C / C++ / MFC

SimplCodr22-Jun-07 12:46

SimplCodr

22-Jun-07 12:46

Thanks for your input,

I tried to use this without susccess. It seems very complicated to me.

I created the HANDLE object.
HANDLE hFile;

I then created a pointer to the string containing the path.

const char fPath = "C:\\Myfile";

I created the handle as follows;

hFile = FindFirstFile(hFile, NULL);

This built fine but always return INVALID_HANDLE_VALUE even though the file was there.

I am sure I dont have this right. Notice I did not try to use the second perameter, which might also be a problem. Sure seems like alot of code just to see if a file's there or not.

Hamid_RT22-Jun-07 22:29

Hamid_RT

22-Jun-07 22:29

Try to this code and see result

HANDLE hFile;
WIN32_FIND_DATA win32;
hFile = FindFirstFile("c:\\1234.txt", &win32);
//if you have this file then win32 is fills with detaily of file and hFile is return a valid handle else you dont have this file.

WhiteSky

SimplCodr27-Jun-07 7:20

SimplCodr

27-Jun-07 7:20

Thanks,

That is alot easier than what I was trying to do with it. Thanks for your help.

Terry

Hamid_RT27-Jun-07 7:42

Hamid_RT

27-Jun-07 7:42

You're welcome. Smile | :)

I think best thing for me is when I can solve a problem for people.

WhiteSky

video capture, edit, playback

SimplCodr22-Jun-07 13:01

SimplCodr

22-Jun-07 13:01

I belive the suggestion David had was easier than this but, here is another way that seems pretty simple Smile | :)

.

GetFileAttributes();

If it fails it returns a DWORD 0xFFFFFFFF.

moonraker92821-Jun-07 9:50

moonraker928

21-Jun-07 9:50

hi.

i am creating an application that needs to capture a video of a computer simulation on the monitor in real-time. then based on some metrics and other data, i need to edit the video by adding lines, shapes, and words inside the video. then i need to playback the video with the edited components embedded.

what are the best free APIs out there that allow me to accomplish the task above??

thanks!

--
dg

jk chan21-Jun-07 22:24

jk chan

21-Jun-07 22:24

How you are going to capture the video ?
IF it the videoformat is raw avi , u can write some directshow filters to add ur on lines or shpaes to the frame. If it is compressed one, i think it may not possible in real time without some special hardware support.

If u can Dream... U can do it

moonraker92822-Jun-07 8:37

moonraker928

22-Jun-07 8:37

Yes I was reading about DirectShow. So just to clarify, DirectShow will enable me to capture the video, edit the video by adding my shapes, lines, and text, and playback the video with the new stuff embedded? The videoformat, to avoid any more complexity, is probably going to be raw AVI.

In that case, DirectShow is the plan of action? Are there any alternatives - just curious?

--
dg

jk chan23-Jun-07 20:58

jk chan

23-Jun-07 20:58

I don't know how to make video from screen. If it simple api , you can grab images from screen ( using win32funcions ) and you can create aVI.

IF it is mpeg or any compressed formats , it is more difficult to do it inreal time (also depends on the frame rate you want )

After saving the file as a avi. you can use directshow to to read that file. ( If it is avi , I think no need for directshow.. We can just grab every frame.. ). But directshow is more well organized.. there are class for reading from file , stream etc.

Adding lines or text is not much difficult . it is just bitmap manipulation.

Hopes this will give you some small idea. Smile | :)

If u can Dream... U can do it

moonraker92822-Jun-07 11:36

moonraker928

22-Jun-07 11:36

One other thing I noticed in msdn when I was reading about directshow was that it only supports video capture from a hardware device like tv tuner cards or cameras...

the video i want to capture will be running on a C++ application on my computer screen. in fact, i want to incorporate the video capture, edit, and playback features within that same application so it can be more integrated.

if this is the case, can directshow do what i want? if not, what are the alternatives??

--
dg

WIll VC++ run on Linux ?

Ylno21-Jun-07 9:42

Ylno

21-Jun-07 9:42

Hello,

Possibly a stupid question.

Will C++ code run on linux? or does it target the .NET?

If the answer to the first question is no then what would be the best
genral purpose cross platform language to learn ?

Thanks

simoncoul21-Jun-07 9:58

21-Jun-07 9:58

C++ can run on linux, but all the MFC and .NET stuff doesn't. Check out Mono, it's a project that will allow .net stuff to run on linux when written in C#.

David Crow21-Jun-07 10:12

David Crow

21-Jun-07 10:12

Ylno wrote:
Will C++ code run on linux?

This question makes no sense. Once (c++) code is compiled, the language used is no longer relevant. It's "machine language" at that point.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Ylno21-Jun-07 10:29

Ylno

21-Jun-07 10:29

Sorry if the question makes no sense. That was obviously my fault, i won't be doing that again. Next time i'll be in a position to talk down to a newbie on this subject.

So next stupid question: if the language is no longer relevant then is the
machine language of linux compatible with windows?
I wouldn't have thought so but you can suprise me.

Basically i'm after a language that i'll be able to use cross-platform ...

David Crow21-Jun-07 10:33

David Crow

21-Jun-07 10:33

Ylno wrote:
...is the
machine language of linux compatible with windows?

No, they use different instruction sets. High-level code can be ported from one platform to the other, though. You'll just need a compiler on each to create the machine code.

See here for more.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Ylno21-Jun-07 10:38

Ylno

21-Jun-07 10:38

Thanks Dave,

You've cleared things up.

markkuk21-Jun-07 21:36

markkuk

21-Jun-07 21:36

Ylno wrote:
is the
machine language of linux compatible with windows?

Linux (or Windows) doesn't have a machine language, machine language is a feature of the processor chip and it's independent of any OS you may be running.

Ylno wrote:
Basically i'm after a language that i'll be able to use cross-platform

C, C++, Java, Python, Ruby, Perl, ...

Problem with painting and global varibles

anzhiguoccc21-Jun-07 17:50

anzhiguoccc

21-Jun-07 17:50

good answer! Laugh | :laugh:

simoncoul21-Jun-07 9:33

21-Jun-07 9:33

Hello, I'm having a bit of trouble and was hoping you guys would be able to help me out. Right now I have a function that produces a 2 arrays with number used from graphing. In the OnPaint part for the dialog box I simply used the MoveTo and LineTo to graph. In order for both functions to get at those arrays I put at the top of the code(like how I would with a global varible in C). But now that program will crash when I run that function twice because of the painting. Any ideas of how to solve this, am I declaring the arrays in the wrong place?

Thanks

Mark Salsbery21-Jun-07 9:39

21-Jun-07 9:39

Are the arrays initialized at the time the first WM_PAINT message is received?

What does the code look like where the crash occurs?

Mark

"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder

simoncoul21-Jun-07 9:56

21-Jun-07 9:56

No they are initilized after the WM_PAINT. The code crashes when I access the arrays for the second time to paint, If I comment out the paint code the program will just fine. The code looks like this where is crashes, where x_prime2 and Ey_x2 are the arrays

for(int i=0; i<=999; i++){	
	x = (30+scale2*x_prime2[i]);
	y = (scale1*Ey_x2[i].Real());
	if(i == 0){		
		dc.MoveTo(int(x+min_1*(-1)*scale2), int(y*(-1)+640));
	}
	else{	
		dc.LineTo(int(x+min_1*(-1)*scale2), int(y*(-1)+640));
	}
}

And I initilize them like this

#include "stdafx.h"
#include <math.h>
#include "complex.h"
#include <complex>

int Nglobal;
int *layerglobal = new int [100];
double *thickglobal = new double [100];
Complex *Ey_z_C2=new Complex [1000];//Electrical field in the ridge area in growth direction
Complex *Ey_z_L2=new Complex [1000];//Electrical field in the shoulder area in the growth direction
Complex *Ey_x2= new Complex [1000]; // Electrical field in the transverse direction
Complex *z_prime2=new Complex [1000];			
double *x_prime2=new double [1000];

Mark Salsbery21-Jun-07 10:24

21-Jun-07 10:24

I can't see anything off hand....are you getting a floating point exception?
How is it crashing?

"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder

Mark Salsbery21-Jun-07 10:26

21-Jun-07 10:26

Also, you ARE putting valid values into the arrays before calculations are done on the values,
right?

"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder

simoncoul22-Jun-07 2:40

22-Jun-07 2:40

Yes the values that are being put in are valid, I do not know what a floating point exception is though. The program runs just fine in debug, which is driving me crazy I just can't get the release version to work. Do you think it could have something to do with the compiler options? Is there a way I can paint directly from the function instead of using the OnPaint function?

Thank you very much!

Mark Salsbery22-Jun-07 4:35