{-# OPTIONS_HADDOCK hide #-}
{-# LANGUAGE BangPatterns #-}
module Graphics.WorldTurtle.Internal.Coords
( module GPoint
, module GArithmetic
, module GVector
, module GAngle
, lerp
, normalizeHeading
) where
import Prelude hiding ((-), (+))
import qualified Prelude as P
import Graphics.Gloss.Data.Point as GPoint
import Graphics.Gloss.Data.Point.Arithmetic as GArithmetic
import Graphics.Gloss.Data.Vector as GVector
import Graphics.Gloss.Geometry.Angle as GAngle
lerp :: Float
-> Point
-> Point
-> Point
lerp :: Float -> Point -> Point -> Point
lerp !Float
l !Point
a !Point
b = let (!Float
ux, !Float
uy) = (Float
1 Float -> Float -> Float
forall a. Num a => a -> a -> a
P.- Float
l) Float -> Point -> Point
`mulSV` Point
a
(!Float
vx, !Float
vy) = Float
l Float -> Point -> Point
`mulSV` Point
b
!n :: Point
n = (Float
ux Float -> Float -> Float
forall a. Num a => a -> a -> a
P.+ Float
vx, Float
uy Float -> Float -> Float
forall a. Num a => a -> a -> a
P.+ Float
vy)
in Point
n
normalizeHeading :: Float -> Float
normalizeHeading :: Float -> Float
normalizeHeading Float
0 = Float
0
normalizeHeading Float
f = let (Int
n, Float
b) = Float -> (Int, Float)
forall a b. (RealFrac a, Integral b) => a -> (b, a)
properFraction Float
f :: (Int, Float)
f' :: Float
f' = Int -> Float
forall a b. (Integral a, Num b) => a -> b
fromIntegral (Int
n Int -> Int -> Int
forall a. Integral a => a -> a -> a
`rem` Int
360) Float -> Float -> Float
forall a. Num a => a -> a -> a
P.+ Float
b
in if Float
f' Float -> Float -> Bool
forall a. Ord a => a -> a -> Bool
<= Float
0 then Float
f' Float -> Float -> Float
forall a. Num a => a -> a -> a
P.+ Float
360 else Float
f'