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Getting screenshot of Windows?
ITM
Member #798
November 2000
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Posted on 08/13/2004 2:08 AM   View Profile

I'm just wondering whether getting a screenshot of Windows is possible or not... (I mean getting the result of the associated keyboard touch) And if so, in what way? Can I do that without creating a winallegro application?

deps
Member #3,858
September 2003
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Posted on 08/13/2004 2:11 AM   View Profile

if you press printscreen, the screenshot is in the clipboard. just paste it.
And it is possible to create a winallegro application, there is code for it here somewhere, iirc.

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ITM
Member #798
November 2000
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Posted on 08/13/2004 2:20 AM   View Profile

Sorry, it wasn't clear...
I want to get that from an allegro program :)

miran
Member #2,407
June 2002
Posted on 08/13/2004 3:02 AM   View Profile

Take a look at the source of that screen breaking game spellcaster made a while ago. It grabs a Windows screenshot and then it lets you destroy it with a multitude of fun weapons. I can't remember what it's called right now, just look at spell's profile...

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FMC
Member #4,431
March 2004
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Posted on 08/13/2004 3:07 AM   View Profile

http://www.allegro.cc/depot/project.php?_id=861
is the project's page.

This is some relevant code that might help you:

1void grabDesktop() {
2 HWND hwnd;
3 HDC ddc;
4 RECT sz;
5 
6 hwnd = GetDesktopWindow();
7 ddc = GetDC(hwnd);
8 
9 GetWindowRect(hwnd, &sz);
10 
11 mdc = CreateCompatibleDC(ddc);
12 hbmp = CreateCompatibleBitmap(ddc, sz.right, sz.bottom);
13 SelectObject(mdc, hbmp);
14 BitBlt(mdc, 0, 0, sz.right, sz.bottom, ddc, 0, 0, SRCCOPY);
15 
16 
17 ReleaseDC(hwnd, ddc);
18}

[FMC Studios] - [Caries Field] - [Ctris] - [Pman] - [Chess for allegroites]
Written laws are like spiders' webs, and will, like them, only entangle and hold the poor and weak, while the rich and powerful will easily break through them. -Anacharsis
Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover. -Mark Twain

ITM
Member #798
November 2000
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Posted on 08/13/2004 3:17 AM   View Profile

Excellent, thanks a lot Mithrandir, I'm poor at windows programming :D
I'll check that as soon as possible once back at home !

FMC
Member #4,431
March 2004
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Posted on 08/13/2004 3:57 AM   View Profile

Glad of having helped, but remember that the code is not of my creation, Spellcaster did it :P

[FMC Studios] - [Caries Field] - [Ctris] - [Pman] - [Chess for allegroites]
Written laws are like spiders' webs, and will, like them, only entangle and hold the poor and weak, while the rich and powerful will easily break through them. -Anacharsis
Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover. -Mark Twain

spellcaster
Member #1,493
September 2001
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Posted on 08/13/2004 4:52 AM   View Profile

Well, while that part grabs the dektop, you should check the complete startup code. The order of the grabbing and the install calls is important.

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There are no stupid questions, but there are a lot of inquisitive idiots.

ITM
Member #798
November 2000
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Posted on 08/13/2004 4:30 PM   View Profile

Heh thanks a lot Spellcaster.. BTW, what's the command line that you use in order to compile it?

BAF
Member #2,981
December 2002
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Posted on 08/13/2004 5:04 PM   View Profile

with allegro static. Or edit the .c file and remove the define ALLEGRO_STATICLINK

i did that, and it worked for me w/ gcc agression.c -o agression -lalleg -mwindows

btw-- it segfaults here on the bitblt. :( i wanted to beat up my desktop too.

BAF.zone | SantaHack!

ITM
Member #798
November 2000
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Posted on 08/13/2004 5:33 PM   View Profile

I get weird errors like undefined reference to 'screen' or 'system_driver' if I add ALLEGRO_STATICLINK 1
Otherwise,it just crashes (4.1.15 WIP)

ReyBrujo
Moderator
January 2001
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Posted on 08/13/2004 5:37 PM   View Profile

What is your full command line?

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RB
光子「あたしただ…奪う側に回ろうと思っただけよ」
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ITM
Member #798
November 2000
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Posted on 08/14/2004 6:05 AM   View Profile

Same as BAF's one

spellcaster
Member #1,493
September 2001
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Posted on 08/14/2004 9:13 AM   View Profile

You have to link against the static version of allegro :)

Quote:

btw-- it segfaults here on the bitblt. i wanted to beat up my desktop too.

Download the precompiled version if you have problems compiling it.

--
There are no stupid questions, but there are a lot of inquisitive idiots.

ReyBrujo
Moderator
January 2001
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Posted on 08/14/2004 12:31 PM   View Profile

gcc agression.c -o agression -lalleg_s -mwindows for statically linked, yep.

--
RB
光子「あたしただ…奪う側に回ろうと思っただけよ」
Mitsuko's last words, Battle Royale

BAF
Member #2,981
December 2002
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Posted on 08/14/2004 1:18 PM   View Profile

plus all the libs it needs. I just removed the static link and compiled with -lalleg. The precompiled one crashes too. (windows xp)

BAF.zone | SantaHack!

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