Evolver Manual

This document tells you how to install and run Evolver, the computer artist. You will need a Java 2 supported platform (Linux, Mac OS X, Windows, Solaris) and a relatively fast computer (Pentium II or better) with 100MB of RAM. You may want to read the end of the Evolver Paper for more information on each of the GUI windows.

Note: Evolver was designed as a research tool, and I wrote all of the code from scratch in under a month. Although it has an attractive user interface and will run on many platforms, it is not a commercial product. Installation requires some familiarity with Java, and it is not unusual for the program to crash or perform poorly under stressful circumstances.

Download Evolver

Download evolver.zip. You will need to uncompress this using a tool like PKZip, WinZIP, or gzip. This file contains a large number of files of the following types: If you are just interested in looking at the source, you can stop here. If you want to run Evolver, keep reading.

Install Java

Evolver is written in Java for the 1.3 ("Java 2") API. Evolver does not run in a web browser. Most web browsers don't support version 1.3 of the Java API and Evolver is designed to run as a stand alone application anyway. So, you need to install a Java runtime in order to run Evolver.

You can download Java 1.3 from Sun's site. They support Solaris, Linux, and Windows. If you are running Mac OS X, you already have Java 1.3 installed.

Run Evolver

Once you've installed Java 1.3 and downloaded Evolver, you're ready to go. Windows users can launch Evolver by typing "evolver" in the Evolver directory. Users on other platforms must type java -Xincgc -Xmx100M Evolver. This command line runs Evolver with a large heap size and incremental garbage collection, both of which improve performance.

Evolver takes a while to load because it opens many windows and generates a series of images. If you want to play an animation, you can launch the animation player separately using java -Xincgc -Xmx100M AnimationPlayer animationname.anm. To just run the Behavior Viewer, use java -Xincgc -Xmx100M BehaviorViewer.

Evolving Images

When Evolver loads, it displays sixteen images in the main window. These are randomly generated. Select the images you like best by clicking on them once. If you want to see an image animated, or want a closeup, drag the image from the main Evolver window onto the Behavior Viewer.

When you have a set of images you like, press the organge "evolve" button in the lower right corner. Evolver will process for a while, then show you a new set of sixteen images that are combinations of the originals. Select the ones you like and evolve again.

At any point, you can press the red "reset" button to get a completely random generation. In addition to dragging images from the Evolver window, you can drag them onto the window. Almost any image in Evolver can be dragged to replace any other image. The large picture in the center of the Morph window is one exception. Don't drag it or you will crash the program.

Saving Images

Drag the image you want to save to the Behavior Viewer.

You can make a screenshot using your operating system's built in mechanism. On Windows, press the Print Screen button, then open a graphics program like Paint Brush or PhotoShop and paste. You may want to use the resolution drop down box to render a large version of the image before taking a screen shot.

To save an expression for later rendering or further evolving, copy the text out of the green box in the Behavior Viewer and save it using a text editor. To load a saved expression, double click on the green window, then paste your saved expression in and press the check button.

Making animations

You can string animations together using morphs to create a longer, more complicated animation. Drag images onto the Animation Editor, then type in the text boxes to change the length of each sequence. Animations can't be viewed in Evolver. You have to run the AnimationPlayer separately ("animation.bat").

Optikal.anm is a sample animation. You can play it by typing animation Optikal.anm. It is designed to be synchronized with optikal.s3m, a ScreamTracker III file you can play in WinAMP.

Evaluating Expressions

You may want to make up expressions on your own, using the Evolver Language (EL) directly instead of evolving expressions. The Behavior Viewer can be used for this purpose. Double click on the green text box and type in an expression. Press the green check button to evaluate your expression. If you typed something illegal, a popup may appear, or the program may crash. I recommend editing in a code editor like Emacs and pasting expressions into the window.

You can launch the Behavior Viewer by itself by running "editor.bat". This saves you the time of waiting for Evolver to load. Note that you need to resize the Behavior Viewer to see the filter diagram on the right side.

Morgan McGuire matrix@acm.org