Redefines the current path as the area that would be painted if the path were stroked using the pen currently selected into the device context.
This function is successful only if the current pen is a geometric pen created by the second version of CreatePen member function, or if the pen is created with the first version of CreatePen and has a width, in device units, of greater than 1. The device context must contain a closed path. Any Bzier curves in the path are converted to sequences of straight lines approximating the widened curves. As such, no Bzier curves remain in the path after WidenPath is called.