A java applet that can be used to generate patterns and explore symmetry is available for
use. In particular, "edge limit" patterns, "center limit" patterns and patterns where
the foreground and background are reversible may be generated. Such patterns were made
famous by the Dutch artist M. C. Escher.
A quick understanding of the program's capabilities may be obtained by working the short
tutorial included in the help file.
The program consists of a Java applet and two supporting PHP scripts.
help file is included with the program. This file describes in detail the capabilities of the program
and how to use it.
The java applet is called from an html file (see Patterns.html) using the following code:
<applet code="Patterns.class" archive="Patterns.jar" width=1034 height=804>
<param name=Server value="bprentice.webenet.net">
<param name=Directory value="Patterns">
<param name=ReadFile value="pattern">
<param name=WriteFile value="pattern">
The four 'param' lines define the applet options. The value of 'Server' is the address
of your server. If you install the program in a subdirectory of your public_html directory, set the value of 'Directory' to that subdirectory otherwise set the value of 'Directory' to "".
The program saves patterns in a pattern file. This file contains a special header.
For security reasons, the program will not create this file and will only append patterns
to an existing file containing this special header. The file is normally called pattern
and is created by making a copy of the file called header.
The values of 'ReadFile' and 'WriteFile' should normally be set to the same value pattern.
If you wish to edit a pattern file, however, set the value of 'ReadFile' to an existing
file and set the value of 'WriteFile' to the name of a new copy of the header file.
To install the program do the following:
Download Patterns.zip and unzip it using
WinZip. This will provide you with copies of all
- Decide on a directory to hold your program. This will typically be your
public_html directory or one of its subdirectories.
- Edit the Patterns.html file to reflect your needs paying particular attention to the
four 'param' lines which define your options.
- Upload the 'jar' file, the two php files, all the 'gif' files, all the 'html' files, and the
header file to your selected directory.
- Make a copy of header and call it pattern (or the value of the WriteFile parameter if
you changed this parameter).
- Test your program.
The following files are included in Patterns.zip.
You may examine and try a
The Java source code for Patterns together with the source code for the supporting PHP scripts is included in Patterns.zip
The format of the picture file is described
- The Infinite World of M. C. Escher - Harry N. Abrams, Inc., New York 1984.
- An Implementation of the Henderson Picture Language - Lisp: A Language for
Stratified Design - By Harold Abelson and Gerald Jay Sussman - Byte February 1988
Please take a look at my
and the stand alone version of my
This program was written by Brian Prentice who may be contacted at
355, So 8th St., #26
Coos Bay OR 97420