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Re: In MFC, when opening a file or creating a file, is WM_PAINT generated?

Richard Andrew x644-Dec-13 16:02

Richard Andrew x64

4-Dec-13 16:02

My best guess is that the framework is drawing the view because a new document has just been loaded into it.

What is it you are trying to achieve?

Probably the only thing you can change is how the message is handled, not that the message is received.

Override the CView's OnWndMsg function to alter how any message is handled.

The difficult we do right away...
...the impossible takes slightly longer.

Re: In MFC, when opening a file or creating a file, is WM_PAINT generated?

Richard MacCutchan4-Dec-13 22:07

Richard MacCutchan

4-Dec-13 22:07

The CDocument class calls UpdateAllViews which in turn sends a WM_PAINT message to each view to redraw itself. In some cases you need to make that call in your code to ensure your views are current. You should check the documentation[^] for further details about its behaviour.

Veni, vidi, abiit domum

Re: In MFC, when opening a file or creating a file, is WM_PAINT generated?

rainclear5-Dec-13 4:09

5-Dec-13 4:09

I set a break point in CDocument::UpdateAllViews(). It seems that this function is not called when opening or creating a file.

Re: In MFC, when opening a file or creating a file, is WM_PAINT generated?

rainclear5-Dec-13 5:20

5-Dec-13 5:20

I found the reason. When either creating or opening a file, CSingleDocTemplate::OpenDocumentFile() is called. Then it calls InitialUpdateFrame(). Then InitialUpdateFrame() calls CView::OnUpdate() and CView::OnUpdate() calls Invalidate(TRUE).

Re: In MFC, when opening a file or creating a file, is WM_PAINT generated?

xspace_time9-Dec-13 14:42

9-Dec-13 14:42

I think you can find some documents from google about WM_PAINT, it is called by windows message

Efficient and Faster way to do 2x2 binning of a matrix

Kiran Satish4-Dec-13 7:11

4-Dec-13 7:11

Hello,

I am trying to implement a faster way to do 2x2 binning of a 1024x1024 matrix of byte (char) databyte in MFC. The end result will be in a 512x512 matrix. I can do this using two for loops, but I am looking for a faster and efficient way to implement this.

Any suggestions?

thanks

PKNT

Re: Efficient and Faster way to do 2x2 binning of a matrix

jschell4-Dec-13 11:24

4-Dec-13 11:24

Presumably you are using a byte lookup rather than a mask operation.

You can try indexing from end to end and then using two indexes one for the first row (say position X) and then one one for the second (X+1024). However that would then require an if test each time to skip the second row once you reached 1024.

c++ upd brodcast client

arishri3-Dec-13 2:57

3-Dec-13 2:57

hi I'm programming a c++ client to receive packets from a server (UDP broadcast). This is a hardware switch (One direction only) system so I have no information regarding the senders address or any other info. It all compiles and binds OK but no packets received.

C#

WSAStartup(0x0101, &_wsaData);
memset((char *)&_sockaddr, 0, sizeof(_sockaddr));
_sockaddr.sin_addr.s_addr   = _nAdapterIp;
_sockaddr.sin_family        = _nadressFam;
_sockaddr.sin_port      = _usPort; //Gave it a try with (0) - also not working
_socket = socket(_nadressFam, SOCK_DGRAM, 0); //Gave it a try with (17) - UDP for the 3 rd parameter - not working
char broadcast='1';
setsockopt(_socket, SOL_SOCKET, SO_BROADCAST, &broadcast ,sizeof(broadcast));
bind(_socket, (sockaddr*) & _sockaddr, sizeof (_sockaddr));
char* recvbuf = new char[_nPacketSize + 1];
int nSize = recv(_socket, recvbuf, _nPacketSize + 1, 0);

Any ideas?  Thanks,

Re: c++ upd brodcast client

jeron13-Dec-13 3:34

3-Dec-13 3:34

One important thing to do is look at the return codes for the methods that you are calling and your socket constructor, most times they will give you a clue about what is wrong. Also, what are values _nAdapterIp, _nadressFam, and _usPort? Could you be suffering from endian type issues?

Re: c++ upd brodcast client

arishri3-Dec-13 3:40

3-Dec-13 3:40

sorry abut that, I shorten it so the code will be clear....
The actual code has the tests:

C#

if (WSAStartup(0x0101, &_wsaData) != 0)
    {
        fprintf(stderr, "Could not open Windows connection.\n");
        exit(0);
    }

C#

char broadcast= (char)1;

    if (setsockopt(_socket, SOL_SOCKET, SO_BROADCAST, &broadcast ,sizeof(broadcast)) != 0)
    {
        fprintf(stderr, "Could not set socket options.\n");
        WSACleanup();
        exit(0);
    }

etc....

Re: c++ upd brodcast client

jeron13-Dec-13 4:01

3-Dec-13 4:01

arishri wrote:
_socket = socket(_nadressFam, SOCK_DGRAM, 0); //Gave it a try with (17) - UDP for the 3 rd parameter - not working

How could you tell it wasn't working? I assume IPPROTO_UDP equates to '17'. When your application is running, and you go to DOS prompt and do a "netstat -a" do you see your socket with the proper port listed?

Re: c++ upd brodcast client

arishri3-Dec-13 4:11

3-Dec-13 4:11

C#

_socket = socket(_nadressFam, SOCK_DGRAM, 17);
    _socket1 = socket(_nadressFam, SOCK_DGRAM, 17);

    if ((_socket == INVALID_SOCKET) || (_socket1 == INVALID_SOCKET))
    {
        fprintf(stderr, "Could not create socket.\n");
        WSACleanup();
        exit(0);
    }

Re: c++ upd brodcast client

jeron13-Dec-13 4:21

3-Dec-13 4:21

Stick with one socket for now. If it still fails, call WSAGetLastError() and see what the error is.

Re: c++ upd brodcast client

arishri3-Dec-13 4:13

3-Dec-13 4:13

int nSize = recv(_socket, recvbuf,_nPacketSize + 1, 0);

Get no packages here....

Re: c++ upd brodcast client

jeron13-Dec-13 4:29

3-Dec-13 4:29

I couldn't be firewall related, could it?

Re: c++ upd brodcast client

Member 104421753-Dec-13 21:25

Member 10442175

3-Dec-13 21:25

<pre Lang="turbo c">
#include<studio.m>
main()
{
char m;
int p;
float n;
scanf ("%s%d%f",&m,&p,&n);
} </pre>

pointer to pointer

messages2-Dec-13 7:13

2-Dec-13 7:13

Hi everyone
The output of this code is 10,
I want to know why **q prints 10?
int x,*p,**q;
x=10;
p=&x
q=&p;
cout<<**q;

Re: pointer to pointer

Joe Woodbury2-Dec-13 8:56

2-Dec-13 8:56

p points to x, which is assigned 10.
q points to p, which points to x.

*q returns p. Now you need to dereference that result to get to x. With parenthesis, you get: *(*q) == *p

[SOLVED] Capture CAM using Media Foundation

Django_Untaken2-Dec-13 5:27

2-Dec-13 5:27

Hello sound and video gurus. I am trying to capture my integrated web cam using Media Foundation APIs. I could not figure out the following couple of points.

1 - Difference between RAW video and uncompressed video
2 - Video format for RAW video (like PCM for RAW audio, MFVideoFormat_Base perhaps?)

I am using the following code to capture and store data onto my hard disk (a lot of code is ommited for clarity). I am saving on 100 samples but it stores 267+ hours of data. Here it is

C++

BOOL CMyClass::StartRecording()
{
  HRESULT hResult;
  dwActualStreamIndex = 0;

  m_bFirstSample = TRUE;
  m_llBaseTime = 0, m_llTimeStamp = 0;
	
  IMFSample* pSample = NULL;
  IMFMediaBuffer* pMediaBuffer = NULL;
  BYTE* pData = NULL;

  BOOL bResult = InitCamera();  // this code is ommited. just assume it is correct
  if(!bResult) return FALSE;

  hResult = m_pReader->ReadSample((DWORD)MF_SOURCE_READER_FIRST_VIDEO_STREAM, 0, &dwActualStreamIndex, &dwStreamsFlags, &m_llTimeStamp, &pSample);
  if(FAILED(hResult)) return FALSE;

  hResult = m_pReader->ReadSample((DWORD)MF_SOURCE_READER_FIRST_VIDEO_STREAM, 0, &dwActualStreamIndex, &dwStreamsFlags, &m_llTimeStamp, &pSample);
  if(FAILED(hResult)) return FALSE;

  // 100 samples contain 267+ hours of data ? something wrong with this loop
  for (DWORD i = 0; i < 100; ++i)
  {
	hResult = m_pWriter->WriteSample(0, pSample);
	if(FAILED(hResult)) return FALSE;

	unsigned int c=0;
	hResult=pSample->GetBufferCount((DWORD*)&c);
	if(FAILED(hResult))MessageBox(NULL, "err","get buffer count", MB_OK);
 
	IMFMediaBuffer* buffer=NULL;
	hResult=pSample->GetBufferByIndex(0,&buffer);
	if(FAILED(hResult))MessageBox(NULL, "err","GetBufferByIndex", MB_OK);
 
	unsigned int sz=0;
	hResult=buffer->GetCurrentLength((DWORD*)&sz);
	if(FAILED(hResult))MessageBox(NULL, "err","GetCurrentLength", MB_OK);
 
	unsigned char* data=NULL;
	unsigned int validSize=0;
	hResult=buffer->Lock((BYTE**)&data,NULL,(DWORD*)&validSize);
	if(FAILED(hResult))MessageBox(NULL, "err","Lock", MB_OK);
 
	hResult=buffer->Unlock();
	if(FAILED(hResult))MessageBox(NULL, "err","Unlock", MB_OK);

	hResult = m_pReader->ReadSample((DWORD)MF_SOURCE_READER_FIRST_VIDEO_STREAM, 0, &dwActualStreamIndex, &dwStreamsFlags, &m_llTimeStamp, &pSample);
	if(FAILED(hResult)) return FALSE;
  }

	return TRUE;	
}

Thanks for any pointers.

modified 9-Dec-13 7:57am.

How to add the number to the shortcut in the desktop of the application.

yu-jian2-Dec-13 3:32

2-Dec-13 3:32

I find some application can show a number in the shutcut in the desktop , but I cannot find which windows api can do it. Is there anyone know it?

Re: How to add the number to the shortcut in the desktop of the application.

Richard MacCutchan2-Dec-13 5:14

Richard MacCutchan

2-Dec-13 5:14

What do you mean by "show a number in the shutcut in the desktop"?

Veni, vidi, abiit domum

Re: How to add the number to the shortcut in the desktop of the application.

jeron12-Dec-13 5:40

2-Dec-13 5:40

Do you mean something like "Microsoft Word (2)"?

Re: How to add the number to the shortcut in the desktop of the application.

yu-jian2-Dec-13 5:55

2-Dec-13 5:55

No, this is changed the shortcut name. I means that display a number in the icon of the shortcut.

Re: How to add the number to the shortcut in the desktop of the application.

jeron12-Dec-13 6:06

2-Dec-13 6:06

So overlay an image of a number on top of an existing icon?

Re: How to add the number to the shortcut in the desktop of the application.

yu-jian2-Dec-13 6:19

2-Dec-13 6:19

Yes, I donot know which windows api can do it.

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