glschool man page

glschool — a 3D schooling simulation


glschool [-display host:display.screen] [-visual visual] [-window] [-root] [-wireframe] [-fps] [-delay number] [-nfish number] [-maxvel number] [-minvel number] [-acclimit number] [-avoidfact number] [-matchfact number] [-centerfact number] [-targetfact number] [-minradius number] [-momentum number] [-distexp number] [-goalchgf number] [-fog] [-drawgoal] [-drawbbox]


Uses Craig Reynolds Boids algorithm to simulate a 3d school of fish. See <> for a description of the algorithm and the original paper. This is a lightly modified version of the algorithm that supports goal attraction.

Many different behaviors are possible by tweaking the parameters. No sanity checking is performed on the command line params, so if you want to use negative accelerations or minimum velocity that is larger than maximum velocity or that sort of thing, the simulation will try to digest it.

It looks best with the highest number of fish that will give you an FPS of > 25 or so.


-visual visual
Specify which visual to use. Legal values are the name of a visual class, or the id number (decimal or hex) of a specific visual.
Draw on a newly-created window. This is the default.
Draw on the root window.
-delay number
Per-frame delay, in microseconds. Default: 20000 (0.020 seconds.).
-wireframe | -no-wireframe
Render in wireframe instead of solid.
Display the current frame rate, CPU load, and polygon count.
-fog | -no-fog
Whether to show foggy (cloudy) water.
-drawgoal | -no-drawgoal
Whether to show the school's attraction goal.
-drawbbox | -no-drawbbox
Whether to show the bounding box.
-fog | -no-fog
Whether to show foggy (cloudy) water.
-nfish number
Number of fish. Defaults to 100
-acclimit number
Acceleration limit. Defaults to 8.0
-minvel number
Minimum velocity. Defaults to 1.0
-maxvel number
Minimum velocity. Defaults to 7.0
-goalchgf number
Goal change frequency. Defaults to 50 (frames)
-avoidfact number
Avoidance acceleration factor. Defaults to 1.5
-matchfact number
Match avg velocity acceleration factor. Defaults to 0.15
-centerfact number
School centering acceleration factor. Defaults to 0.1
-targetfact number
Target attraction acceleration factor. Defaults to 80
-distexp number
Distance weighting exponent. Defaults to 2.2
-momentum number
Momentum. Defaults to 0.9


to get the default host and display number.
to get the name of a resource file that overrides the global resources stored in the RESOURCE_MANAGER property.

See Also

X(1), xscreensaver(1)


David C. Lambert


5.36-3.fc26 (21-Oct-2016) X Version 11 XScreenSaver manual