Actual Screen Size Not resolution?

[Chimaera]

Ok what im trying to find is a way to give me the actual screen size

e.g. 15.4", 15.6", 17" etc

This will be used primarily for laptops

Is there a way to calculate it from Desktop resolution maybe?

Or is it held anywhere o the pc registry etc?

Ive been looking round and the only thing i could find was a reference to this

and using

JSThePatriot script CompInfo

"PixelsPerXLogicalInch: "

"PixelsPerYLogicalInch: "

and

"ScreenHeight: "

"ScreenWidth: "

from the _ComputerGetMonitors() section it gives me

96 for both the pixels per inch

1920 x 1080 for the other two

1920 / 96 = 20

1080 / 96 = 11.25

This is close but not accurate and im not sure how a diagonal could be calculated from the results?

Any ideas

Edited May 5, 2012 by Chimaera

[UEZ]

Have in mind the size of the physical pixel....

#include <GDIPlus.au3>
_GDIPlus_Startup()
ConsoleWrite(ScreenSize()  & " inch" & @CRLF)
_GDIPlus_Shutdown()

Func ScreenSize()
    Local $hGraphic = _GDIPlus_GraphicsCreateFromHWND(0)
    $aDPI_w = DllCall($ghGDIPDll, "uint", "GdipGetDpiX", "handle", $hGraphic, "float*", 0)
    $aDPI_h = DllCall($ghGDIPDll, "uint", "GdipGetDpiY", "handle", $hGraphic, "float*", 0)
    _GDIPlus_GraphicsDispose($hGraphic)
    Return Round(Pixel_Distance(0, 0, @DesktopWidth, @DesktopHeight) / $aDPI_w[2], 2)
EndFunc

Func Pixel_Distance($x1, $y1, $x2, $y2) ;Pythagoras theorem
    Local $a, $b
    If $x2 = $x1 And $y2 = $y1 Then Return 0
    $a = $y2 - $y1
    $b = $x2 - $x1
    Return Sqrt($a * $a + $b * $b)
EndFunc   ;==>Pixel_Distance

Br,

UEZ

Edited May 5, 2012 by UEZ

[Chimaera]

The math in there makes my head spin, i looked up the therom on Google but geez difficult stuff

That works except it returns 22.95 inch

Yet my monitor is 24 inch

How do i reconcile the difference?

Edit and is it because im using a desktop?

Edited May 6, 2012 by Chimaera

[czardas]

I'm not sure about the absolute screen dimensions but you can easily calculate the diagonal using Pythagoras' Theorem.

$iDesktopDiagonal = (@DesktopWidth^2 + @DesktopHeight^2)^.5

MsgBox(0, "Desktop Dimensions", _
"Width" & @TAB & @DesktopWidth & @LF & _
"Height" & @TAB & @DesktopHeight & @LF & _
"Diagonal" & @TAB & $iDesktopDiagonal)

[UEZ]

The math in there makes my head spin, i looked up the therom on Google but geez difficult stuff

That works except it returns 22.95 inch

Yet my monitor is 24 inch

How do i reconcile the difference?

Edit and is it because im using a desktop?

As I mentioned before it depends on the physical pixel size.

E.g. a notebooks screen is a 17" screen and can display 1920x1080 and a monitor is a 22" with same resolution. You see calculating the pixels size at a specific DPI cannot give you the exact screen size.

@czardas: look at the Pixel_Distance() function above.

Br,

UEZ

Edited May 6, 2012 by UEZ

[Chimaera]

So the pixels are different sizes depending on the monitor?

Did i get that right?

So if i run it on a laptop on tue when i get back to work it should be right. or closer as i get its never going to be exact.

[UEZ]

I do not know another way where the pixel size is saved somewhere in the system.

Br,

UEZ

[KaFu]

There is a Vista+ WMI class called WmiMonitorBasicDisplayParams. This one comes pretty close for my primary display (reports 27,15" for my 27"), but sadly it completely fails for my secondary (TV) display (reports 28,9" for my 47").

_WmiMonitorBasicDisplayParams()

Func _WmiMonitorBasicDisplayParams()
    Local $strcomputer = "."
    Local $objWMIServiceWMI = ObjGet("winmgmts:" & "{impersonationLevel=impersonate}!" & $strcomputer & "rootWMI")
    If IsObj($objWMIServiceWMI) Then
        ; http://msdn.microsoft.com/en-us/library/windows/desktop/aa394535%28v=vs.85%29.aspx
        $WMIWmiMonitorID = $objWMIServiceWMI.ExecQuery("SELECT * FROM WmiMonitorBasicDisplayParams WHERE Active='True'")
        For $objComputer In $WMIWmiMonitorID
            ConsoleWrite($objComputer.MaxHorizontalImageSize & @CRLF)
            ConsoleWrite($objComputer.MaxVerticalImageSize & @CRLF)
            ConsoleWrite((Pixel_Distance(0, 0, $objComputer.MaxHorizontalImageSize, $objComputer.MaxVerticalImageSize) / 2.54) & @CRLF & @CRLF)
        Next
    EndIf
EndFunc   ;==>_WmiMonitorBasicDisplayParams

Func Pixel_Distance($x1, $y1, $x2, $y2) ;Pythagoras theorem
    Local $a, $b
    If $x2 = $x1 And $y2 = $y1 Then Return 0
    $a = $y2 - $y1
    $b = $x2 - $x1
    Return Sqrt($a * $a + $b * $b)
EndFunc   ;==>Pixel_Distance

Edited May 6, 2012 by KaFu

[Chimaera]

Many thanks for the help guys

[czardas]

@czardas: look at the Pixel_Distance() function above.

LOL I didn't recognize it. I never knew about the function Sqrt(), who would have thought it!

Edited May 7, 2012 by czardas

[Chimaera]

A little update

I did some testing at work on a number of laptops and one desktop on kafu's suggestion

And these were the results

Desktop

MaxHorizontalImageSize 34 / MaxVerticalImageSize 27 / Resolution 1280 x 1024 / Result 17.11 Actual = 34.1 | 27.3 [17.0"]

Laptop

MaxHorizontalImageSize 31 / MaxVerticalImageSize 19 / Resolution 1366 x 768 / Result 15.35 Actual = 34.6(cm)| 19.8(cm) [15.6"]

MaxHorizontalImageSize 33 / MaxVerticalImageSize 21 / Resolution 1280 x 800 / Result 15.41 Actual = 33.1(cm) | 20.8(cm) [15.4"]

MaxHorizontalImageSize 33 / MaxVerticalImageSize 21 / Resolution 1280 x 1024 / Result 15.41 Actual = 33.1(cm)| 20.9(cm) [15.4"]

MaxHorizontalImageSize 38 / MaxVerticalImageSize 21 / Resolution 1600 x 900 / Result 17.11 Actual = 38.2(cm) | 21.5(cm) [17.3"]

MaxHorizontalImageSize 34 / MaxVerticalImageSize 19 / Resolution 1366 x 768 / Result 15.35 Actual = 34.4(cm) | 19.5(cm) [15.6"]

MaxHorizontalImageSize 34 / MaxVerticalImageSize 19 / Resolution 1366 x 768 / Result 15.35 Actual = 34.4(cm) | 19.5(cm) [15.6"]

MaxHorizontalImageSize 37 / MaxVerticalImageSize 23 / Resolution 1440 x 900 / Result 17.17 Actual = 36.8(cm) | 23.1(cm) [17.0"]

Thought i would post them just so you guys can see them

[UEZ]

Thanks for the testing and results.

Overall a good approximation!

Br,

UEZ

Edited May 8, 2012 by UEZ

[Chimaera]

Im probably going to have to have a if its between these figures then call it 15.4 etc etc scenario to make it workable in the end.

But ill run some more tests first