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Acorn XEarth             v0.10 (06 Jul 1998)

                       original code by  Kirk Johnson <tuna@cs.colorado.edu>

                          Acorn port by Matthew Bloch <mattbee@eh.org>

                         with thanks to Stefan Bellon
                                <bellonsn@trick.informatik.uni-stuttgart.de>
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XEarth is a program that draws a constantly changing picture of the earth on
your backdrop.  Its usual behaviour is to show you where the sun is shining
brightest; however, you can fix it on one spot and watch the sunlight go over
that, or tell it to show random points instead.

This document will only tell you information relevant to the Acorn port of
XEarth; the full list of options is contained in the 'ManPage' document,
which is the Unix manual page for XEarth

     Desktop operation
     -----------------

The Acorn port tries to mimic the X version pretty closely; if you start
xearth normally, it will initialise itself as a WIMP task and render to the
Pinboard every five minutes as expected.  To force XEarth to re-render, you
can click adjust on the icon-bar icon.

When running as a WIMP task, the size and colour depth of the image will be
fixed to the current screen mode.  Because it takes a little time to render
an image, if you change mode, you'll see a bodged image (i.e. scaled up or
down) for a few seconds while XEarth renders one for the new screen size.

For the moment, if you want to change the rendering options, you'll have to
edit the !Run file; consult the ManPage document for what does what.

     Command-line operation
     ----------------------

For command-line output, as well as the -gif and -ppm options, there is a
-sprite option which tells XEarth to render to an Acorn sprite.  By default
this is a 24-bit ('true colour') sprite, but you can specify the -ncolors
option to change this: using -ncolors when rendering to a sprite can take
values from 2-255, which will render to a dithered 8-bit sprite, or 32K / 16M
which will render to 16-bit and 24-bit colour depths respectively.

Options which aren't relevant to the Acorn port are -fork, -gamma, -twopix,
-mono, -nice and -display.  -labels and -markers are currently unimplemented,
but...

      I'm working on it!
      ------------------

I take no responsibility for bugs, problems, random summonings of Satan or
whatever other oddities this program causes with your machine.  But I use it,
so it must be safe... here's my list of stuff that wants doing:

   * get it to read the map data from a file rather than loading it all
       into memory;
   * finish the options window for full WIMPification;
   * -label / -markers options;
   * fix the explosion if you change modes too quickly;
   * direct poking of the Earth image to the pinboard (grotty, but should
       stop all that tedious messing about with temporary files).

The latest version should be available from somewhere on
       
       <http://www.soup-kitchen.demon.co.uk>

so look there for updates before complaining about stuff ;-)

      Version history
      ---------------

0.01     was terrible, but I'd hardly looked at it.

0.10     is better.

      License
      -------

See the copyright section of the ManPage for full details; as far as I'm
concerned it's basically all free free free, source and all.

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Problems, suggestions etc. to me, Matthew Bloch: email <mattbee@eh.org>
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