How to scale the viewport to see more?

I can use the glutDisplayFunc() to rotate the stuffs I draw. But this doesn’t work when I want to scale the viewport to see more stuffs. Do I need to use glScale() to scale the stuffs or change the fovy of the gluPerspective()?

What do you mean see more stuffs?
Can’t you just draw more?

I can draw more, but I just can’t see them. At the present, I just can’t understand well what the Viewport is. So, I want to the form to display everything I drawed.

He probably is getting clipped by the near and far plane. If you are using a perspective frustum, then set znear to 0.1 and zfar to 2000.

If you are in ortho projection, then I guess -1000 and 1000.