% This file desribes the additional feature for the ATARI ST version
% of GNUPLOT 3.0

% Author: Alexander Lehmann	02/15/1992

% this file is used as a supplement until the doc is included in the general
% release of GNUPLOT. As long as the ATARI version is a patch, this file will
% supply the necessary information.

% for comments contact: alexlehm@iti.informatik.th-darmstadt.de

\documentstyle{article}

\title{GNUPLOT 3.0\\for ATARI ST}

\author{Alexander Lehmann}

\begin{document}

\maketitle
Additional Information for the ATARI ST port of GNUPLOT 3.0

\section{Terminal}

The terminal for ATARI is called {\tt atari} and can be used with options to
set the screen colors. The drivers expects a space sperated list of maximal
3 digit hex numbers where each digit represents RED, GREEN and BLUE in that
order. The range of 0-15 is scaled to whatever color range the screen
actually has. On a normal ST screen odd and even intensities are the same.

Examples:
\begin{itemize}
\item {\tt set terminal atari 0} sets monochrome screen to white on black
\item {\tt set t atari 0 fff f00 f0 f ff f0f ff0} set first eight colors
to black, white, red, green, blue, cyan, purple and yellow
\end{itemize}

Additionally if a environment variable {\tt GNUCOLORS} exists, the contents are
interpreted as palette, but an explicit terminal option take precedence.

Though until now not tested, I expect the code to run on TT models and special
screens like overscan. (The driver uses only {\tt VDI}-calls.)

\section{Shell}

The {\tt shell} command checks the environment variable {\tt SHELL} and
tries to run a program of the name found there or {\tt gulam.prg}, if not
{\tt SHELL} entry is present.

The {\tt !} command first checks whether a shell is already loaded 
(\verb+shell_p+) or tries to call the command directly.

When in gul\"am {\tt !ls} give a directory, even if no {\tt ls}
program is present.

{\tt !cd} might work with certain shells, but the use of the gnuplot {\tt cd}
is recommended.

\end{document}
