public static void WindingModeOutline(this GraphicsPath graphicsPath) { IntPtr handle = (IntPtr)graphicsPath.GetType().GetField("nativePath", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(graphicsPath); HandleRef path = new HandleRef(graphicsPath, handle); NativeMethods.GdipWindingModeOutline(path, IntPtr.Zero, 0.25F); }