How to ensure a vertex inside the window?

Hi all,

I often draw vertex outside the window, ie, my window is 800x480 and my settings are as follow:

glViewport(0, 0, 800, 480);
gluPerspective(90.0f, 800/480, 0.1f, 100.0f);
glTranslatef(1.0f, 0.0f, -6.0f);

i dont know where is the left/right/top/bottom most point that
i can draw.
ie, is the point(-5.0f, 0.0f, 0.0f) inside my window? what about the point(-7.0f, 0.0f, 0.0f)?

Check this:

Hi Rosario Leonardi,

Thanks for your help! I will read it, thanks again!