C / C++ / MFC Discussion Boards

Why do the WndProc get a "&MSG" , instead four parameters?

bloggs197412-May-04 4:31

bloggs1974

12-May-04 4:31

I mean that WndProc(&MSG) may be a better choice, but the win system use WndProc(hwnd,msg,wParam,LParam), why?

There are so many API functions, where can I find a list of the most important function?

bloggs197412-May-04 3:10

bloggs1974

12-May-04 3:10

Is there anyone make a catalog of the essential APIs which a beginner should know?

I need Help

Guiro11-May-04 9:52

Guiro

11-May-04 9:52

I need to write two programs for my algo class...
1) I have to compare the insertionSort, MergeSort and QuickSort on an array of million chars using rand() and clock()...
2) Compare the number of leaves of a binary tree (I have to think recursively)

If anyone can help please do...it has to be done in C...Please anyone help...

TS

Re: I need Help

David Crow11-May-04 10:18

David Crow

11-May-04 10:18

"Help me" is not the same as "do it for me." Show us the code that is giving you trouble, and you're bound to get help.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: I need Help

Christian Graus11-May-04 11:19

Christian Graus

11-May-04 11:19

I'm happy to do this for you. You can use Paypal to pay my fees. I hope your daddy is rich. If you skip out on this lesson, you'll probably need my help for the next one, and the one after that, etc. I can retire and just make a living doing easy programming assignments for rich people too lazy to learn for themselves.

Or you could give it a go and post your code here when you get stuck. Then I'll help for free.

Christian

I have drunk the cool-aid and found it wan and bitter. - Chris Maunder

Re: I need Help

Maxwell Chen11-May-04 16:59

Maxwell Chen

11-May-04 16:59

Guiro wrote:
1) I have to compare the insertionSort, MergeSort and QuickSort on an array of million chars using rand() and clock()...
2) Compare the number of leaves of a binary tree (I have to think recursively)

Since you have written those many programming jargons (like Merge Sort, rand(), recursively, ...), you know well about programming and you can do it yourself!

Maxwell Chen

AC-3

Alexander ^M.,11-May-04 8:31

Alexander ^M.,

11-May-04 8:31

Hello everyone, I'm looking for information about the AC-3 (also called a52) algorithm.
I've already found an implementation, but it is slow and a very "simple" encoder, not much worth to gather information from it. I also had a look at the standard definition of ATSC, but there are still many unclear things. Does anyone know a good source of information or source codes (no matter which language)?

thx for your answers
Alex

Don't try it, just do it! Wink | ;-)

Re: AC-3

Maxwell Chen11-May-04 17:06

Maxwell Chen

11-May-04 17:06

Making AC-3 an Optimal Algorithm[^]

Maxwell Chen

Petri nets

moscow_bear11-May-04 8:00

moscow_bear

11-May-04 8:00

I need a library that implements a behaviour of Petri Nets. I know it wouldn't be too hard to implement the functionality myself, but establishing the link with Petri nets is just a secondary (if not tertiary) goal of my course project and a have not enough time to invent a bicycle.

Re: Petri nets

igor196012-May-04 9:32

igor1960

12-May-04 9:32

What about Maria:
http://www.tcs.hut.fi/Software/maria/

"...Ability to type is not enough to become a Programmer. Unless you type in VB. But then again you have to type really fast..."
Me

Mouse-Screen Edge Detection

User 1278211-May-04 7:48

User 12782

11-May-04 7:48

I would like to detect when the mouse is on any of the edges of the screen and then the user moves the mouse in such a manner that the mouse would go off-screen if it was allowed to do so. I've tried using WM_MOUSEMOVE messages, but the lParam/POINT structure never has negative values. Another option I could see is storing the mouse position from the previous mousemove message and then calculating a slope and whatnot and see if its in certain bounds to consider it to be going off-screen. This is hardly a ideal approach and wouldn't work if the mouse was already near the edge of the screen. I'm sure there is a better way, but I don't have any clue what it could be. Any suggestions?

Thanks,
Aaron

modified 12-Jul-20 21:01pm.

Re: Mouse-Screen Edge Detection

John R. Shaw11-May-04 10:12

John R. Shaw

11-May-04 10:12

The best I can see is to detect when it is on the edge of the screen. One of the things you may have notice with programs like the Taskbar is when they hide, they always leave one of the edges showing (at the edge of the screen)so than can detect when mouse (hot spot) passes over it.

INTP

Re: Mouse-Screen Edge Detection

User 1278211-May-04 14:00

User 12782

11-May-04 14:00

Thanks, that's always an option, and it looks like that's what I'll go with. A couple pixels probably isn't going to make much of a difference anyway. The reason I ask is I've seen apps, like mouse wrappers, that seem to work the way I want.

Thanks,
Aaron

modified 12-Jul-20 21:01pm.

linking error messages

Anonymous11-May-04 7:13

Anonymous

11-May-04 7:13

What would be the reason for getting following linking error?

a) LNK2019: unresolved external symbol _WinMain@16 referenced in function _WinMainCRTStartup
b)LNK1120: 1 unresolved externals

Re: linking error messages

David Crow11-May-04 8:32

David Crow

11-May-04 8:32

LNK2019 is a .NET thing, but you'll also see it as LNK2001 on other platforms. See if this helps.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: linking error messages

Anonymous11-May-04 9:16

Anonymous

11-May-04 9:16

Thank you very much it is really helpful and now I got no more linking error.
Thank you again.

Re: linking error messages

Anonymous11-May-04 18:32

Anonymous

11-May-04 18:32

Sounds like you setup the project to build a Windows application, when you've probably coded for a console application. To fix the unresolved external symbol_WinMain@16 referenced in function _WinMainCRTStartup go into your project settings and change the "/subsystem:windows" project setting to "/subsystem:console". That should clear up the error. Hope this helps.

Regards,

TIF file display

LasVegasGuy11-May-04 6:58

LasVegasGuy

11-May-04 6:58

I need to display a tif file as a thumbnail on a dialog box. Is there any Activex control available that I can use?
thanks

Man Learns from History that he never learns from History

Re: TIF file display

Anthony_Yio12-May-04 2:21

Anthony_Yio

12-May-04 2:21

Check out

http://www.codeproject.com/vcpp/gdiplus/GdiPThumbnailsViewer.asp

But it is in GDI+ and MFC though

Sonork 100.41263:Anthony_Yio

Life is about experiencing ...

System::String _gc* to char *

deniz79s11-May-04 6:56

deniz79s

11-May-04 6:56

I can't achieve this process in .Net Visual C++.

I use below code and the interpreter doesn't give any error at compile time but an error is occours at run time ("object referance not set to an object instance")

char *dosya;
String *dizi;

dizi=textBox1->Text;
dosya=new char(512);

dosya=reinterpret_cast<char *="">(dizi->ToCharArray());

also I used below code and the compiler gave an error at run time ("index was outside of range" like this I can't remember completly)

dosya=reinterpret_cast<char *="">(dizi->get_Chars(dizi->get_Lenght()));

for summary I can't get the characters from a System::String class to a char pointer. (instead of char to use wchar_t variable didn't solve the problem

Re: System::String _gc* to char *

HENDRIK R11-May-04 7:22

HENDRIK R

11-May-04 7:22

a look at msdn brings the following solution:

using namespace System::Runtime::InteropServices;

const char* str = (const char*)<br />
   (Marshal::StringToHGlobalAnsi(managedString)).ToPointer();<br />
// use str as you wish or copy it elsewhere<br />
// free string<br />
Marshal::FreeHGlobal(IntPtr((void*)str));

We are men. We are different. We have only one word for soap. We do not own candles. We have never seen anything of any value in a craft shop. We do not own magazines full of photographs of celebrities with their clothes on. - Steve

Connected Printers.

Prakash Nadar11-May-04 6:23

Prakash Nadar

11-May-04 6:23