glutDisplayFunc Two

OpenGL
1

In the commands to open a window for the OpenGL commands, as below, having trouble with the glutDisplayFunc and glutIdleFunc “display” argument, what is it or how is it declared. Keep getting an error from the Visual Studio, C++ linking that says variable not define or declared? not sure what the function is or does, Sid Kraft,

 //open a window
 //int glut1 = 659;
 //string glutstr;
 int argc;
 char  **argv;
 glutInit(&argc, argv);
 //glutInit(&glut1, glutstr);

 glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH);
 glutInitWindowPosition(100, 200);

 //this sets the size for the window
 glutInitWindowSize(800, 700);

 //create the window with a title
 glutCreateWindow("This is a window title");
 //this is the method that will have all the draw stuff.
 glutDisplayFunc(display);
 glutIdleFunc(display);
 glutMainLoop();
2

The various glut*Func functions are used to register callback functions which you write yourself.

You should start with a tutorial, e.g.

https://www.lighthouse3d.com/tutorials/glut-tutorial/