why use vectors?

vectors are useful for any game. they are really useful in 3d games.
i will show you 2d vectors first.
a vector is a line from 0,0 to any other location. it has vector components, which are the horizontal distance, and vertical distance. it also has a magnitude, which is the length.

you would normally move an object towards another like this...

Code:

direction=point_direction(x,y,other.x,other.y);

this is how you do it using vectors.
First, you need to get the components. i will use hspeed and vspeed because it will be more convenient.

Code:

hspeed=x-other.x;
vspeed=y-other.y;

Second, you need to get the magnitude. you can use point distance but that won't work when you get into 3d. so i will use sqr() and sqrt(), which is square and square root.

Code:

var m;
hspeed=x-other.x;
vspeed=y-other.y;
m=sqrt(sqr(hspeed)+sqr(vspeed));

Next, you need to normalize the components. normalizing scales the vector to a length of 1.

Code:

var m;
hspeed=x-other.x;
vspeed=y-other.y;
m=sqrt(sqr(hspeed)+sqr(vspeed));
hspeed/=m;
vspeed/=m;

so now, the object will move towards the other object at a speed of 1. i can set the speed by changing the magnitude before i normalize.

Code:

var m;
hspeed=x-other.x;
vspeed=y-other.y;
m=sqrt(sqr(hspeed)+sqr(vspeed))/8;
hspeed/=m;
vspeed/=m;

the object will move at a speed of 8 now.
you can't use point_direction in 3d, so vectors come in handy.
this is exactly the same process when in 3d, i just make a z and a zspeed variable for the object.

Code:

var m;
hspeed=x-other.x;
vspeed=y-other.y;
zspeed=z-other.z;
m=sqrt(sqr(hspeed)+sqr(vspeed)+sqr(zspeed))/8;
hspeed/=m;
vspeed/=m;
zspeed/=m;

i will go back and improve this if anyone is confused.

What are the advantages of using vectors in 2D games? Why is it any better?

-js1210- wrote:What are the advantages of using vectors in 2D games? Why is it any better?

not much advantage in 2d games, unless your making lots of complicated code. like for bouncing a ball of a line.

i didnt read that fully, are there vectors in 3d games (to clear up for others, to lazy to explain anything)

Interesting and seemingly complicated, but I think I understand. I'll make sure I look at this again whenever I start my transition into 3D.