Abstract: Computer graphics for an industrial process installation or other computer-controlled system in which the system is graphically displayed on the screen of the computer terminal. Each controllable element in the system, such as a valve, a control dial or a switch, is marked on the display by an action point. In order for an operator to select any desired action point on the display to carry out an action appropriate thereto, a cursor is provided which can be manipulated by a key matrix to occupy a position coinciding with any action point thereon. The key matrix is a three-by-three-matrix constituted by a home key surrounded by eighty arrow keys whose arrows are directed to the major axes of a compass rose. Only one action point can be selected at a time. The selected point then effectively becomes the compass center, the previously selected point being then de-selected.