Simple 2d vector class. Public domain :)

vector2.coffee

class Vector2 
	@fromArray: (a) -> new Vector2 a[0], a[1]
	constructor: (x, y) -> @set x, y
	set: (x, y) -> @[0] = x; @[1] = y; @x = x; @y = y; @
	clone: -> new Vector2 @x, @y
	add: (v) -> @clone().iadd v
	iadd: (v) -> @set @x+v.x, @y+v.y
	sub: (v) -> @clone().isub v
	isub: (v) -> @set @x-v.x, @y-v.y
	muls: (s) -> @clone().imuls s
	imuls: (s) -> @set @x*s, @y*s
	len: -> Math.sqrt(@x*@x + @y*@y)
	norm: -> @clone().inorm()
	inorm: -> len = @len(); @set @x / len, @y / len; @
	normal: -> @clone().inormal()
	inormal: -> @set(@y, -@x).inorm()