Interactions

Interactions		back
In this chapter, the behaviour of an individual depends on the behaviour of the others. A leader may exist, but is not necessary. Leadership can change, be seperated between different individuals (who might not be aware of their own ledership) or be invisible. A particularly interesting case is a leader seeking for accordance with the ones he is leading.

BIRDS

Birds are able to fly in a flock moving so harmonically that it looks like one single large bird.

Craig Reynolds described the behaviour of each animal composing of four elements in 1986:

1. Follow the leader (which may change).
2. Keep distance to the other birds.
3. Head to the centre of the flock.
4. Adapt your speed to the one of the others.

In this applet you can influence the relative weight of each of these four components (the starting values have arbitrarily been set as 100 : 100 : 100 : 100).

See how the outer appearance of the swarm changes!

	ONE PERSON
For creating a virtual society, I have started with programming persons. This is my first finger exercise on this way. It can just watch the mouse cursor and follow it.

	OUT OF THE WAY
The next step for the virtual persons is to learnt to interact with each other. When two of them meet, they check if their future postions are colliding or not. If this is the case, they decide in function of their own and the other's orientation if they turn to the right or to the left. Just play a little around with this demonstration.

JOSTLE

You can watch some characters walking around on a square trying not to collide with each other. They belong to three different groups with a different behaviour, symbolized by different colours.

Members of the first group change their direction when they meet somebody else, the sense of the change depending from the orientation of the two.

In the second groups, the men have the priority. When they meet a woman, they just keep on walking ahead, meanwhile the woman tries to get out of his way.

In the third group, it is the other way round, the men letting the priority to the women.

By clicking the correspondant buttons, you can bring members of the different groups into the game or remove them by directly clicking on the characters themselves.

Just watch how they get along with each other!

	TRIBES
Here, the square is a torus, which means that the edges are linked. This makes it limited and endless at the same time. Each character adapts his walking direction to the member of his own family which is located next to him.

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