attraction - interactions of opposing forces
.SH SYNOPSIS
.B attraction
-[\-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 ] [\-size \fIint\fP] [\-segments \fIint\fP] [\-delay \fIusecs\fP] [\-color-shift \fIint\fP] [\-radius \fIint\fP] [\-vx \fIint\fP] [\-vy \fIint\fP] [\-glow] [\-noglow] [\-orbit] [\-viscosity \fIfloat\fP] [\-mouse] [\-no-mouse] [\-mouse-size]
+[\-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 ]
+[\-size \fIint\fP] [\-segments \fIint\fP] [\-delay \fIusecs\fP]
+[\-color-shift \fIint\fP] [\-radius \fIint\fP]
+[\-vx \fIint\fP] [\-vy \fIint\fP] [\-glow] [\-noglow]
+[\-orbit] [\-viscosity \fIfloat\fP]
+[\-walls] [\-nowalls] [\-maxspeed] [\-nomaxspeed]
+[\-correct-bounce] [\-fast-bounce]
+[\-fps]
.SH DESCRIPTION
The \fIattraction\fP program has several visually different modes of
operation, all of which are based on the interactions of a set of control
.TP 8
.B \-segments integer
If in \fIlines\fP or \fIpolygons\fP mode, how many sets of line segments
-or polygons should be drawn. Default 100. This has no effect in \fIballs\fP
+or polygons should be drawn. Default 500. This has no effect in \fIballs\fP
mode. If \fIsegments\fP is 0, then no segments will ever be erased (this
is only useful in color.)
.TP 8
One interesting thing to try is
.EX
-attraction -viscosity 0.8 -points 75 \\
- -mouse -geometry =500x500
+attraction -viscosity 0.8 -points 300 -size 10 -geometry =500x500
.EE
Give it a few seconds to settle down into a stable clump, and then move
-the mouse through it to make "waves".
-.TP 8
-.B \-mouse
-This will cause the mouse to be considered a control point; it will not be
-drawn, but it will influence the other points, so you can wave the mouse
-and influence the images being created.
-.TP 8
-.B \-no-mouse
-Turns off \fB\-mouse\fP.
-.TP 8
-.B \-mouse-size integer
-In \fB\-mouse\fP mode, this sets the mass of the mouse (analagously to the
-\fB\-size\fP parameter.)
+the drag the mouse through it to make "waves".
+.TP 8
+.B \-nowalls
+This will cause the balls to continue on past the edge of the
+screen or window. They will still be kept track of and can come back.
+.TP 8
+.B \-walls
+This will cause the balls to bounce when they get
+to the edge of the screen or window. This is the default behavior.
+.TP 8
+.B \-maxspeed
+Imposes a maximum speed (default). If a ball ends up going faster than
+this, it will be treated as though there were .9 viscosity until it is
+under the limit. This stops the balls from continually accelerating (which
+they have a tendency to do), but also causes balls moving very fast to
+tend to clump in the lower right corner.
+.TP 8
+.B \-nomaxspeed
+If this is specified, no maximum speed is set for the balls.
+.TP 8
+.B \-fast-bounce
+Uses the old, simple bouncing algorithm (default). This simply moves any
+ball that is out of bounds back to a wall and reverses its velocity.
+This works fine for most cases, but under some circumstances, the
+simplification can lead to annoying effects.
+.TP 8
+.B \-correct-bounce
+Uses a more intelligent bouncing algorithm. This method actually reflects
+the balls off the walls until they are within bounds. This can be slow
+if balls are bouncing a whole lot, perhaps because of -nomaxspeed.
+.TP 8
+.B \-graphmode none | x | y | both | speed
+For "x", "y", and "both", displays the given velocities of each ball as a
+bar graph in the same window as the balls. For "speed", displays the total
+speed of each ball. Default is "none".
+.BR
+.TP 8
+.B \-fps
+Display the current frame rate and CPU load.
.SH ENVIRONMENT
-.PP
-.TP 8
.B DISPLAY
to get the default host and display number.
.TP 8
made about the suitability of this software for any purpose. It is provided
"as is" without express or implied warranty.
.SH AUTHOR
-Jamie Zawinski <jwz@netscape.com>, 13-aug-92.
+Jamie Zawinski <jwz@jwz.org>, 13-aug-92.
+
+Viscosity support by Philip Edward Cutone, III.
-Viscosity and mouse support by Philip Edward Cutone, III.
+Walls, speed limit options, new bouncing, graphs, and tail mode fix by
+Matthew Strait. 31 March 2001
projects / xscreensaver / blobdiff