Graphics/Win32/LayeredWindow.hsc
{-# LANGUAGE CPP #-}
{- |
Module : Graphics.Win32.LayeredWindow
Copyright : 2012-2013 shelarcy
License : BSD-style
Maintainer : shelarcy@gmail.com
Stability : Provisional
Portability : Non-portable (Win32 API)
Provides LayeredWindow functionality.
-}
module Graphics.Win32.LayeredWindow (module Graphics.Win32.LayeredWindow, Graphics.Win32.Window.c_GetWindowLongPtr ) where
import Control.Monad ( void )
import Data.Bits ( (.|.) )
import Foreign.Ptr ( Ptr )
import Graphics.Win32.GDI.AlphaBlend ( BLENDFUNCTION )
import Graphics.Win32.GDI.Types ( COLORREF, HDC, SIZE, SIZE, POINT )
import Graphics.Win32.Window ( WindowStyleEx, c_GetWindowLongPtr, c_SetWindowLongPtr )
import System.Win32.Types ( DWORD, HANDLE, BYTE, BOOL, INT )
#include <windows.h>
##include "windows_cconv.h"
#include "winuser_compat.h"
toLayeredWindow :: HANDLE -> IO ()
toLayeredWindow w = do
flg <- c_GetWindowLongPtr w gWL_EXSTYLE
void $ c_SetWindowLongPtr w gWL_EXSTYLE (flg .|. (fromIntegral wS_EX_LAYERED))
-- test w = c_SetLayeredWindowAttributes w 0 128 lWA_ALPHA
gWL_EXSTYLE :: INT
gWL_EXSTYLE = #const GWL_EXSTYLE
wS_EX_LAYERED :: WindowStyleEx
wS_EX_LAYERED = #const WS_EX_LAYERED
lWA_COLORKEY, lWA_ALPHA :: DWORD
lWA_COLORKEY = #const LWA_COLORKEY
lWA_ALPHA = #const LWA_ALPHA
foreign import WINDOWS_CCONV unsafe "windows.h SetLayeredWindowAttributes"
c_SetLayeredWindowAttributes :: HANDLE -> COLORREF -> BYTE -> DWORD -> IO BOOL
foreign import WINDOWS_CCONV unsafe "windows.h GetLayeredWindowAttributes"
c_GetLayeredWindowAttributes :: HANDLE -> COLORREF -> Ptr BYTE -> Ptr DWORD -> IO BOOL
foreign import WINDOWS_CCONV unsafe "windows.h UpdateLayeredWindow"
c_UpdateLayeredWindow :: HANDLE -> HDC -> Ptr POINT -> Ptr SIZE -> HDC -> Ptr POINT -> COLORREF -> Ptr BLENDFUNCTION -> DWORD -> IO BOOL
#{enum DWORD,
, uLW_ALPHA = ULW_ALPHA
, uLW_COLORKEY = ULW_COLORKEY
, uLW_OPAQUE = ULW_OPAQUE
}