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dbal presents ...



See an updated and more interesting version at

An infestation of unfriendly spiders.

Click the Run button to start.
Click the Reset button and the Run button to restart.

Spiders fight for territory and some die when they
fight. When a spider dies, it lays motionless for the
duration of the run and is ignored by the remaining
live spiders.

All live spiders reproduce when the user clicks the
world, each live spider producing one offspring.

4971 views / 595 in the last 7 days

Tags: simulation

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A new version of this scenario was uploaded on Fri Jul 04 17:51:03 UTC 2008


Tried to run this as a 450x450 world, but that is apparently too large to run online because it is not all visible. Note, however, that it is all visible when exported and run as a local applet. Will cut back the overall size and see what happens. It looks like the online size limit is about 405 wide by 225 high.
A new version of this scenario was uploaded on Fri Jul 04 18:27:42 UTC 2008


Seems to fit and run OK for a world size equal to 400 pixels wide and 240 pixels high with a one-pixel cell size. However, this is much smaller overall than the Wave scenario. The difference may be that the cell size may be larger in the Wave scenario. Maybe the upper limit on size is based on the number of cells and not the actual number of pixels - just a guess on my part.


I just tried testing this with a few other scenarios, and the problem is that the size of the applet is not updated after the first time the scenario is submitted. I have added the it to our bug tracking system.


That means that for now, the size of a scenario submitted to the Gallery cannot be changed. A work-around is to change the title - this will create a new scenario. However, the "I like it" votes and the comment history would be lost. We'll see that we fix this for the next release.


It should be fixed now, but I haven't yet tested the fix. Dick, maybe you would like to try it now?
A new version of this scenario was uploaded on Mon Jul 07 23:51:18 UTC 2008


Yes, the problem with changing the size of the scenario after the first upload is fixed. Thanks, Dick Baldwin Free online programming tutorials:
A new version of this scenario was uploaded on Tue Jul 08 17:08:53 UTC 2008

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