PLOT(VI) 3/10/75 PLOT(VI)
NAME
plot: tek, gsip, vt0 - graphics filters
SYNOPSIS
source | tek
source | gsip
source | vt0
DESCRIPTION
These commands produce graphical output on the Tektronix
4014 terminal, the GSI or other Diablo-mechanism terminals,
and the on-line storage scope respectively. They read the
standard input to obtain plotting instructions, which are
usually generated by a program calling the graphics
subroutines described in plot (VII). Each instruction
consists of an ASCII letter usually followed by binary
information. A plotting coordinate is transmitted as four
bytes representing the x and y values; each value is a
signed number transmitted low-order byte first. The assumed
plotting space is set by request. The instructions are
taken from
m move: the next four bytes specify the coordinates of a
point to move to. This is used before writing a label.
p point: the next four bytes specify the coordinates at
which a point is drawn.
l line: the next eight bytes are taken as two pairs of
coordinates specifying the endpoints of a line to be
drawn.
t label: the bytes up to a new-line are written as ASCII
starting at the last point drawn or moved to.
a arc: the first four bytes specify the center, the next
four specify the starting point, and the last four
specify the end point of a circular arc. The least
significant coordinate of the end point is used only to
determine the quadrant. The arc is drawn counter-
clockwise. This command is not necessarily implemented
on all (or even any) of the output devices.
c circle: The first four bytes specify the center of the
circle, the next two the radius.
e erases the screen
f linemod: takes the following string as the type for all
future lines. The types are `dotted,' `solid,'
`longdashed,' `shortdashed,' and `dotdashed.' This
instruction is effective only with the Tektronix
terminal.
d dotline: takes the first four bytes as the coordinates
of the beginning of a dotted line. The next two are a
signed x-increment, and the next two are a word count.
Following are the indicated number of byte-pairs
representing words. For each bit in this list of words a
point is plotted which is visible if the bit is `1,'
invisible if not. Each point is offset rightward by the
x-increment. The instruction is effective only on the
vt0 scope.
SEE ALSO
plot (VII), graph (VI)
BUGS