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GetTextExtentPoint32 fails on Printer...

If I call hdc = CreateCompatibleDC(hPrinterDC), assuming the printerDC is valid, and then call GetTextExtentPoint(hdc,...), this call crashes the computer everytime. GetTextExtentPoint32 also crashes, but I need to know the size (height and width) of a string for size it will be on the printer. This code works fine for the screen when I am not printing.

What am I doing wrong?

Jordan Pinsker
pinskerj@vu.union.edu

ASKER CERTIFIED SOLUTION

NickRepin

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jordanp

ASKER

Your proposed answer helped a little but did not solve my overall problem. Maybe this will explain things better.

I am creating a bitmap based on the PrinterDC. I draw text to this bitmap to rotate it, and then draw the bitmap to a certain portion of the printed page. Thus, for this to work just as it does for my print preview, I need to create a comaptibleDC for the printer.

I used your suggestion and only changed the GetTextExtentPoint32 to use hPrinterDC, and created the bitmap by calling createcompatiblebitmap(hPrinterDC), but for whatever reason the text is becoming corrupted when printing (it appears that the bitmap is too large and it is printing garbage after the text). I am not sure if this is caused by the differences between the printer and the page as it works fine on screen. Here is my function below:

HANDLE GetRotateText (char * TextName, HWND TitleText, BOOL      left)
{
static LOGFONT lf ;
HBITMAP hBitmap ;
HDC hdc, hdcMem ;
HFONT hFont ;
SIZE size ;
CHARFORMAT        CF;
       BITMAPINFOHEADER      bi;

       if (gPrinter == true) // we are using the printer, not screen
              SetMapMode(hPrinterDC,MM_TEXT);

CF.cbSize = sizeof(CF);
      SendMessage (TitleText,EM_GETCHARFORMAT, 1, (LPARAM)&CF);

hdc = CreateIC ("DISPLAY", nil, nil, nil);
hdcMem = CreateCompatibleDC (hdc);

lf.lfUnderline = (CF.dwEffects & CFE_UNDERLINE);
lf.lfStrikeOut = (CF.dwEffects & CFE_STRIKEOUT);
if (CF.dwEffects & CFE_BOLD)
lf.lfWeight = 700;
else
lf.lfWeight = 400;
       lf.lfItalic = (CF.dwEffects & CFE_ITALIC);

            // Get the size of the text...
       if (false == gPrinter)
             lf.lfHeight = -MulDiv(CF.yHeight/20, GetDeviceCaps(hdcMem,
LOGPIXELSY), 72);
       else
             lf.lfHeight = -MulDiv(CF.yHeight/20, GetDeviceCaps(hPrinterDC,
LOGPIXELSY), 72);

lstrcpy ((char *) lf.lfFaceName, CF.szFaceName) ;

hFont = (HFONT) SelectObject (hdcMem, CreateFontIndirect (&lf));
if (false == gPrinter)
     {
           GetTextExtentPoint32 (hdcMem, TextName, strlen (TextName), &size);
      hBitmap = CreateCompatibleBitmap (hdcMem, size.cy, size.cx) ;//switch x,y for rotation...
            }
else
     {
           GetTextExtentPoint32 (hPrinterDC, TextName, strlen (TextName),
&size);
                  hBitmap = CreateCompatibleBitmap (hPrinterDC, size.cy, size.cx) ;//switch x,y for rotation...
            }

if (left)
lf.lfEscapement = lf.lfOrientation = 900 ;//90 degrees
else
lf.lfEscapement = lf.lfOrientation = 2700 ;//270 degrees

SelectObject (hdcMem, hBitmap) ;
       hFont = (HFONT) SelectObject (hdcMem, CreateFontIndirect (&lf));

       if (left)
             TextOut (hdcMem, 0,size.cx, TextName, strlen (TextName));
       else
TextOut (hdcMem, size.cy,0, TextName, strlen (TextName))

DeleteObject (SelectObject (hdcMem, hFont)) ;
DeleteDC (hdcMem) ;
DeleteDC (hdc) ;

       if (gPrinter == true) // return to twips for the printer...
              SetMapMode(hPrinterDC,MM_TWIPS);

// Now convert the bitmap to a dib and return it...
       bi.biSize = sizeof(BITMAPINFOHEADER);
       bi.biWidth = size.cy;
bi.biHeight = size.cx;
bi.biPlanes = 1;
bi.biBitCount = 16;
bi.biCompression = BI_RGB;
bi.biSizeImage = 0;
bi.biXPelsPerMeter = 0;
bi.biYPelsPerMeter = 0;
bi.biClrUsed = 0;
bi.biClrImportant = 0;

       return (DibFromBitmap (hBitmap,BI_RGB,32,CreateBIPalette (&bi)));

     // must dipose of old bitmap before return hBitmap; not done yet
}

NickRepin

It seems that you use Win95, don't you?
There is no problem to rotate text in WinNT.

As to your code,

1) you should select font on printerDC to call GetTextExtentPoint:

hFont = (HFONT) SelectObject (hdcMem, CreateFontIndirect (&lf));
hPrinterDC = (HFONT) SelectObject (hPrinterDC, CreateFontIndirect (&lf));
// ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
if (false == gPrinter) {
GetTextExtentPoint32 (hdcMem, TextName, strlen (TextName), &size);
hBitmap = CreateCompatibleBitmap (hdcMem, size.cy, size.cx) ;//switch x,y for rotation...
}
else {
GetTextExtentPoint32 (hPrinterDC, TextName, strlen (TextName),&size);
hBitmap = CreateCompatibleBitmap (hPrinterDC, size.cy, size.cx) ;//switch x,y for rotation...
}

2) in my opinion, you should swap lines with TextOut in following code:

if (left)
// 90 degrees, from top to bottom
TextOut (hdcMem, 0,size.cx, TextName, strlen (TextName));
else
// 270 degrees, from bottom to top
TextOut (hdcMem, size.cy,0, TextName, strlen (TextName));

3) why do not to print directly to hPrinterDC (or to screen) by TextOut with lf.lfEscapement=lf.lfOrientation != 0 ?