Setting new rotation point

i have implemented an arcball camera, but right now it’s only rotationg around the origin, what i want is to set a new rotation point to rotate about, but also that this point is centered on the screen. any tips

glTranslatef(0, 0, cameraOffset); // How far away from the origin the camera should be
//
glTranslatef(-xCamera, -yCamera, -zCamera); // The position of the camera in the world
//

doesn’t seems to work, it looks now if i am in the center of the arcball, and not looking at it.

cheers,

Paul