4.3 Boids Flocking

Boids Flocking

Then boids algorithm also know as boids flocking, is an artificial life motion of how birds flock together and how fish swim in schools. "It was based on three dimensional computational geometry of the sort normally used in computer animation or computer aided design."(8) 
I have used a quote from Craig Reynolds who is the founder of boids flocking because here he mentions this technique is used in computer animation or computer aided design, well a good example of boids being used in a game is from this screen shot from Far Cry on PS4.

(9)
Now you can ask yourself what is the point of adding a large flock of birds randomly flying around, well to answer that question, first we need to talk about how boids work.








When it comes to boids flocking, the first segment of three is the alignment, alignment is the behaviour that will set an agent to line up with the other agents in the vicinity, for example if you have a fish swimming around on its own and is going into a different direction to the other fish, the the line fish joins the other fish, the alignment will correct the fish's path and align it with the rest of the fish in the flock so they are all facing in the same direction.

Next is cohesion, this behaviour will cause the agent (fish) to aim towards the middle of the flock (centre of mass), This is the centre of which is created by the radius of the flock. Finally is the separation, this is when the agent\fish will behave in away which will steer away from the others in the vicinity.

So now we have a basic understanding of how it works and the three main entities that make up boids flocking, we need to introduce why its used. Now the term "flocking" is used to mimic the movement of a flock of birds, its used in real world games such as Far Cry, Grand Theft Auto and Assassins Creed.

"Often in video games, nonplayer characters must move in cohesive groups rather than independently. Let’s consider some examples. Say you’re writing an online role-playing game, and just outside the main town is a meadow of sheep. Your sheep would appear more realistic if they were grazing in a flock rather than walking around aimlessly."(10) 

So Seemann and Bourg like to reflect that boids flocking is to make the game look more realistic for the user experience, yes they have mentioned its purpose but I feel its more that just a few sheep eating in a field. As a gamer myself, the ultimate high when playing a video game is to feel like your really in the game itself, to be drawn into that other world we wish we could live in. In a free roam world you may not be always be paying attention to the sky, but as you are walking down street in GTA, to catch a flock of birds in the corner of your eye flying in to and back out of the scene, really makes you feel like your really in the game.