windowSize

is there a way i can get the window size,i’m implementing a 3D game and i need to know the size of the window,and since the user can change the window size i can’t use the size of the window at the beginning
glutInitWindowSize(640,480);

Use glutReshapeFunc :
http://www.lighthouse3d.com/opengl/glut/index.php?3

thanks that’s just what i needed.