Why doesn't this gdiplus GraphicsPath code work?

Question

Hi! I am trying to learn to use the gdiplus GraphicsPath class and wrote some code to test the setup, but the number of points always returns 0. What is wrong with this code?

#include <windows.h>
#include <gdiplus.h>
#include <iostream>

//use gdiplus library when compiling
#pragma comment( lib, "gdiplus" )

using namespace Gdiplus;

VOID GetPointCountExample()
{
    // Create a path that has one ellipse and one line.
    GraphicsPath path;
    path.AddLine(220, 120, 300, 160);

    // Find out how many data points are stored in the path.
    int count = path.GetPointCount();
    std::cout << count << std::endl;
}

int main()
{
    GetPointCountExample();
}

Answer 1

Try initialising the engine:

int main()
{
   ULONG_PTR t;
   Gdiplus::GdiplusStartupInput s;
   Gdiplus::GdiplusStartup( &t, &s, nullptr );
   . . .
}