<command arg="-root"/>
+ <video href="https://www.youtube.com/watch?v=rpk3zxQxaR8"/>
+
<number id="delay" type="slider" arg="-delay %"
_label="Frame rate" _low-label="Low" _high-label="High"
low="0" high="100000" default="20000"
<boolean id="showfps" _label="Show frame rate" arg-set="-fps"/>
+ <xscreensaver-updater />
+
<_description>
+A pre-heliocentric model of planetary motion.
+
This draws the path traced out by a point on the edge of a
circle. That circle rotates around a point on the rim of another
-circle, and so on, several times. These were the basis for the
-pre-heliocentric model of planetary motion.
+circle, and so on, several times.
-http://en.wikipedia.org/wiki/Deferent_and_epicycle
+https://en.wikipedia.org/wiki/Deferent_and_epicycle
Written by James Youngman; 1998.
</_description>