1 <?xml version="1.0" encoding="ISO-8859-1"?>
3 <screensaver name="epicycle" _label="Epicycle">
7 <video href="https://www.youtube.com/watch?v=rpk3zxQxaR8"/>
9 <number id="delay" type="slider" arg="-delay %"
10 _label="Frame rate" _low-label="Low" _high-label="High"
11 low="0" high="100000" default="20000"
14 <number id="ncolors" type="slider" arg="-colors %"
15 _label="Number of colors" _low-label="Two" _high-label="Many"
16 low="1" high="255" default="100"/>
18 <number id="holdtime" type="slider" arg="-holdtime %"
19 _label="Linger" _low-label="1 second" _high-label="30 seconds"
20 low="1" high="30" default="2"/>
23 <number id="linewidth" type="spinbutton" arg="-linewidth %"
24 _label="Line thickness" low="1" high="50" default="4"/>
26 <number id="harmonics" type="spinbutton" arg="-harmonics %"
27 _label="Harmonics" low="1" high="20" default="8"/>
30 <!-- #### -color0 [red] -->
31 <!-- #### -colours [100] -->
32 <!-- #### -foreground [white] -->
33 <!-- #### -min_circles [2] -->
34 <!-- #### -max_circles [10] -->
35 <!-- #### -min_speed [0.003] -->
36 <!-- #### -max_speed [0.005] -->
37 <!-- #### -timestep [1.0] -->
38 <!-- #### -divisor_poisson [0.4] -->
39 <!-- #### -size_factor_min [1.05] -->
40 <!-- #### -size_factor_max [2.05] -->
42 <boolean id="showfps" _label="Show frame rate" arg-set="-fps"/>
44 <xscreensaver-updater />
47 A pre-heliocentric model of planetary motion.
49 This draws the path traced out by a point on the edge of a
50 circle. That circle rotates around a point on the rim of another
51 circle, and so on, several times.
53 https://en.wikipedia.org/wiki/Deferent_and_epicycle
55 Written by James Youngman; 1998.