Toy model of a clockwise rigidly rotating logarithmic spiral with a swinging motion. Panel a: snapshot of the logarithmic spiral with the red circle denoting the circular slit used for the time-angle slices of panels c and d with the clockwise angle defined as in Fig. 12 (panel b). The arrow indicates the direction of the imposed swinging motion. Panel b: time-slice image along the green horizontal slit of panel a. Panel c: time-angle slice along the circular red slit of panel a with the swinging motion inhibited. Panel d: same as panel c, but with swinging motion. In all panels we have used arbitrary spatial and temporal units while the logarithmic spiral has been rotated six times with a rotational period T _rot.