%
\newcommand{\preview}{{\tt Preview}}
\newcommand{\version}{1.00}
\newcommand{\dvi}{{\tt dvi}}
%
\documentstyle{article}
\title{\preview\\
\rm in the RISCOS desktop}
\author{Edinburgh Software Products\\
very preliminary documentation of\\
\preview\ version \version}
\begin{document}
\maketitle

\noindent

\preview\ enables you to view \TeX\ generated device indenpendent \dvi\
files in the RISCOS desktop.

\section*{Loading a file}

\noindent

A \dvi\ file can be loaded by double-clicking it, or by dragging it onto the
iconbar, or by dragging the directory in which it resides onto the \preview\
icon on the iconbar.  In the latter case, the file {\em must} be called
\dvi.

\preview\ loads the first page of a file immediately, and any subsequent
pages in the background.  Each page is available for viewing as soon as it
has been loaded completely.

Normally the titlebar of a window shows the name of the file and the
cardinal number of the page being shown.  While still loading a file, it will
also show an asterisk.  The asterisk will disappear as soon as the whole
file has been loaded.

\section*{Remarks}

\noindent

A few things are worth noting about this version \version\ of \preview:

\begin{itemize}

\item

\preview\ puts each page being displayed into a sprite.  This sprite's
screenmode is the same as the current screenmode, which makes for very fast
window updating.  Another consequence is that by choosing a different
screenmode you influence the quality of the display.  But be careful: An A4
page magnified to {\tt $\backslash$magstep5} in mode 12 takes about 1.9 {\em
MEGA}\/bytes of memory.

\item

\preview\ uses RISCOS outline\footnote{Only the Computer Modern font family
is available as outlines. Other fonts will be available as 300dpi bitmaps.}
fonts to draw characters.  The advantage of using outlines is that they only
take about 20\% of the diskspace needed to store a full set of {\tt pk}
files, and they can be plotted at any pointsize.

\item

Due to the number
of \TeX\ fonts, the fonts are kept within the directory of \preview, and 
are not included in the {\tt Font\$Path}.  A lot of utilities can't stand
the sight of many fonts (esp.\ {\tt !Edit}, {\tt !FormEd} and {\tt !Draw}).

\item

If an error occurs while reading a dvi file, \preview\ exits after having
shown an error box which sort-of tells you what the problem was.

\end{itemize}


\vfill
\section*{About\ldots}
\begin{flushleft}
This is \preview\ version \version.\\
Copyright 1990 Graham Toal and Pieter Schoenmakers.
\end{flushleft}
\end{document}
