Skeleton.hs

module Graphics.LambdaCube.Skeleton where

import Graphics.LambdaCube.Types

import Data.Map (Map)
import Data.Tree
import qualified Data.Vector as V

data Bone = Bone
    { bnPosition :: Vec3
    , bnRotation :: U
    }
    deriving Show

data KeyFrame = KeyFrame
    { kfPosition :: Vec3
    , kfRotation :: U
    , kfTime     :: FloatType
    }
    deriving Show

data Animation = Animation
    { anTracks  :: V.Vector [KeyFrame]
    , anLength  :: FloatType
    , anName    :: String
    }
    deriving Show

data Skeleton = Skeleton
    { skBones       :: V.Vector Bone
    , skBoneTree    :: Tree Int
    , skAnimations  :: Map String Animation
    }
    deriving Show

data PoseData = PoseData
    { pdJointMatrix         :: Proj4
    , pdInverseBindMatrix   :: Proj4
    , pdWorldMatrix         :: Proj4
    , pdSkinningMatrix      :: Proj4
    }

-- FIXME: remove Data.Vec.LinAlg.Transform3D dependency
{-
mat33ToMat44 (a:.b:.c:.()) = (h a):.(h b):.(h c):.(0:.0:.0:.1:.()):.()
  where
    h x = Vec.snoc 0 x

poseData :: Skeleton -> Animation -> FloatType -> Vector PoseData
poseData s a t = visit Nothing idPD $ skBoneTree s
  where
    bones = skBones s
    idPD = V.replicate (V.length $ skBones s) $ PoseData idMat idMat idMat idMat
    idMat = Vec.identity
    visit p v (Node i []) = f p i v
    visit p v (Node i l) = foldl' (visit $ Just i) (f p i v) l
    f p i v = v // [(i,PoseData jm ibm wm sm)]
      where
        b = bones V.! i
        rot = mat33ToMat44 $ quatToMat $ bnRotation b
        trans = translation $ bnPosition b
        jm = rot `multmm` trans
        ibm = invertMat44 jm
        wm = pwm `multmm` jm
        sm = idMat
        pwm = maybe idMat (\n -> pdWorldMatrix $ v V.! n) p

-}