module Diagrams.ThreeD.Deform
  ( parallelX0, perspectiveX1, facingX
  , parallelY0, perspectiveY1, facingY
  , parallelZ0, perspectiveZ1, facingZ
  ) where

import           Control.Lens

import           Diagrams.Deform
import           Diagrams.TwoD.Deform

import           Linear.V3
import           Linear.Vector

-- | The parallel projection onto the plane z=0
parallelZ0 :: (R3 v, Num n) => Deformation v v n
parallelZ0 :: forall (v :: * -> *) n. (R3 v, Num n) => Deformation v v n
parallelZ0 = forall (v :: * -> *) (u :: * -> *) n.
(Point v n -> Point u n) -> Deformation v u n
Deformation (forall (t :: * -> *) a. R3 t => Lens' (t a) a
_z forall s t a b. ASetter s t a b -> b -> s -> t
.~ n
0)

-- | The perspective division onto the plane z=1 along lines going
--   through the origin.
perspectiveZ1 :: (R3 v, Functor v, Fractional n) => Deformation v v n
perspectiveZ1 :: forall (v :: * -> *) n.
(R3 v, Functor v, Fractional n) =>
Deformation v v n
perspectiveZ1 = forall (v :: * -> *) (u :: * -> *) n.
(Point v n -> Point u n) -> Deformation v u n
Deformation forall a b. (a -> b) -> a -> b
$ \Point v n
p -> Point v n
p forall (f :: * -> *) a.
(Functor f, Fractional a) =>
f a -> a -> f a
^/ (Point v n
p forall s a. s -> Getting a s a -> a
^. forall (t :: * -> *) a. R3 t => Lens' (t a) a
_z)

facingZ :: (R3 v, Functor v, Fractional n) => Deformation v v n
facingZ :: forall (v :: * -> *) n.
(R3 v, Functor v, Fractional n) =>
Deformation v v n
facingZ = forall (v :: * -> *) (u :: * -> *) n.
(Point v n -> Point u n) -> Deformation v u n
Deformation forall a b. (a -> b) -> a -> b
$
  \Point v n
p -> let z :: n
z = Point v n
p forall s a. s -> Getting a s a -> a
^. forall (t :: * -> *) a. R3 t => Lens' (t a) a
_z
        in  Point v n
p forall (f :: * -> *) a.
(Functor f, Fractional a) =>
f a -> a -> f a
^/ n
z forall a b. a -> (a -> b) -> b
& forall (t :: * -> *) a. R3 t => Lens' (t a) a
_z forall s t a b. ASetter s t a b -> b -> s -> t
.~ n
z