glsl.ml

type scalar = float
type z = private Z type 'a s = private S
type _ t =
  | Scalar: scalar -> 'any t
  | Vec2: {x:float;y:float} ->  z s t
  | Vec3: {x:float;y:float;z:float} -> z s s t

let (+) (type dim) (x: dim t) (y:dim t) : dim t =
  match x, y with
  | Scalar a, Scalar b -> Scalar (a +. b)
  | Scalar s, Vec2 {x;y} -> Vec2{x=x+.s;y=y+.s}
  | Vec2 {x;y}, Scalar s -> Vec2{x=x+.s;y=y+.s}
  | Scalar s, Vec3 {x;y;z}  -> Vec3{x=x+.s;y=y+.s;z=z+.s}
  | Vec3 {x;y;z}, Scalar s  -> Vec3{x=x+.s;y=y+.s;z=z+.s}
  | Vec2 a, Vec2 b -> Vec2{ x= a.x +. a.x; y = a.y +. b.y }
  | Vec3 a, Vec3 b -> Vec3{ x= a.x +. a.x; y = a.y +. b.y; z = a.z +. b.z }