+Per-frame delay, in microseconds. Default: 30000 (0.03 seconds.).
+.TP 8
+.B \-speed \fInumber\fP
+Speed of disk animation. Default: 12.0 er, units per second. Let's call them metres.
+.TP 8
+.B \-rotspeed \fInumber\fP
+Speed of disk animation. Default: 0.1 rads per second.