4 Jun ’08

Choice-based wandering

I've written about different wandering algorithms in one of the sidetrack posts, but now it is time to decide and design an algorithm by which the craas move around. There's several that spring to mind. The first, and perhaps most well-known one is to separate the field of vision of a craa in three regions (left, right, forward), and let it navigate to the region which is the most attractive.



Extensions of this three-field method would include more fields (closeby, far away), so that a tiger far away isn't taking precedence over quenching the craas' thirst at this water pool right now. A simplification of the fields algorithm would be to consider a single, circular field, and sum up all the vectors from all the impulses to obtain a direction.

There is different ways to sum up. We could weight different impulses based on the strength of the emotions associated with them, and on the distance they are away from us. More complicated, you could also weight them on whether or not they are expected (using the craas memory to create an image of what is expected) and give special weight to unexpected things. The latter puts us into a little bit of trouble though.. what if a craa expects a lion to charge him and thus pays no attention anymore.

Summing impulses can put you into a classical bit of trouble called Buridan's ass, which actually occurs in reality (although not neccesarily in donkeys), so we will have to see if the artifacts of a summing system are acceptable.

One thing I do want is that next to perhaps weighting based on distance, weighting based on the current needs of the craa. How needs are managed and created will be the topic of another post.