1 .TH XScreenSaver 1 "22-mar-93" "X Version 11"
3 attraction - interactions of opposing forces
6 [\-display \fIhost:display.screen\fP] [\-foreground \fIcolor\fP] [\-background \fIcolor\fP] [\-window] [\-root] [\-mono] [\-install] [\-visual \fIvisual\fP] [\-points \fIint\fP] [\-threshold \fIint\fP] [\-mode balls | lines | polygons | splines | filled-splines | tails ] [\-color-mode cycle | random] [\-size \fIint\fP] [\-segments \fIint\fP] [\-delay \fIusecs\fP] [\-color-shift \fIdegrees\fP] [\-radius \fIint\fP] [\-vx \fIint\fP] [\-vy \fIint\fP] [\-glow] [\-noglow] [\-orbit]
8 The \fIattraction\fP program has several visually different modes of
9 operation, all of which are based on the interactions of a set of control
10 points which attract each other up to a certain distance, and then begin
11 to repel each other. The attraction/repulsion is proportional to the
12 distance between any two particles.
15 accepts the following options:
18 Draw on a newly-created window. This is the default.
21 Draw on the root window.
24 If on a color display, pretend we're on a monochrome display.
27 Install a private colormap for the window.
29 .B \-visual \fIvisual\fP
30 Specify which visual to use. Legal values are the name of a visual class,
31 or the id number (decimal or hex) of a specific visual.
34 How many control points should be used, or 0 to select the number randomly.
35 Default 0. Between 3 and 15 works best.
37 .B \-threshold integer
38 The distance (in pixels) from each particle at which the attractive force
39 becomes repulsive. Default 100.
41 .B \-mode "balls | lines | polygons | tails | splines | filled-splines"
42 In \fIballs\fP mode (the default) the control points are drawn as filled
43 circles. The larger the circle, the more massive the particle.
45 In \fIlines\fP mode, the control points are connected by straight lines;
46 the effect is something like \fIqix\fP.
48 In \fIpolygons\fP mode, the control points are connected by straight
49 lines, and filled in. This is most interesting in color.
51 In \fIsplines\fP mode, a closed spline is interpolated from the control
54 In \fIfilled-splines\fP mode, the splines are filled in instead of being
55 outlines. This is most interesting in color.
57 In \fItails\fP mode, the path which each particle follows is indicated
58 by a worm-like trail, whose length is controlled by the \fIsegments\fP
61 .B \-color-mode cycle | random
62 Whether colors should cycle through the spectrum, or be picked randomly.
65 The size of the balls in pixels, or 0, meaning to select the sizes
66 randomly (the default.) If this is specified, then all balls will be
67 the same size. This option has an effect in all modes, since the ``size''
68 of the balls controls their mass.
71 If in \fIlines\fP or \fIpolygons\fP mode, how many sets of line segments
72 or polygons should be drawn. Default 100. This has no effect in \fIballs\fP
73 mode. If \fIsegments\fP is 0, then no segments will ever be erased (this
74 is only useful in color.)
76 .B \-delay microseconds
77 How much of a delay should be introduced between steps of the animation.
78 Default 10000, or about 0.01 seconds.
80 .B \-color-shift degrees
81 If on a color display, the color of the line segments or polygons will
82 cycle through the spectrum. This specifies how far the hue of each segment
83 should be from the next, in degrees on the HSV wheel. Default 3.
84 This has no effect in \fIballs\fP mode.
87 The size in pixels of the circle on which the points are initially positioned.
88 The default is slightly smaller than the size of the window.
91 This is consulted only in \fIballs\fP mode. If this is specified, then
92 the saturation of the colors of the points will vary according to their
93 current acceleration. This has the effect that the balls flare brighter
94 when they are reacting to each other most strongly.
96 In \fIglow\fP mode, all of the balls will be drawn the same (random)
97 color, modulo the saturation shifts. In non-glow mode, the balls will
98 each be drawn in a random color that doesn't change.
101 Don't do ``glowing.'' This is the default.
106 Initial velocity of the balls. This has no effect in \fB\-orbit\fP mode.
109 Make the initial force on each ball be tangential to the circle on which
110 they are initially placed, with the right velocity to hold them in orbit
111 about each other. After a while, roundoff errors will cause the orbit
115 In orbit mode, the initial velocity of the balls is multiplied by this;
116 a number less than 1 will make the balls pull closer together, and a larger
117 number will make them move apart. The default is 1, meaning stability.
122 to get the default host and display number.
125 to get the name of a resource file that overrides the global resources
126 stored in the RESOURCE_MANAGER property.
131 Copyright \(co 1992, 1993 by Jamie Zawinski. Permission to use, copy, modify,
132 distribute, and sell this software and its documentation for any purpose is
133 hereby granted without fee, provided that the above copyright notice appear
134 in all copies and that both that copyright notice and this permission notice
135 appear in supporting documentation. No representations are made about the
136 suitability of this software for any purpose. It is provided "as is" without
137 express or implied warranty.
139 Jamie Zawinski <jwz@mcom.com>, 13-aug-92.