VIEWEPS documentation

SLAC 18 April 1995

VIEWEPS is a tool that enables collections of encapsulated Postscript (eps) files to be made available on the web. It provides facilities for:

Creating thumbnail GIF images from the eps files
Automatic translation of eps files into plain postscript, GIF or JPEG, at the request of the user.
Facilities for users to request hard copy (print) versions of eps files.

This facility is used to make several collections of eps figures available at SLAC.

Setting up an image archive

ViewEPS requires that the directories containing an EPS archive be set up in a stylized fashion, as illustrated below: Each archive can contain an arbitrary number of eps collections (e.g. collection1, collection2 in the above diagram). Within each collection one directory (named eps) must contain the source eps files, and a second directory (named thumbnail) must contain the thumbnail images created from the eps files. Configuration files can be placed in each collection directory, and will override the default configuration files set up by the maintainer of vieweps. The configuration files can be used to control which printers will appear in the list of printers, and to control the text that will appear at the top and bottom of each page generated by vieweps.

Each eps archive requires an entry in the web server configuration file. For the above archive the line would be of the form:


Map   /a/b/c/figure/* /cgi-bin/vieweps/*

Creating Thumbnail Images

To create the thumbnail images from the eps images, cd to the directory containing the eps files, and issue the command:

   tna *.eps

(At SLAC the tna files lives in /usr/local/www/bin, so you will need to make sure that directory is included in your unix PATH).

Any time you change one of the eps files, or add a new one, reissue the above command, and it will process only those files that have changed since it was last run. If for any reason you want to regenerate all of the thumbnail images just issue the commands:

   rm ../thumbnail/*.gif
   tna *.eps

Setting up configuration files

The VIEWEPS package reads several configuration files which control its oepration. You can override any of the default configuration files for a particluar eps collection by placing a modified copy of the relevant configuration file in the root directory for the collection (e.g. /a/b/c/figure/collection1 in the above diagram).

See the documentation below for details of the configuration files.

Describing the files

By default the list of eps files for a particular collection will show the name of each file in the collection. You can add a more explicit description of each file by creating a file called index in the root directory of a collection (see example). This file should contain one line for each eps file. Each line contains two colon delimited fields, which contain:

The name of the eps file (without the trailing .eps)
The description of the file, which may include HTML markup.

Implementation

The VIEWEPS package consists of the following files:

vieweps: A cgi script which must be installed in the cgi-bin directory of your web server. This is a perl script which produces the web pages seen by vieweps users.
tna: A simple script which is used to generate the thumbnail images. At SLAC this is kept in /usr/local/www/bin
tn: A script which is used by tna. At SLAC this is kept in /usr/local/www/bin

In addition you will need the epsfix utility written by Ray Cowan, as well as ghostscript and various parts of the pbmplus package. To create JPEG images you will also need the cjpeg utility from the Independent JPEG group.

Configuration files

print.conf

Controls what printers postscript can be sent to (See example). The file contains one line per printer. Each line contains three colon delimited fields. These fields should contain:

The printer name
The command to be used to print the document. This command should expect to read the postscript to be printed as STDIN and generate any error messages on STDOUT.
A description of the printer. May contain HTML markup.

head.html

Text to appear before the list of eps files. (See example)

tail.html

Text to appear after the list of eps files. (See example)

tail2.html

Text to appear after the list of formats for a specific eps image. (See example)

tail3.html

Text to appear after the list of printers. (See example)

tail4.html

Text to appear after a file has been printed. (See example)

The source code

Is available here.

TonyJ