How to change the refresh rate?

[VicTT]

Does anyone know how?DllCall what?

[cppman]

I would download a graphix library... then do a dll call to the dll they provide... usually they will only give u a c++ or c++ like language example.. so its gonna be kinda hard... but yeah, just download a small graphics library, and do a dll call to the dll they provide...

[Oxin8]

ChangeDisplaySettings. Here you go! Edited February 23, 2006 by Oxin8

[GaryFrost]

this is an updated version from Larry to work with latest beta, might need some more work

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Opt("MustDeclareVars", 1)

_Main()

Func _Main()
    Local $width, $height, $bpp, $freq
    
;~ $a = DisplayEnumRes(0, $width, $height, $bpp, $freq)
;~ MsgBox(4096,$a,$width & @LF & $height & @LF & $bpp & @LF & $freq)
    
;~ $a = DisplayEnumRes(1, $width, $height, $bpp, $freq)
;~ MsgBox(4096,$a,$width & @LF & $height & @LF & $bpp & @LF & $freq)
    
    MsgBox(4096, "", DisplayChangeRes(1024, 768, 32, 60))
    
    MsgBox(4096, "", DisplayChangeRes(1024, 768, 32, 75))
EndFunc  ;==>_Main

Func DisplayEnumRes($index, ByRef $width, ByRef $height, ByRef $bpp, ByRef $freq)
    Local $DEVMODE = DllStructCreate("byte[32];int[10];byte[32];int[6]")
    
    Local $b = DllCall("user32.dll", "int", "EnumDisplaySettings", "ptr", 0, "long", $index, "ptr", DllStructGetPtr($DEVMODE))
    
    If @error Then
        $b = 0
    Else
        $b = $b[0]
    EndIf
    
    If $b <> 0 Then
        $width = DllStructGetData($DEVMODE, 4, 2)
        $height = DllStructGetData($DEVMODE, 4, 3)
        $bpp = DllStructGetData($DEVMODE, 4, 1)
        $freq = DllStructGetData($DEVMODE, 4, 5)
    EndIf
    
    $DEVMODE = 0
    
    Return $b
EndFunc  ;==>DisplayEnumRes

Func DisplayChangeRes($width, $height, $bpp, $freq)
    Local Const $DM_PELSWIDTH = 0x00080000
    Local Const $DM_PELSHEIGHT = 0x00100000
    Local Const $DM_BITSPERPEL = 0x00040000
    Local Const $DM_DISPLAYFREQUENCY = 0x00400000
    Local Const $CDS_TEST = 0x00000002
    Local Const $CDS_UPDATEREGISTRY = 0x00000001
    Local Const $DISP_CHANGE_RESTART = 1
    Local Const $DISP_CHANGE_SUCCESSFUL = 0
    Local Const $HWND_BROADCAST = 0xffff
    Local Const $WM_DISPLAYCHANGE = 0x007E
    
    Local $DEVMODE = DllStructCreate("byte[32];int[10];byte[32];int[6]")
    
    Local $b = DllCall("user32.dll", "int", "EnumDisplaySettings", "ptr", 0, "long", 0, "ptr", DllStructGetPtr($DEVMODE))
    If @error Then
        $b = 0
    Else
        $b = $b[0]
    EndIf
    If $b <> 0 Then
        DllStructSetData($DEVMODE, 2, BitOR($DM_PELSWIDTH, $DM_PELSHEIGHT, $DM_BITSPERPEL, $DM_DISPLAYFREQUENCY), 5)
        DllStructSetData($DEVMODE, 4, $width, 2)
        DllStructSetData($DEVMODE, 4, $height, 3)
        DllStructSetData($DEVMODE, 4, $bpp, 1)
        DllStructSetData($DEVMODE, 4, $freq, 5)
        
        $b = DllCall("user32.dll", "int", "ChangeDisplaySettings", "ptr", DllStructGetPtr($DEVMODE), "int", $CDS_TEST)
        
        If @error Then
            $b = -1
        Else
            $b = $b[0]
        EndIf
        
        Select
            Case $b = $DISP_CHANGE_RESTART
                $DEVMODE = 0
                Return 2
            Case $b = $DISP_CHANGE_SUCCESSFUL
                DllCall("user32.dll", "int", "ChangeDisplaySettings", "ptr", DllStructGetPtr($DEVMODE), "int", $CDS_UPDATEREGISTRY)
                DllCall("user32.dll", "int", "SendMessage", "hwnd", $HWND_BROADCAST, "int", $WM_DISPLAYCHANGE, _
                        "int", $bpp, "int", $height * 2 ^ 16 + $width)
                $DEVMODE = 0
                Return 1
            Case Else
                $DEVMODE = 0
                Return $b
        EndSelect
    EndIf
EndFunc  ;==>DisplayChangeRes

#cs
    Func DisplayChangeDPI($dpi)
    {
    DEVMODE DevM;
    long ret;
    
    EnumDisplaySettings(NULL,0,&DevM);
    
    DevM.dmFields = DM_LOGPIXELS;
    DevM.dmLogPixels = dpi;
    
    ret = ChangeDisplaySettings(&DevM, CDS_TEST);
    
    switch(ret)
    {
    case DISP_CHANGE_RESTART:
    return 2;
    case DISP_CHANGE_SUCCESSFUL:
    ChangeDisplaySettings(&DevM, CDS_UPDATEREGISTRY);
    SendMessage(HWND_BROADCAST, WM_DISPLAYCHANGE, (WPARAM)DevM.dmBitsPerPel, (LPARAM)(DevM.dmPelsHeight * 2 ^ 16 + DevM.dmPelsWidth));
    return 1;
    default:
    return 0;
    }
    }
#ce

Edited February 23, 2006 by gafrost

[The_Noob]

Is there a way to change the DPI for only one running program? like if i have a game i want to run at 90 dpi, while my desktop is running at 120 dpi, how would i do that?

[Bert]

You could use a script to start the game. Have it first change the refresh rate, then start the game. When you close the game, have it change it back, then exit the script. Maybe something like this:

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Opt("MustDeclareVars", 1)
dim $width, $height, $bpp, $freq
DisplayChangeRes($width, $height, $bpp, $freq) ;changes to refresh for game
runwait("The name of game", "Path")
DisplayChangeRes($width, $height, $bpp, $freq) ;changes to refresh for normal use
exit

Func DisplayEnumRes($index, ByRef $width, ByRef $height, ByRef $bpp, ByRef $freq)
    Local $DEVMODE = DllStructCreate("byte[32];int[10];byte[32];int[6]")
    
    Local $b = DllCall("user32.dll", "int", "EnumDisplaySettings", "ptr", 0, "long", $index, "ptr", DllStructGetPtr($DEVMODE))
    
    If @error Then
        $b = 0
    Else
        $b = $b[0]
    EndIf
    
    If $b <> 0 Then
        $width = DllStructGetData($DEVMODE, 4, 2)
        $height = DllStructGetData($DEVMODE, 4, 3)
        $bpp = DllStructGetData($DEVMODE, 4, 1)
        $freq = DllStructGetData($DEVMODE, 4, 5)
    EndIf
    
    $DEVMODE = 0
    
    Return $b
EndFunc  ;==>DisplayEnumRes

Func DisplayChangeRes($width, $height, $bpp, $freq)
    Local Const $DM_PELSWIDTH = 0x00080000
    Local Const $DM_PELSHEIGHT = 0x00100000
    Local Const $DM_BITSPERPEL = 0x00040000
    Local Const $DM_DISPLAYFREQUENCY = 0x00400000
    Local Const $CDS_TEST = 0x00000002
    Local Const $CDS_UPDATEREGISTRY = 0x00000001
    Local Const $DISP_CHANGE_RESTART = 1
    Local Const $DISP_CHANGE_SUCCESSFUL = 0
    Local Const $HWND_BROADCAST = 0xffff
    Local Const $WM_DISPLAYCHANGE = 0x007E
    
    Local $DEVMODE = DllStructCreate("byte[32];int[10];byte[32];int[6]")
    
    Local $b = DllCall("user32.dll", "int", "EnumDisplaySettings", "ptr", 0, "long", 0, "ptr", DllStructGetPtr($DEVMODE))
    If @error Then
        $b = 0
    Else
        $b = $b[0]
    EndIf
    If $b <> 0 Then
        DllStructSetData($DEVMODE, 2, BitOR($DM_PELSWIDTH, $DM_PELSHEIGHT, $DM_BITSPERPEL, $DM_DISPLAYFREQUENCY), 5)
        DllStructSetData($DEVMODE, 4, $width, 2)
        DllStructSetData($DEVMODE, 4, $height, 3)
        DllStructSetData($DEVMODE, 4, $bpp, 1)
        DllStructSetData($DEVMODE, 4, $freq, 5)
        
        $b = DllCall("user32.dll", "int", "ChangeDisplaySettings", "ptr", DllStructGetPtr($DEVMODE), "int", $CDS_TEST)
        
        If @error Then
            $b = -1
        Else
            $b = $b[0]
        EndIf
        
        Select
            Case $b = $DISP_CHANGE_RESTART
                $DEVMODE = 0
                Return 2
            Case $b = $DISP_CHANGE_SUCCESSFUL
                DllCall("user32.dll", "int", "ChangeDisplaySettings", "ptr", DllStructGetPtr($DEVMODE), "int", $CDS_UPDATEREGISTRY)
                DllCall("user32.dll", "int", "SendMessage", "hwnd", $HWND_BROADCAST, "int", $WM_DISPLAYCHANGE, _
                        "int", $bpp, "int", $height * 2 ^ 16 + $width)
                $DEVMODE = 0
                Return 1
            Case Else
                $DEVMODE = 0
                Return $b
        EndSelect
    EndIf
EndFunc  ;==>DisplayChangeRes

I didn't test this. You may need to tweak it.

Edited September 23, 2006 by vollyman