C / C++ / MFC

"Ideas are a dime a dozen. People who put them into action are priceless." - Unknown

"Ideas are a dime a dozen. People who put them into action are priceless." - Unknown

void modifyvariable(int **varB)
{
    int temp;
    *varB = &temp;
}
 
void main()
{
    int varA;
    int *p = &varA;
    // here &varA and p both have the same value
    modifyvariable(&p);
    // here p points to the address of temp
}

"Ideas are a dime a dozen. People who put them into action are priceless." - Unknown

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

//! Checks whether a directory exists.
//! @param  strDirectory  Directory
//! @return true if the directory exists, false otherwise.
bool dirExists
  (CString strDirectory)
{
  // Create full directory specification - return if unable
  TCHAR* fullPath = _tfullpath (NULL, strDirectory, 0);
  if (fullPath == NULL)
     return (false);
 
  // Check if directory exists by trying to make it the default directory
  TCHAR szCurrDir [_MAX_PATH];
  _tgetcwd (szCurrDir, _MAX_PATH - 1);
  long nStatus = _tchdir (fullPath);
  _tchdir (szCurrDir);
 
  // Return
  free (fullPath);    
  if (nStatus == 0)
     return (true);
  return (false);
}

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

void DrawSmoothedPolygon(HDC dc, POINT *pointlist, int pointcount)
{
   const float curvyness = 0.1f;

   float prevseglength, nextseglength;
   long dx, dy;
   long leapfrogdx, leapfrogdy;

   ASSERT(pointlist != NULL);
   ASSERT(pointcount >= 3);

   POINT *curvepoints = new POINT[pointcount * 3 + 1];

   curvepoints[0] = pointlist[i];
   curvepoints[1] = pointlist[i];
   curvepoints[pointcount * 3 + 1] = pointlist[pointcount];
   curvepoints[pointcount * 3] = pointlist[pointcount];

   dx = (curvepoints[1].x - curvepoints[0].x);
   dy = (curvepoints[1].y - curvepoints[0].y);

   nextseglength = sqrt(dx*dx + dy*dy);
   
   for(int i = 1; i < pointcount - 1; i++)
   {
      leapfrogdx = (curvepoints[i-1].x - curvepoints[i+1].x);
      leapfrogdy = (curvepoints[i-1].y - curvepoints[i+1].y);

      preveglength = nextseglength;
      dx = (curvepoints[i+1].x - curvepoints[i].x);
      dy = (curvepoints[i+1].y - curvepoints[i].y);
      nextseglength = sqrt(pointlist[i].x * pointlist[i].x + pointlist[i].y * pointlist[i].y);

      curvepoints[i * 3] = pointlist[i];

      curvepoints[i * 3 + 1].x = pointlist[i].x + leapfrogdx / (nextseglength / curvyness);
      curvepoints[i * 3 + 1].y = pointlist[i].y + leapfrogdy / (nextseglength / curvyness);
      curvepoints[i * 3 - 1].x = pointlist[i].x - leapfrogdx / (prevseglength / curvyness);
      curvepoints[i * 3 - 1].y = pointlist[i].y - leapfrogdy / (prevseglength / curvyness);
   }

   PolyBezier(dc, curvepoints, pointcount * 3 + 1);
   delete[] curvepoints;
}