The two 16-mm films ROTATIONS and PROJECTIONS (originally ROTATIONEN and PROJEKTIONEN) used one of the earliest three-dimensional programs for the graphic real-time output as a projection on a two dimensional screen. They were calculated and displayed with an interactive graphic screen of the Siemens Research Laboratory, Munich, in connection with a digital data processing unit. The unit allowed interactive operation – work under interactive visual control; a keyboard was used to change the elements interactively – for example, by specifying the number of picture elements, the angle of intersection, the speed of the sequence, and so on. The movement could be stopped for a static image at any time. Ces séquences de film de PROJEKTIONEN ont été utilisées en 1974 comme décor, projeté sur un écran, pour un spectacle de danse expérimentale avec Gerald Bohner dans la « Experimentierbuehne » de l'Opéra d'État de Bavière à Munich, sous la direction de Walter Haupt.