_GDIPlus_ImageLoadFromFile & _GDIPlus_GraphicsDrawImageRect

[JackDinn]

maybe iv got a mental block today but i cant figure out how to get to the alpha channel of an image that was loaded from a file ?

$Himage=_GDIPlus_ImageLoadFromFile($file)

_GDIPlus_GraphicsDrawImageRect($buffer,$Himage,.......)

whereas if im using a brush to _GDIPlus_GraphicsFillRect($buffer,........,$brush) i can set the alpha when making the brush.

tried setting the files transparency in photoshop before i save it but that dont work.

what am i missing.

thx all.

[UEZ]

Do you want to display an transparent image? If yes, try this:

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#include <GUIConstantsEx.au3>
#include <WindowsConstants.au3>
#include <GDIPlus.au3>

Global $hGUI, $hImage, $hGraphic, $hImage
Global Const $SC_DRAGMOVE = 0xF012
_GDIPlus_Startup()
; Load PNG image
$hImage = _GDIPlus_ImageLoadFromFile("..\..\Images\Audiograbber_512x512_transparent.png")
$iWidth = _GDIPlus_ImageGetWidth($hImage)
$iHeight = _GDIPlus_ImageGetHeight($hImage)

; Create GUI
$hGUI = GUICreate("Show PNG", $iWidth, $iHeight, -1, -1, $WS_POPUP, $WS_EX_LAYERED + $WS_EX_TOPMOST)
$hGUI_child = GUICreate("", $iWidth, $iHeight, 0, 0, $WS_POPUP, $WS_EX_LAYERED + $WS_EX_TOPMOST + $WS_EX_MDICHILD, $hGUI)
$hButton = GUICtrlCreateButton("Exit", $iWidth * 2 / 3, $iHeight * 2 / 3, 40, 40)
GUISetBkColor(0xFFFFFF, $hGUI_child)
GUISetState(@SW_SHOW, $hGUI)
GUISetState(@SW_SHOW, $hGUI_child)
SetTransparentBitmap($hGUI, $hImage)
_WinAPI_SetLayeredWindowAttributes($hGUI_child, 0xFFFFFF, 0xff)

$hGraphic = _GDIPlus_GraphicsCreateFromHWND($hGUI_child)
_GDIPlus_GraphicsSetSmoothingMode($hGraphic, 2)
_GDIPlus_GraphicsDrawString($hGraphic, "GDI+ Full Transparency", 0, $iHeight / 2 - 20, "Arial", 24)

GUIRegisterMsg($WM_LBUTTONDOWN, "_WM_LBUTTONDOWN")

While 1
    $nMsg = GUIGetMsg()
    Switch $nMsg
        Case $GUI_EVENT_CLOSE, $hButton
            GUIRegisterMsg($WM_LBUTTONDOWN, "")
            _GDIPlus_ImageDispose($hImage)
            _GDIPlus_GraphicsDispose($hGraphic)
            _GDIPlus_Shutdown()
            GUIDelete($hGUI)
            ExitLoop
    EndSwitch
WEnd

Func _WM_LBUTTONDOWN($hWnd, $iMsg, $wParam, $lParam)
    _SendMessage($hGUI, $WM_SYSCOMMAND, $SC_DRAGMOVE, 0)
EndFunc   ;==>_WM_LBUTTONDOWN

Func SetTransparentBitmap($hGUI, $hImage, $iOpacity = 0xFF)
    Local $hScrDC, $hMemDC, $hBitmap, $hOld, $pSize, $tSize, $pSource, $tSource, $pBlend, $tBlend
    $hScrDC = _WinAPI_GetDC(0)
    $hMemDC = _WinAPI_CreateCompatibleDC($hScrDC)
    $hBitmap = _GDIPlus_BitmapCreateHBITMAPFromBitmap($hImage)
    $hOld = _WinAPI_SelectObject($hMemDC, $hBitmap)
    $tSize = DllStructCreate($tagSIZE)
    $pSize = DllStructGetPtr($tSize)
    DllStructSetData($tSize, "X", _GDIPlus_ImageGetWidth($hImage))
    DllStructSetData($tSize, "Y", _GDIPlus_ImageGetHeight($hImage))
    $tSource = DllStructCreate($tagPOINT)
    $pSource = DllStructGetPtr($tSource)
    $tBlend = DllStructCreate($tagBLENDFUNCTION)
    $pBlend = DllStructGetPtr($tBlend)
    DllStructSetData($tBlend, "Alpha", $iOpacity)
    DllStructSetData($tBlend, "Format", 1)
    _WinAPI_UpdateLayeredWindow($hGUI, $hGUI, 0, $pSize, $hMemDC, $pSource, 0, $pBlend, $ULW_ALPHA)
    _WinAPI_ReleaseDC(0, $hScrDC)
    _WinAPI_SelectObject($hMemDC, $hOld)
    _WinAPI_DeleteObject($hBitmap)
    _WinAPI_DeleteDC($hMemDC)
EndFunc   ;==>SetTransparentBitmap

Or this:

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#include <GUIConstantsEx.au3>
#include <WindowsConstants.au3>
#include <GDIPlus.au3>

Global $hGUI, $hImage, $hGraphic, $hImage
Global Const $SC_DRAGMOVE = 0xF012
_GDIPlus_Startup()
; Load PNG image
$hImage = _GDIPlus_ImageLoadFromFile("..\Images\Audiograbber_512x512_transparent.png")
$iWidth = _GDIPlus_ImageGetWidth($hImage)
$iHeight = _GDIPlus_ImageGetHeight($hImage)

; Create GUI
$hGUI = GUICreate("Show PNG", $iWidth, $iHeight, -1, -1, Default, $WS_EX_TOPMOST)
GUISetState(@SW_SHOW, $hGUI)

$hGraphic = _GDIPlus_GraphicsCreateFromHWND($hGUI)
_GDIPlus_GraphicsDrawImageRect ($hGraphic, $hImage, 0, 0, $iWidth, $iHeight);copy bitmap to GUI

GUIRegisterMsg($WM_LBUTTONDOWN, "_WM_LBUTTONDOWN")

While 1
    $nMsg = GUIGetMsg()
    Switch $nMsg
        Case $GUI_EVENT_CLOSE
            GUIRegisterMsg($WM_LBUTTONDOWN, "")
            _GDIPlus_ImageDispose($hImage)
            _GDIPlus_GraphicsDispose($hGraphic)
            _GDIPlus_Shutdown()
            GUIDelete($hGUI)
            ExitLoop
    EndSwitch
WEnd

Func _WM_LBUTTONDOWN($hWnd, $iMsg, $wParam, $lParam)
    _SendMessage($hGUI, $WM_SYSCOMMAND, $SC_DRAGMOVE, 0)
EndFunc   ;==>_WM_LBUTTONDOWN

Just replace $hImage with a transparent png image and start script.

Br,

UEZ

[JackDinn]

yea you got it, looks like i wasn't missing anything it was just harder than i expected :-/

But i think your UDF SetTransparentBitmap() is exactly what i am after.

I shall go and have a closer look.

Many thx UEZ, appreciated.

20 mins later ...

your _WinAPI_SetLayeredWindowAttributes($hGUI_child, 0xFFFFFF, 0xff) should have 4 arguments according to my version of WinAPIEx.au3

so i just guessed and used _WinAPI_SetLayeredWindowAttributes($hGUI_child, 0xFFFFFF, 0xff, $LWA_ALPHA)

and for some reason iv just noticed that my WindowsConstants.au3 does not have WM_LBUTTONDOWN so i used $NM_LDOWN. how come ? its a standard message code, it should be in there shouldn't it ?

However after getting it to work it did show the button and the text contained in a white box that was the size of my .png but no sigh of the picture ?

thx for your work.