C / C++ / MFC

Shunya29-Jun-10 23:32

29-Jun-10 23:32

oh dear,
what i meant was I want a program which takes a group of
input simple polygons and merges them with the 2nd group
of simple polygons.
I have located 2 libraries (both use vatti's) algorithm
for clipping.
My polygons are without hoes,not self intersecting and only graze at edges(if at all).
I want to merge them to get the outer contour of the final merged polygon.
I presume that would be easier to do then the clip in the 2 heavy libraries.

Code-o-mat30-Jun-10 0:37

Code-o-mat

30-Jun-10 0:37

YOu said you located 2 libraries that can "merge" 2 polygons, as i understood, i thought your problem was how you would merge more then two polygons. So actually what you want has nothing to do with the libraries because you don't want to use them but instead you want to do the task without the help of these, right? Well, if you are doing this under windows you could try creating regions from your polygons and merge them (windows can do this for you), how you get the points back from the resultiong region i don't know yet.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> "It doesn't work, fix it" does not qualify as a bug report. <
> Amazing what new features none of the programmers working on the project ever heard of you can learn about when reading what the marketing guys wrote about it. <

Shunya30-Jun-10 1:17

30-Jun-10 1:17

yes, i want to merge the regions and just get the outer contour.
As simple as that and I have to use clipper?.(it is in borland delphi/c++)

Code-o-mat30-Jun-10 1:22

Code-o-mat

30-Jun-10 1:22

I doubt Clipper is the only language you could implement this in.

Shunya30-Jun-10 1:39

30-Jun-10 1:39

no it is in delphi/c++ and gpc is in c++.I dont a demo program to use
the libraries under vs2010..that is the problem.both use a algorithm
called vattis algorithm in computational Geometry.
in vs2010 /c++(unmanaged) i dont know how to do graphics .

Code-o-mat30-Jun-10 2:12

Code-o-mat

30-Jun-10 2:12

So let me get this straight:
1. one of the libraries you could use is written in C++
2. the second one you could use is written in pure, standard C++
3. you have sources, so not lib files
4. you want to work in VC++ with VS2010, use one of these libraries in it and display graphical representations of your polygons but you don't know how to:
-use any of the libraries in VC++
-do graphics in VC++

If i am correct then i believe you should first learn some basic VC++/Windows programming before getting to the actual implementation of this polygon thing. If one of your libraries is written in standard C++, you probably whould be able to build it with VC++ too.

Shunya30-Jun-10 2:53

Control move from original position

30-Jun-10 2:53

yes,you got it right.I also know how to do some vc++(the old c++ not the new
one with lambda,..).I know vb.net ok and also c++.
I have asked a friend to help me in command line and probably when i show him my face next we will have a c++ program which
readpolygons,readpoygons,
perform union,
write result polygons

no graphics....so sad...

ps:i have got 1 more library, in c of the previous decades.

MsmVc29-Jun-10 0:58

MsmVc

29-Jun-10 0:58

Hi All

I am facing very fracturing problem.My application some control move from original position and some control hide.i use Static,Edit Box,List Box,List Control,Picture control and Spin Control.

I use OnEraseBkgnd and OnCtlColor function for background color and control color.Code is here

HBRUSH CTestDlg::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
	HBRUSH hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);

	if((pWnd->GetDlgCtrlID() == IDC_CHECK_REAL) || (pWnd->GetDlgCtrlID() == IDC_STATIC_REAL))
	{
		hbr = CreateSolidBrush(RGB(250, 252 , 254));
		pDC->SetBkColor(RGB(250,252,254));
		pDC->SetTextColor(RGB(0,0,0));
		pDC->SetBkMode(OPAQUE);
	
	}
	if((pWnd->GetDlgCtrlID() == IDC_EDIT_MAXPATH))
	{
		hbr = CreateSolidBrush(RGB(255, 255 ,255));
		pDC->SetBkColor(RGB(255, 255 , 255));
		pDC->SetTextColor(RGB(0,0,0));
		pDC->SetBkMode(OPAQUE);
	
	}
}


BOOL CtESTDlg::OnEraseBkgnd(CDC* pDC)
{

	CRect rect;
	GetClientRect(&rect);	
	pDC->FillSolidRect(rect,RGB(250,252,254));	
	return TRUE;


}

How to set the value in ComboBox

raju_shiva29-Jun-10 0:55

raju_shiva

29-Jun-10 0:55

Hi sir.
When i type any character in the CombBox.I am sorting and displaying the results in dropdown.
But the first string which comes in DropDown is being set in ComboBox.

For Ex: If i have some strings in CComboBox : 1)"Pas",2)"Pad"
When i type P in Combo the same "P" character must be set to the ComboBox not "Pas".

Any idea will be thankful

Thanks
Raj

Re: How to set the value in ComboBox

MsmVc29-Jun-10 1:03

MsmVc

29-Jun-10 1:03

you can not directly enter values in comboBox.
You can use like this

 CComboBox* test;

for (int i=0;i< test->GetCount();i++)
{
   test->SetItemData(i, i);
}

problem with image scaning & displaing . win32 StretchDIBits ()

ashish8patil29-Jun-10 0:25

ashish8patil

29-Jun-10 0:25

Hello All,

General Idea:- I am developing application win32 cleint server type (It is like desktop monitoring ).

On server side I am takeing screen shot. & sending it to client side.

On server side I have function code like
--------------------------------------------
|
|
|

<pre><pre>hdc1 = GetDC(NULL);
hdc2 = CreateCompatibleDC(hdc1);
GetWindowRect(GetDesktopWindow(), &rc);
w = rc.right-rc.left;
h = rc.bottom-rc.top;
bmih.biSize = sizeof(BITMAPINFOHEADER);
bmih.biWidth = w;
bmih.biHeight = h;
bmih.biPlanes = 1;
bmih.biBitCount = 24;
bmih.biCompression = BI_RGB;
bmih.biSizeImage = ((((bmih.biWidth * bmih.biBitCount) + 31) & ~31) >> 3) * bmih.biHeight;
bi.bmiHeader = bmih;
aBmp = CreateDIBSection(hdc1, &bi ,DIB_RGB_COLORS, (void**)&dibvalues, NULL, NULL);
OldObj = SelectObject(hdc2, aBmp);
BitBlt(hdc2, 0, 0, w, h, hdc1, 0, 0, SRCCOPY);</pre>

//////////////////////////////////////////////////////////////</pre>

I have class like

<pre>class DesktopScreen{
public:
BITMAPINFOHEADER bmih ;
BITMAPINFO bi; unsigned char dibvalues[lenght]; };</pre>------------------------------------------------------------------

using above code I am filling Object of this class & sending it to other side

in binary formate (byte).

On Client side deserializing is also OK (I check all value at time of debuging )

<pre>Now at time WM_Paint:
hDC = BeginPaint(hWnd, &Ps);

i= StretchDIBits(hDC, // destination rectangle 0, 0, GetSystemMetrics(SM_CXSCREEN), GetSystemMetrics(SM_CYSCREEN), // source rectangle 0, 0,desktopObj.bmih.biWidth , desktopObj.bmih.biHeight, desktopObj.dibvalues, &desktopObj.bi, DIB_RGB_COLORS, SRCCOPY);
//////////////////////////////////////////////////////////////////////////</pre>

StretchDIBits is returning 0 .

Application run properlly but image is not displying.

also if i call StretchDIBits on server side passing same info to that function.I mages is displaying.

Can you please tell me what should be the problem.

( sorry for posting code ,but I think it is necessary to get my Question to you )

Thanks ,
Ashish.

Ownerdarw Combobox

AbhiHcl28-Jun-10 23:33

AbhiHcl

28-Jun-10 23:33

Hi I want to create ownerdraw combobox. But whenever I m calling the create function its giving assertion error. Can anybody tell me why its happeing.

here is code :

void CTxComboBoxCtrl::CreateCustomComboBox(CRect rect, CWnd* pWnd, UINT nID)
{
this->Create(WS_CHILD|WS_VISIBLE|WS_BORDER|WS_HSCROLL|WS_VSCROLL|CBS_HASSTRINGS |CBS_DROPDOWNLIST |CBS_OWNERDRAWVARIABLE ,rect,pWnd,nID);

}

CTxComboBoxCtrl id derived from CComboBox class

Thanks..

Nibu babu thomas28-Jun-10 23:41

Nibu babu thomas

28-Jun-10 23:41

You should override DrawItem function.

Nibu babu thomas
Microsoft MVP for VC++

Code must be written to be read, not by the compiler, but by another human being.

Programming Blog: http://nibuthomas.wordpress.com

AbhiHcl28-Jun-10 23:47

AbhiHcl

28-Jun-10 23:47

ys I m overriding the ownerdraw function. but its giving arrestion error on the beginging its self when I m calling create function from oninitdialog funuction of the dailog.

Nibu babu thomas28-Jun-10 23:48

Nibu babu thomas

28-Jun-10 23:48

Please show us the ASSERT code.

Nibu babu thomas
Microsoft MVP for VC++

Code must be written to be read, not by the compiler, but by another human being.

Programming Blog: http://nibuthomas.wordpress.com

AbhiHcl28-Jun-10 23:54

AbhiHcl

28-Jun-10 23:54

In this line its giving assertion :

void CComboBox::MeasureItem(LPMEASUREITEMSTRUCT)
{ ASSERT(FALSE); }

Aescleal28-Jun-10 23:59

Aescleal

28-Jun-10 23:59

This tells you exactly what's wrong - you haven't overidden MeasureItem in your derived class so MFC's telling you to go and do it rather than letting your code crash in a novel and interesting way later.

Cheers,

Ash

Nibu babu thomas29-Jun-10 2:01

Nibu babu thomas

29-Jun-10 2:01

Since you've given CBS_OWNERDRAWVARIABLE as combo style, you need override MeasureItem.

Nibu babu thomas
Microsoft MVP for VC++

Code must be written to be read, not by the compiler, but by another human being.

Programming Blog: http://nibuthomas.wordpress.com

swap different sized string

Aescleal28-Jun-10 23:58

Aescleal

28-Jun-10 23:58

Quick hint: When the assertion fires you usually get the option to go to the line that triggered the assertion. Use a debugger when the assertion fires, have a dig around and try and relate the state of the code where you are to the parameters you passed into the Create function.

It could be that you're trying to create a window with the same ID to one already in existence in a dialogue box (in which case you might need to subclass an existing control instead) or the style parameters don't work for this class. The trouble is we have no idea why/where this is happening as you can go straight to the code causing the problem and get an idea without much effort.

Cheers,

Ash

rupeshkp72828-Jun-10 22:05

rupeshkp728

28-Jun-10 22:05

how can I write a function to swap to different sized string?

Cedric Moonen28-Jun-10 22:14

Cedric Moonen

28-Jun-10 22:14

What do you mean exactly Confused | :confused:

? Could you provide an example describing what you are looking for ?

Cédric Moonen
Software developer

Charting control [v3.0]
OpenGL game tutorial in C++

rupeshkp72828-Jun-10 22:26

rupeshkp728

28-Jun-10 22:26

Like in main function I will read two string from user. I will store the string either in array of fixed size or in a pointer or simply say in the main() there are two strings:
char *c = "MSN"
char *d = "YAHOO"

I have to pass these two string in a function say swapstrings() and swap these two variables

Aescleal28-Jun-10 23:51

Aescleal

28-Jun-10 23:51

You might feel this is being overly pedantic... trust me it's not. You don't store strings in pointers - all you store in pointers are addresses. It just so happens that the character pointers you're talking about point to the first character of the block of memory you've got the characters representing the string in.

If you understand that then it should be fairly easy to work out how to switch the pointers around and get the result you're after.

Cheers,

Ash

Adam Roderick J28-Jun-10 22:14

Adam Roderick J

28-Jun-10 22:14

I cannot understand what is the difficulty in writing that?
can you clarify your question.

Величие не Бога может быть недооценена.