Document: SCL: An Artificial Chemistry in Swarm

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6.1 Who needs an Observer?

The standard Swarm example applications enforce a strict distinction between an ``observer'' and the ``model'' itself. The idea is to facilitate easier switching between versions which operate in ``batch'' mode (with no user interaction) and versions which operate in ``GUI'' mode (with user interaction).

This is a very reasonable and useful strategy.

However, in the case of SCL I knew that I did not want the facility to operate in ``batch''mode--it was intended and designed strictly as an interactive application. Furthermore, I found that the attempt to maintain the flexibility of supporting both batch and interactive modes made the application more complex, and also made the implementation of user interaction more cumbersome. Therefore I abandoned the observer/model distinction, and rationalised the program accordingly. This is not an intrinsically better or worse approach; it is simply another alternative that some users may find of interest.



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Document: SCL: An Artificial Chemistry in Swarm

Copyright © 1997 All Rights Reserved.
Timestamp: Tue Dec 31 19:40:38 GMT 1996

mcmullin@eeng.dcu.ie