In this project, we explore an example of a boids simulation — a simulation aiming to mimic the flocking behaviour of birds or the creation of schools of fish.
Boids (bird-oid objects) are individual autonomous agents following a set of simple predefined rules: separation, alignment and cohesion.
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Separation
A boid steers away from other boids nearby to avoid crashing into them
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Alignment
A boid steers in the average direction of the boids surrounding it
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Cohesion
A boid steers towards the average position of the nearby boids
When each of the agents abides by these rules, we can notice a pattern of behaviour emerging from all of the boids. We call that the emergent behaviour. In this case, the emergent behaviour is the creation of flocks of individual boids.
Refer to the design document.
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Go (installation instructions)
Tested with go1.17.3 for the linux/amd64 platform.
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Pixel (GitHub)
A hand-crafted 2D game library in Go.
To install all dependancies simply run
go get ./...
while inside of the project directory. If that doesn't work, to download and install the Pixel package manually, execute
go get github.com/faiface/pixel
in your terminal window.
First, build the project by executing
go build .
Then, to run the project
./boids
in your terminal.
To change the variables used for the simulation, pass their values to the executable by using the relevant command-line arguments:
./cs50 -a 4.0 -c 2.5 -s 3.0 -n 100
The above example sets the alignment factor to 4.0, the cohesion factor to 2.5, and the separation factor to 3.0. The last flag specifies that a hundred boids is going to be simulated.
To move the camera view around, simply click&drag using your mouse (similarly to Google Maps). You can also zoom in using your scroll wheel.
To quit the simulation and exit the program, press the Esc key.
A big thank you to the creators of the Go language, the Pixel library, as well as Craig Reynolds and his work on boid simulations.