C / C++ / MFC

6-Sep-07 16:34

All the code looks like it's for 8-bit images only (and assumes a WORD aligned width).

If the source bitmap is not 8-bitsperpixel, then you need to use bBitmap.bmWidthBytes
instead of bBitmap.bmWidth when calculating array size and offset of pixel in buffer.

Plus, if it's < 8 bpp, you need to mask out the appropriate bits to match the color.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Re: I solved it now!

zqueezy6-Sep-07 20:57

zqueezy

6-Sep-07 20:57

so for anybody who's intrested and for the sake of completeness:

BOOL CMeineFormDlg::OnInitDialog()
{
	CDialog::OnInitDialog();

	// Symbol für dieses Dialogfeld festlegen. Wird automatisch erledigt
	//  wenn das Hauptfenster der Anwendung kein Dialogfeld ist
	SetIcon(m_hIcon, TRUE);					// Großes Symbol verwenden
	SetIcon(m_hIcon, FALSE);				// Kleines Symbol verwenden

	// TODO: Hier zusätzliche Initialisierung einfügen

	CBitmap bg_Image;						// Bild erstellen
	bg_Image.LoadBitmap(IDB_BITMAP1);		// Bild aus Resource laden

	BITMAP bBitmap;							// Damit man auf die Daten des Bitmap zugreifen kann
	bg_Image.GetBitmap(&bBitmap);			// Daten reinladen aus dem CBitmap
	
	int  iByteSize = bBitmap.bmWidthBytes * bBitmap.bmHeight * (bBitmap.bmBitsPixel/8);
    BYTE *pBuffer = new BYTE[iByteSize];

	bg_Image.GetBitmapBits(iByteSize, pBuffer);

	CRgn    newRgn;							// Eine neue Region für den Dialog
	newRgn.CreateRectRgn(0,0,0,0);

	CRgn	tmpRgn;							// Eine Temporäre Region
	
	int iOffset = bBitmap.bmBitsPixel/8;
	int r,g,b,c;
	for (int y=0; y< bBitmap.bmHeight; ++y)
	{
		for (int x=0; x < bBitmap.bmWidth; ++x)
		{
			c = y*bBitmap.bmWidthBytes + x*iOffset;
			r = pBuffer[c+2];
			g = pBuffer[c+1];
			b = pBuffer[c];

			if (r == 255 && g == 255 && b == 255)					// weiß
			{
				tmpRgn.DeleteObject();								// Die Region erstmal leer machen
				tmpRgn.CreateRectRgn(x,y,x+1,y+1);
				newRgn.CombineRgn(&newRgn, &tmpRgn, RGN_OR);
			}
		}
	}
	this->SetWindowRgn(newRgn, true);
	delete [] pBuffer;


	return TRUE;  // Geben Sie TRUE zurück, außer ein Steuerelement soll den Fokus erhalten
}

Re: I solved it now!

Mark Salsbery7-Sep-07 6:00

Writing integer values to file using streams [modified]

7-Sep-07 6:00

zqueezy wrote:
int iByteSize = bBitmap.bmWidthBytes * bBitmap.bmHeight * (bBitmap.bmBitsPixel/8);

...as long as you only use bitmaps witha format >= 8 bitsperpixel Smile | :)

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Cyrilix6-Sep-07 12:33

Cyrilix

6-Sep-07 12:33

I'm having a little trouble writing integer values to a file with ofstream objects. If I do ofstream::write(), then I have to pass it a char or a char*. So far, in my code, I've tried doing the following:

ofstream geomFile("C:\\file.dat", ios::binary);
geomFile.write((char*)ordX, sizeof(int) * numOrds);
geomFile.write((char*)ordY, sizeof(int) * numOrds);

where ordX and ordY are defined here:

const int numOrds = 10;
int ordX[numOrds];
int ordY[numOrds];

Basically, since I know the array is a contiguous memory location of 10 integers, I do a write starting from the pointer value of ordX and ordY through sizeof(int) (4) * numOrds (10) = 40 bytes. What I expect is to have 20 4-byte integers lined up in my file one after another. Unfortunately, when I read back from the file, I'm not getting the right result. Any ideas?

I guess I should also specify how I'm reading back the file using an ifstream object.

ifstream geomFile("C:\\geom.dat", ios::binary);
char readBuf[sizeof(int)];
int ordX[numOrds];

for (int i = 0; i < 10; i++)
{
    geomFile.get(readBuf, 4);
    ordX[i] = *(int*)readBuf;
}

I know the above looks a bit like a hack, but I'm sort of confused as to how I'd manipulate things in 4-byte blocks other than casting to int* and dereferencing.

-- modified at 20:45 Thursday 6th September, 2007

Mark Salsbery6-Sep-07 14:29

6-Sep-07 14:29

Does something like this work better?

ofstream geomFile("C:\\file.dat", ios::binary);
for (int i = 0; i < numOrds; ++i)
   geomFile << ordX[i];
for (int i = 0; i < numOrds; ++i)
   geomFile << ordY[i];

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Cyrilix6-Sep-07 14:36

Cyrilix

6-Sep-07 14:36

I'm pretty sure this will write the characters to file in ASCII, won't it? I was trying to write it as binary. The thing is, I'm trying to do a minimalist database design, so writing out the x and y ordinates of 13945 and 19053 as ASCII would take 10 bytes, whereas as a 32-bit int, would only take 8 bytes.

Mark Salsbery6-Sep-07 16:18

6-Sep-07 16:18

Cyrilix wrote:
I'm pretty sure this will write the characters to file in ASCII, won't it?

Yes. Sorry about that! D'Oh! | :doh:

I tested your code and it writes binary fine. Reloading worked too, tested as follows:

...

for (int i = 0; i < numOrds; ++i)
{
    ordX[i] = 0;
    ordY[i] = 0;
}

ifstream instream("C:\\file.dat", ios::in);
instream.read((char*)ordX, sizeof(int) * numOrds);
instream.read((char*)ordY, sizeof(int) * numOrds);
instream.close();

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Override afx msg box (pop up)

Cyrilix6-Sep-07 16:57

Cyrilix

6-Sep-07 16:57

Hi Mark,

Thanks a lot for giving this a try -- I guess it was just a matter of me using get() instead of read(). D'Oh! | :doh:

AeJai6-Sep-07 10:04

AeJai

6-Sep-07 10:04

The software I am coding uses AfxThrowArchiveException(CArchive::none) to undo changes made by partially loading a document into the program. However, another afx message stating "Failed to open document." pops up and the operator has to again click OK on the dialog. Is there anyway to override this second message box from popping up?

Re: Override afx msg box (pop up)

Mark Salsbery6-Sep-07 13:53

Is there an equivalent to SuspendLayout/ResumeLayout for a MFC Dialog ?

6-Sep-07 13:53

You could override CDocument::ReportSaveLoadException() in your document class
and do something more appropriate (like not calling AfxMessageBox(), logging the
error, etc).

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Console redirection

Waldermort6-Sep-07 9:22

Waldermort

6-Sep-07 9:22

I know there are numerous articles on this topic, but I haven't found a solution to my problem.

From my GUI app I launch a stub process which is supposed to give me real time feedback on the output of a third console. Basically I set up the pipes and handles from the GUI, launch the stub which inturn modifies it's screen buffer and launches the real console. All the handles are inherited correctly, until I modify the memory of the real console.

I coded the stub to start the new process with the CREATE_SUSPENDED flag set, it also returns the ID's back to the GUI. From there I modify the memory and call ResumeThread(). But, for some reason, the STD_OUTPUT_HANDLE which it should have inherited from the stub has been lost. I have verified that the real console is indeed running, though it has no 'visible' screen buffer to output it's contents to.

Through inheritance, I do get the screen contents, but not in real time and without any of the modifications that the stub was supposed to perform.

Any ideas as to how or why this might have happened? Is there any way I can reset the std_output handle after a call to CreateProcess() ?

Re: Console redirection

Waldermort6-Sep-07 11:59

Waldermort

6-Sep-07 11:59

I don't know how why where or what, but after 6 hours of debuging, editing, rearranging and shouting at the PC, I finaly got it to work. ( I think the shouting did it ).

I can now launch a console from the resources, without writing it to disk first, and redirect it's input/output in real time.

abiemann6-Sep-07 7:00

Re: Is there an equivalent to SuspendLayout/ResumeLayout for a MFC Dialog ?

6-Sep-07 7:00

I love using SuspendLayout and ResumeLayout in .Net to avoid flicker, however, these don't seem to exist for an MFC Dialog.

Is there an equivalent to use on my MFC Dialog ?

David Crow6-Sep-07 7:09

David Crow

6-Sep-07 7:09

Are you looking for SetRedraw()?

"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

Re: Is there an equivalent to SuspendLayout/ResumeLayout for a MFC Dialog ?

abiemann6-Sep-07 7:36

Re: Is there an equivalent to SuspendLayout/ResumeLayout for a MFC Dialog ? [modified]

6-Sep-07 7:36

Thanks David, that sounds like the ideal method to use Smile | :)

abiemann6-Sep-07 8:03

Re: Is there an equivalent to SuspendLayout/ResumeLayout for a MFC Dialog ?

6-Sep-07 8:03

The controls still flicker Frown | :-(

my overall process is:

<br />
//Dialog - prevent changes from being redrawn<br />
this->SetRedraw(FALSE);<br />
<br />
//invert parts of static image onthe Dialog, behind the controls<br />
pDC = this->GetDC();<br />
targetDC.CreateCompatibleDC(pDC);<br />
pOldTargetBmp = targetDC.SelectObject(&m_BmpTarget);<br />
targetDC.PatBlt(X,Y,iWidth,iHeight,DSTINVERT);<br />
targetDC.SelectObject(pOldTargetBmp);<br />
targetDC.DeleteDC();<br />
ReleaseDC(pDC);<br />
m_DialogStaticImage.SetBitmap(HBITMAP(m_BmpTarget));<br />
<br />
//redraw all controls to put them into foreground<br />
m_staticText.RedrawWindow(NULL,NULL,RDW_UPDATENOW);<br />
m_editBox.RedrawWindow(NULL,NULL,RDW_FRAME+RDW_INVALIDATE+RDW_UPDATENOW);<br />
.<br />
. about 15 controls<br />
.<br />
<br />
//Dialog - allow changes to be redrawn<br />
this->SetRedraw(TRUE);<br />
<br />
//no need to erase background since SetBitmap covered everything up<br />
this->Invalidate(FALSE);<br />
<br />
//show updated Dialog<br />
this->UpdateWindow();<br />

I was surprised that it would still flicker; I was hoping that all the graphics operations were done in memory, then simply shown when UpdateWindow was called - thus avoiding flicker.

Mark Salsbery6-Sep-07 8:22

Re: Is there an equivalent to SuspendLayout/ResumeLayout for a MFC Dialog ?

6-Sep-07 8:22

I don't believe WM_SETREDRAW is supported by dialogs. You can try it on the individual controls though Smile | :)

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Mark Salsbery6-Sep-07 8:27

Re: Is there an equivalent to SuspendLayout/ResumeLayout for a MFC Dialog ? [modified]

6-Sep-07 8:27

abiemann wrote:
I was surprised that it would still flicker; I was hoping that all the graphics operations were done in memory, then simply shown when UpdateWindow was called - thus avoiding flicker.

Nope. Looking more closely at your code, the only way you'll be able to prevent flicker
is to do the drawing offscreen yourself, then blt the whole thing to the dialog.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

abiemann6-Sep-07 8:33