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CDC::BeginPath

Opens a path bracket in the device context.

BOOL BeginPath();

Nonzero if the function is successful; otherwise 0.

After a path bracket is open, an application can begin calling GDI drawing functions to define the points that lie in the path. An application can close an open path bracket by calling the EndPath member function. When an application calls BeginPath, any previous paths are discarded.

See BeginPath in the Windows SDK for a list of the drawing functions that define points in a path.

// This implementation uses GDI paths to draw the outline of 
// some text in a TrueType font. The path is used to record the way 
// the TrueType font would be drawn. Then, the function uses the data 
// returned from CDC::GetPath() to draw the font--without filling it. 
void CDCView::DrawPath(CDC* pDC)
{
   // Describe a 24-point truetype font of normal weight
   LOGFONT lf;
   memset(&lf, 0, sizeof(lf));
   lf.lfHeight = -MulDiv(24, pDC->GetDeviceCaps(LOGPIXELSY), 72);
   lf.lfWeight = FW_NORMAL;
   lf.lfOutPrecision = OUT_TT_ONLY_PRECIS;

   // create and select it
   CFont newFont;
   if (!newFont.CreateFontIndirect(&lf))
      return;
   CFont* pOldFont = pDC->SelectObject(&newFont);

   // use a path to record how the text was drawn
   pDC->BeginPath();
   pDC->TextOut(10, 10, _T("Outline this!"));
   pDC->EndPath();

   // Find out how many points are in the path. Note that 
   // for long strings or complex fonts, this number might be 
   // gigantic! 
   int nNumPts = pDC->GetPath(NULL, NULL, 0);
   if (nNumPts == 0)
      return;

   // Allocate memory to hold points and stroke types from 
   // the path.
   LPPOINT lpPoints = NULL;
   LPBYTE lpTypes = NULL;
   try
   {
      lpPoints = new POINT[nNumPts];
      lpTypes = new BYTE[nNumPts];
   }
   catch (CException* pe)
   {
      delete [] lpPoints;
      lpPoints = NULL;
      delete [] lpTypes;
      lpTypes = NULL;
      pe->Delete();	
   }
   if (lpPoints == NULL || lpTypes == NULL)
      return;

   // Now that we have the memory, really get the path data.
   nNumPts = pDC->GetPath(lpPoints, lpTypes, nNumPts);

   // If it worked, draw the lines. Windows 98 doesn't support 
   // the PolyDraw API, so we use our own member function to do 
   // similar work. If you're targeting only later versions of  
   // Windows, you can use the PolyDraw() API and avoid the  
   // COutlineView::PolyDraw() member function. 

   if (nNumPts != -1)
      pDC->PolyDraw(lpPoints, lpTypes, nNumPts);

   // Release the memory we used 
   delete [] lpPoints;
   delete [] lpTypes;

   // Put back the old font
   pDC->SelectObject(pOldFont);

   return;
}

Header: afxwin.h

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