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If you add to vectors together, the resulting vector is the equivalent of stacking the vectors end to end. The maths behind it is simple, just add the x positions of each vector together and then add the y positions together. Adding vectors together can be used to simulate simple physics like the effect of wind or gravity, so for every step forward a game character might have a wind vector added to their movement vector. If a character in a game jumps while moving forward, then we also want to add the vectors of the upward movement with the forward motion, and then in reverse when they fall back down.
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Normalising
A normalised vector or a unit vector has had its magnitude set to one, with the direction left unchanged. A unit vector shows us a direction and can be easily scaled by any value.
Finding the magnitude
You can find the magnitude (the length) using Pythagorean theorem:(Diagram 7. sqrt(x^2 + y^2. A magnitude and unit vector can easily be recombined to create
c = (4, 5)
sqrt(4^2 + 5^2))
PVector
Processing has a vector class called ‘PVector‘, which can be two or three dimensions. Basic vector maths are included in a number of methods of the PVector class, so processing can do all the hard work for you.
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