Vector4

type alias Float4 =

Vec4 Float

type alias Vec4 a =

( a, a, a, a )

fromV3 : Vec3 a -> a -> Vec4 a

fromV3 (1,2,3) 1 == (1,2,3,1)

setX : a -> Vec4 a -> Vec4 a

setY : a -> Vec4 a -> Vec4 a

setZ : a -> Vec4 a -> Vec4 a

setW : a -> Vec4 a -> Vec4 a

getX : Vec4 a -> a

getY : Vec4 a -> a

getZ : Vec4 a -> a

getW : Vec4 a -> a

map : (a -> b) -> Vec4 a -> Vec4 b

map (\x -> x^2) (1,2,3,4) == (1,4,9,16)

map2 : (a -> b -> c) -> Vec4 a -> Vec4 b -> Vec4 c

map2 (<) (2,1,4,2) (3,2,1,6) == (True, True, False, True)

foldl : (elem -> acc -> acc) -> acc -> Vec4 elem -> acc

foldl (\elem acc -> acc + elem^2) 0 (2,4,1,2) == 25

foldr : (elem -> acc -> acc) -> acc -> Vec4 elem -> acc

foldr (::) [] (1,2,3,5) == [1,2,3,5]

add : Float4 -> Float4 -> Float4

v + w

add (2,4,1,-2) (3,-6,2,1) == (5,-2,3,-1)

sub : Float4 -> Float4 -> Float4

v - w

sub (4,6,1,2) (3,-1,-4,4) == (1,7,5,-2)

negate : Float4 -> Float4

-v

negate (2,-1,5,1) == (-2,1,-5,-1)

scale : Float -> Float4 -> Float4

a*v

scale (3/2) (4,2,6,10) == (6,3,9,15)

divideBy : Float -> Float4 -> Float4

v/a

divideBy (3/2) (3,12,6,9) == (2,8,4,6)

dot : Float4 -> Float4 -> Float

v dot w

The dot product of two vectors. Also called scalar product or inner product.

It links the length and angle of two vectors.

v dot w = |v|*|w|*cos(phi)

dot (1,2,2,3) (3,3,2,2) == 1*3 + 2*3 + 2*2 + 3*2 == 19

length : Float4 -> Float

The length of a vector. Also known as magnitude or norm.

|v| = sqrt(v dot v)

length (2,4,1,2) == sqrt (2^2+4^2+1^2+2^2) == 5

lengthSquared : Float4 -> Float

The squared length. This is cheaper to calculate, so if you only need to compare lengths you can use this instead of the length.

|v|^2 = v dot w

lengthSquared (3,4,1,2) == 3^2+4^2+1^2+2^2 == 30

normalize : Float4 -> Float4

Normalizes a vector. This will give you a unit vector (e.g. with length 1) in the same direction as v.

v/|v|

normalize (2,4,1,2) == (2/5,4/5,1/5,2/5)

directionFromTo : Float4 -> Float4 -> Float4

A unit vector pointing from v to w

(w - v)/|w - v|

directionFromTo (5,1,2,4) (7,5,3,6) == (2/5,4/5,1/5,2/5)

distance : Float4 -> Float4 -> Float

Calculates the distance from v to w.

|v - w| = |w - v|

distance (7,5,3,6) (5,1,2,4) == 5

distanceSquared : Float4 -> Float4 -> Float

The squared distance. This is slightly faster.

|v - w|^2

distanceSquared (3,0,2,1) (0,2,4,1) == 17

angle : Float4 -> Float4 -> Float

The angle between two vectors. The angle is in radians.

acos((v dot w)/(|v|*|w|))

angle (-1,-1,2,0) (2,2,2,0) == pi/2    -- or 90°

Zinggi/elm-webgl-math/1.0.2

Vector4

Modules