Game Development Reference
In-Depth Information
What are vectors?
First, let's do a quick refresh on vectors and the way you can use Cocos2d-x to deal with
them.
So what is the difference between a vector and a point? At first, they seem to be the same.
Consider the following point and vector:
• Point (2, 3.5)
• Vec2 (2, 3.5)
The following figure illustrates a point and a vector:
In this figure, they each have the same value for
x
and
y
. So what's the difference?
With a vector, you always have extra information. It is as if, besides those two values for
x
and
y
, we also have the
x
and
y
of the vector's origin, which in the previous figure we can
assume to be point (0, 0). So the vector is
moving
in the direction described from point (0,
0) to point (2, 3.5). The extra information we can derive then from vectors is direction and
length (usually referred to as magnitude).
