plot(FP)                       6 January 1993                       plot(FP)


 Name

    plot - graphics interface

 Description

    Files of this format are produced by routines described in plot(S) and
    are interpreted for various devices by commands described in tplot(ADM).
    A graphics file is a stream of plotting instructions.  Each instruction
    consists of an ASCII letter usually followed by bytes of binary informa-
    tion.  The instructions are executed in order.  A point is designated by
    four bytes representing the x and y values; each value is a signed
    integer.  The last designated point in an l, m, n, or p instruction
    becomes the ``current point'' for the next instruction.

    Each of the following descriptions begins with the name of the corre-
    sponding routine in plot(S).


    m  move:  The next four bytes generate a new current point.

    n  cont:  Draw a line from the current point to the point given by the
       next four bytes (see tplot(ADM)).

    p  point:  Plot the point given by the next four bytes.

    l  line:  Draw a line from the point given by the next four bytes to the
       point given by the following four bytes.

    t  label:  Place the following ASCII string so that its first character
       falls on the current point.  The string is terminated by a newline
       character.

    e  erase:  Start another frame of output.

    f  linemod:  Take the following string, up to a new line, as the style
       for drawing further lines.  The styles are dotted, solid, longdashed,
       shortdashed, and dotdashed. Effective only for the -T4014 and -Tver
       options of tplot(ADM) (TEKTRONIX 4014 terminal and VERSATEC plotter).

    s  space:  The next four bytes give the lower left corner of the plotting
       area; the following four give the upper right corner.  The plot is
       magnified or reduced to fit the device as closely as possible.

    Space settings that exactly fill the plotting area with unit-y scaling
    are shown for devices supported by the filters of tplot(ADM).  The upper
    limit is just outside the plotting area.  In every case the plotting area
    is taken to be square; points outside may be displayable on devices whose
    face is not square.

    DASI 300          space(0, 0, 4096, 4096);

    DASI 300s         space(0, 0, 4096, 4096);

    DASI 450          space(0, 0, 4096, 4096);

    TEKTRONIX 4014    space(0, 0, 3120, 3120);

    VERSATEC plotter  space(0, 0, 2048, 2048);


 Note

    The plotting library plot(S) and the curses library curses(S) both use
    the names erase and move.  The curses versions are macros. If you need
    both libraries, put the plot(S) code in a different source file than the
    curses(S) code, and/or undefine (using #undef move and erase in the
    plot(S) code.

 See also

    graph(ADM), plot(S), term(M), tplot(ADM)