How to draw fullscreen in GDI and change screen res temporarily?

[kroz]

I've made a small gdi proggie and would like to make it run fullscreen
in 640x480 mode.

i would like to know how to :

(A) make the program run in fullscreen

(B) how to set the screen-res to 640x480 so the program is not just
    a tiny square on a nice 1024x768 screen ( kinda like stretch-to-fit, except not changing the aspect ratio )

any help/code/(ranting?) would be appreciated very much :)

[Bill Cravener]

How too:
http://msdn.microsoft.com/en-us/library/windows/desktop/dd183411(v=vs.85).aspx

Example:
http://www.quickersoft.com/examples/Resolution.zip

[kroz]

thanks. unfortunately - it doesnt look like I can get 640x480 in Win7 :( bummer.
and any examples on creating a fullscreen window?
and can it be done from a DialogBox? (i.e the kind that's in the resources called by DialogBoxParam )

[sinsi]

If you mean full screen as in no window, I think you are restricted to directx.

[dedndave]

you can use a window handle of HWND_DESKTOP, which is 0
of course, you mess up their desktop - lol

or - you can create a borderless window that is the size of the screen at coord 0,0

you can get the window size with GetSystemMetrics
but - if you want the workspace - SystemParametersInfo has that
the workspace excludes things like taskbars

then, there is always a borderless, captionless window that is maximized

oh - and you can use EnumDisplaySettings to get the supported screen resolutions

[Bill Cravener]

thanks. unfortunately - it doesnt look like I can get 640x480 in Win7 :( bummer.

On both my Win7 and XP boxes 800x600 is the minimum resolution. I run both my machines in 1920x1080 resolution.

[kroz]

Hrmmm...
Yes, GDI can be done fullscreen i think, but getting fullscreen at 768p brings up lots of complications with the demo i'm making :/

and another question to save starting another thread,
if i create a timer using SetTimer to tick every 1000ms or whatever,
will the tick time be the same on all (or 99.9%) of computers?
(since one of my computers seems to be running too fast with a timer-operated animation)

[MichaelW]

I have never seen a system where the timer frequencies were off by any noticeable amount. I think there could be conditions where the timers might be slowed, for example a single-core system where the core is being monopolized by a very high-priority process, but I can't think of any conditions where the timers would speed up.

[dedndave]

you may also have a condition where the machine in question cannot keep up with the code   :P

[Farabi]

Try this code, it worked on my XP, Visa and 7

Code Select Expand


Change_Screen_Resolution proc w:dword, h:dword, bitsPerPixel:dword
invoke RtlZeroMemory, addr _dmScreenSettings, sizeof DEVMODE
mov _dmScreenSettings.dmSize, sizeof DEVMODE
mov _dmScreenSettings.dmPelsWidth, CMEM(w)
mov _dmScreenSettings.dmPelsHeight, CMEM(h)
mov _dmScreenSettings.dmBitsPerPel, CMEM(bitsPerPixel)
mov _dmScreenSettings.dmFields, DM_BITSPERPEL or DM_PELSWIDTH or DM_PELSHEIGHT or DM_DISPLAYFREQUENCY
mov _dmScreenSettings.dmDisplayFrequency, 60
invoke ChangeDisplaySettings, addr _dmScreenSettings, 000000004h
.if eax != DISP_CHANGE_SUCCESSFUL
xor eax, eax
.else
mov eax, TRUE
.endif
ret
Change_Screen_Resolution endp


[hfheatherfox07]

@ kroz I think we covered this in the old masm forum here http://www.masmforum.com/board/index.php?topic=17221.0

with this attachments you can go to either full desk top or window  F1 to toggle in between them
I think this is what you are asking for  :t

[kroz]

thanks all :)
problem fixed.
not that i understood that code ... :P

[kroz]

Oh yes , How can I set the window to be a fixed size (not user-changeable) when in windowed mode ?
i.e - if you choose NO for fullscreen then you cannot resize window.
(BlankWindow5) :)

[jj2007]

For CreateWindowEx:
style=WS_OVERLAPPED or WS_CAPTION or WS_SYSMENU or WS_MINIMIZEBOX or WS_CLIPCHILDREN or WS_VISIBLE

[dedndave]

i think WS_OVERLAPPEDWINDOW includes the WS_THICKFRAME bit
WS_THICKFRAME means the window has a sizing border around it

but - if you want to keep the border - and still disable sizing...
you can respond to the WM_GETMINMAXINFO messages in the main window WndProc

Code Select Expand

    .elseif eax==WM_GETMINMAXINFO
        mov     edx,lParam
        mov     [edx].MINMAXINFO.ptMinTrackSize.x,MainWidth
        mov     [edx].MINMAXINFO.ptMinTrackSize.y,MainHeight
        mov     [edx].MINMAXINFO.ptMaxTrackSize.x,MainWidth
        mov     [edx].MINMAXINFO.ptMaxTrackSize.y,MainHeight
        xor     eax,eax
        ret

i normally only use the "Min" sizes to set minimum window dimensions
but, if you set the "Min"s = "Max"s, the window is stuck at that size

EDIT: changed WS_BORDER to WS_THICKFRAME per Jochen   :P