef hdc_to, ByRef hbm_to, w ,h ) {
   ; does not work, something wrong with ByRef and global
   hdc_to  := CreateCompatibleDC(hdc_from) ; buffer
   hbm_to  := CreateCompatibleBitmap(hdc_from,w,h)
   old     := SelectObject(hdc_to,hbm_to)
}

; -- mfc wrapper
GetDC( hw ) {
   return DLLCall("GetDC", UInt, hw )
}

CreateDC( driver,device,output,mode  ) {
   return DLLCall("GetDC", UInt, driver, UInt, device, UInt, output, UInt, mode )
}

SetStretchBltMode( hdc , value ) {
     return DllCall("gdi32.dll\SetStretchBltMode", UInt,hdc, "int",value)
}

CreateCompatibleDC( hdc ) {
   return DllCall("gdi32.dll\CreateCompatibleDC", UInt,hdc)
}

CreateCompatibleBitmap( hdc , w, h ) {
     return DllCall("gdi32.dll\CreateCompatibleBitmap", UInt,hdc, Int,w, Int,h)
}

SelectObject( hdc , hbm ) {
   return DllCall("gdi32.dll\SelectObject", UInt,hdc, UInt,hbm)
}

DeleteObject( hbm ) {
   return DllCall("gdi32.dll\DeleteObject", UInt,hbm)   
}

DeleteDC( hdc ) {
   return DllCall("gdi32.dll\DeleteDC", UInt,hdc )
}

ReleaseDC( hwnd, hdc ) {
   return DllCall("gdi32.dll\ReleaseDC", UInt,hwnd,UInt,hdc )
}

PrintWindow( window_id , hdc , mode ) {
   return DllCall("PrintWindow", UInt, window_id , UInt,hdc, UInt, mode)
}

StretchBlt( hdc_dest , x1, y1, w1, h1, hdc_source , x2, y2, w2, h2 , mode) {
   return DllCall("gdi32.dll\StretchBlt"
          , UInt,hdc_dest  , Int,x1, Int,y1, Int,w1, Int,h1
             , UInt,hdc_source, Int,x2, Int,y2, Int,w2, Int,h2
          , UInt,mode)
}

BitBlt( hdc_dest, x1, y1, w1, h1 , hdc_source, x2, y2 , mode ) {
   return DllCall("gdi32.dll\BitBlt"
          , UInt,hdc_dest   , Int, x1, Int, y1, Int, w1, Int, h1
             , UInt,hdc_source    , Int, x2, Int, y2
          , UInt, mode)
}

PaintDesktop(  hdc ) {
   return DllCall("PaintDesktop", UInt, hdc )
}

; constants
; see: http://www.adaptiveintelligence.net/Developers/Reference/Win32API/GDIConstants.aspx
; #SRCCOPY = 0xCC0020

      if ( style & 0xC00000 ) and ( state <> "-1" ) and ( win_id <> Expose_ID )

      WinGetPos,,,w,, ahk_id %win_id%
      if  (style & 0x800000) and (w>0) and ( state <> "-1" ) and ( win_id <> Expose_ID )