472 lines
17 KiB
Haskell
472 lines
17 KiB
Haskell
{-# LANGUAGE TupleSections #-}
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{-# LANGUAGE BangPatterns #-}
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{- |
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Basic helpers.
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Consider splitting. -}
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module Dodge.Base
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( module Dodge.Base
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, module Dodge.Base.You
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, module Dodge.Base.NewID
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, module Dodge.Base.WinScale
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, module Dodge.Base.Window
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, module Dodge.Base.Coordinate
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, module Dodge.Base.Collide
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) where
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import Dodge.Data
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import Dodge.Base.WinScale
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import Dodge.Base.NewID
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import Dodge.Base.Coordinate
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import Dodge.Zone
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--import Dodge.Zone.Data
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import Dodge.Base.Window
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import Dodge.Base.Collide
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import Geometry
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--import Picture
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import qualified IntMapHelp as IM
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import FoldableHelp
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import qualified FoldlHelp as L
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import Dodge.Base.You
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import Control.Lens
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import Data.Monoid
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import Data.Maybe
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--import Data.Bifunctor
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--import qualified Data.IntSet as IS
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--import qualified Data.Set as S
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{- | Implementation copied from
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- https://hackage.haskell.org/package/utility-ht-0.0.16/docs/src/Data.List.HT.Private.html#takeUntil
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-}
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takeUntil :: Foldable t => (a -> Bool) -> t a -> [a]
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takeUntil p = foldr (\x xs -> x : if p x then [] else xs) []
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decreaseToZero :: Int -> Int
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decreaseToZero = max 0 . subtract 1
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decreaseToNothing' :: (Num a, Ord a) => Maybe' a -> Maybe' a
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decreaseToNothing' ma = case ma of
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Just' x | x > 0 -> Just' (x - 1)
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_ -> Nothing'
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safeHead :: [a] -> Maybe a
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safeHead (x:_) = Just x
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safeHead _ = Nothing
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safeUncons :: [a] -> Maybe (a,[a])
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safeUncons (x:xs) = Just (x,xs)
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safeUncons _ = Nothing
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errorHead :: String -> [a] -> a
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errorHead _ (x:_) = x
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errorHead s [] = error s
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aCrPos :: Int -> World -> Point2
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aCrPos i w = _crPos $ _creatures w IM.! i
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selectedObject :: World -> Maybe (Either FloorItem Button)
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selectedObject w = lookup (_crInvSel ycr) $ zip [n..] $ _closeObjects w
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where
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ycr = you w
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n = length $ _crInv ycr
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crItem :: World -> Int -> Item
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crItem w cid = _crInv cr IM.! _crInvSel cr
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where
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cr = _creatures w IM.! cid
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yourItemRef
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:: Applicative f
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=> World
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-> (Item -> f Item)
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-> World
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-> f World
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yourItemRef w = creatures . ix (_yourID w) . crInv . ix (_crInvSel (you w))
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wallNormal :: Wall -> Point2
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wallNormal = normalizeV . vNormal . uncurry (-.-) . _wlLine
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wallsOnLine :: Point2 -> Point2 -> IM.IntMap Wall -> IM.IntMap Wall
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wallsOnLine p1 p2 = IM.filter
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(isJust . uncurry (intersectSegSeg p1 p2) . _wlLine)
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wallsOnLineHit :: Point2 -> Point2 -> IM.IntMap Wall -> IM.IntMap (Point2, Wall)
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wallsOnLineHit p1 p2 = IM.mapMaybe f
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where
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f wl = uncurry (intersectSegSeg p1 p2) (_wlLine wl) <&> (, wl)
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wallsOnLine3D :: Point3 -> Point3 -> IM.IntMap Wall -> [Wall]
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wallsOnLine3D = undefined
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-- where
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-- hitPoint w = uncurry (intersectSegSeg p1 p2) (_wlLine w)
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-- hitWalls = filter (isJust . hitPoint) (IM.elems ws)
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wallsOnCirc :: Point2 -> Float -> IM.IntMap Wall -> IM.IntMap Wall
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wallsOnCirc p r = IM.filter f
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where
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f wl = uncurry circOnSeg (_wlLine wl) p r
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allWalls :: World -> IM.IntMap Wall
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allWalls = IM.unions . concatMap IM.elems . IM.elems . _znObjects . _wallsZone
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creatureNearPoint :: Point2 -> World -> Maybe Creature
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creatureNearPoint = creatureNearPointI 1
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creatureNearPointI :: Int -> Point2 -> World -> Maybe Creature
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creatureNearPointI n p = L.fold (L.minimumOn (dist p . _crPos)) . creaturesNearPointI n p
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creaturesNearPoint :: Point2 -> World -> IM.IntMap Creature
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creaturesNearPoint = creaturesNearPointI 1
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creaturesNearPointI :: Int -> Point2 -> World -> IM.IntMap Creature
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creaturesNearPointI n p w = IM.unions
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[f b $ f a $ _znObjects $ _creaturesZone w | a<-[x-n..x+n] , b<-[y-n..y+n]]
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where
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(x,y) = crZoneOfPoint p
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f i m = fromMaybe IM.empty $ IM.lookup i m
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-- possible BUG, occurs when used in thingsHitLongLine
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creaturesAlongLine :: Point2 -> Point2 -> World -> IM.IntMap Creature
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--creaturesAlongLine a b w = IM.unions [f y $ f x $ _creaturesZone w | (x,y) <- zoneOfLine a b]
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-- where f i m = case IM.lookup i m of Just val -> val
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-- _ -> IM.empty
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creaturesAlongLine a b w = IM.foldrWithKey' g IM.empty (zoneOfLineIntMap a b)
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where
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g x s = IM.union (IM.unions (IM.restrictKeys (f x $ _znObjects $ _creaturesZone w) s))
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f i = fromMaybe IM.empty . IM.lookup i
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-- f i m = case IM.lookup i m of Just val -> val
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-- _ -> IM.empty
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{- | Expands a line out to a given thickness. -}
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lineGeom :: Float -> Point2 -> Point2 -> [Point2]
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lineGeom t x y
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| x == y = []
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| otherwise = [x +.+ n x y, x -.- n x y, y +.+ n x y, y -.- n x y]
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where
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n a b = (t*0.5) *.* errorNormalizeV 4200 (vNormal (a -.- b))
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{- | A triangular wedge thick at the first point and
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- tapering off to the second. -}
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wedgeGeom
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:: Float -- Thickness
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-> Point2
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-> Point2
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-> [Point2]
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wedgeGeom t x y
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| x == y = []
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| otherwise = [x +.+ n x y, x -.- n x y, y]
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where
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n a b = (t*0.5) *.* errorNormalizeV 4200 (vNormal (a -.- b))
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insertInZoneWith
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:: Int -- ^ First Key
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-> Int -- ^ Second Key
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-> (a -> a -> a) -- ^ Combining function
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-> a -- ^ Value to insert
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-> IM.IntMap (IM.IntMap a)
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-> IM.IntMap (IM.IntMap a)
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insertInZoneWith x y fun obj = IM.insertWith f x $ IM.singleton y obj
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where
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f _ = IM.insertWith fun y obj
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{- | I believe this overwrites the value if it already exists, but not sure. -}
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insertIMInZone
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:: Int -- ^ First key
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-> Int -- ^ Second key
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-> Int -- ^ Third key
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-> a -- ^ Item to insert
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-> IM.IntMap (IM.IntMap (IM.IntMap a))
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-> IM.IntMap (IM.IntMap (IM.IntMap a))
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insertIMInZone x y obid obj = IM.insertWith f x $ IM.singleton y $ IM.singleton obid obj
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where
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f _ = IM.insertWith g y $ IM.singleton obid obj
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g _ = IM.insert obid obj
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deleteIMInZone
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:: Int -- ^ First key
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-> Int -- ^ Second key
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-> Int -- ^ Third key
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-> IM.IntMap (IM.IntMap (IM.IntMap a))
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-> IM.IntMap (IM.IntMap (IM.IntMap a))
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deleteIMInZone x y z = ix x . ix y %~ IM.delete z
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adjustIMZone
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:: (a -> a) -- ^ Update function
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-> Int -- ^ First key
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-> Int -- ^ Second key
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-> Int -- ^ Third key
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-> IM.IntMap (IM.IntMap (IM.IntMap a))
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-> IM.IntMap (IM.IntMap (IM.IntMap a))
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adjustIMZone f x y n = IM.adjust f' x
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where
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f' = IM.adjust f'' y
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f'' = IM.adjust f n
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{- | Finds unused projectile key. -}
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newProjectileKey :: World -> Int
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newProjectileKey = IM.newKey . _props
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{- | Finds unused creature key. -}
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newCrKey :: World -> Int
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newCrKey = IM.newKey . _creatures
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-- | Looks for overlap of a circle with walls.
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-- If found, gives wall
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overlapCircWallsReturnWall :: Point2 -> Float -> IM.IntMap Wall -> Maybe Wall
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overlapCircWallsReturnWall p rad
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= L.fold (safeMinimumOnMaybeL (fmap (dist p) . f . _wlLine))
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where
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f (a,b) = intersectSegSeg p (p -.- rad *.* vNormal (normalizeV (a -.- b))) a b
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-- | Looks for any collision of a circle with walls.
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-- If found, gives point and reflection velocity, reflection damped in normal.
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-- note that in this version the circle can overlap the wall
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collidePointAnyWallsReflect :: Point2 -> Point2 -> IM.IntMap Wall -> Maybe (Point2,Point2)
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collidePointAnyWallsReflect p1 p2
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= getFirst
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. foldMap (First . findPoint . _wlLine)
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where
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findPoint (x,y) = case intersectSegSeg p1 p2 x y of
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Just ip -> Just (ip +.+ normalizeV (vNormal (x -.- y)), reflectInParam 0.5 (x -.- y) (p2 -.- p1))
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Nothing -> Nothing
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-- | Looks for collision of a point with walls.
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-- If found, gives collision point
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-- If not found, returns point
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collidePointWalls :: Point2 -> Point2 -> IM.IntMap Wall -> Point2
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collidePointWalls p1 p2
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= foldr findPoint p2 . fmap _wlLine
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where
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findPoint (x,y) p = fromMaybe p $ intersectSegSeg p1 p x y
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collidePointWallsFilter :: (Wall -> Bool) -> Point2 -> Point2 -> IM.IntMap Wall -> Point2
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collidePointWallsFilter t p1 p2 = foldr findPoint p2 . fmap _wlLine . IM.filter t
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where
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findPoint (x,y) p = fromMaybe p $ intersectSegSeg p1 p x y
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collidePointWallsFilter' :: (Wall -> Bool) -> Point2 -> Point2 -> IM.IntMap Wall -> Point2
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collidePointWallsFilter' t p1 p2 = foldl' findPoint p2 . fmap _wlLine . IM.filter t
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where
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findPoint p = fromMaybe p . uncurry (intersectSegSeg p1 p)
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-- | Looks for first collision of a circle with walls.
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-- If found, gives point and reflection velocity, reflection damped in normal.
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-- note that the "intersection" point is the center of the circle flush against the wall
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collideCircWalls' :: Point2 -> Point2 -> Float -> IM.IntMap Wall -> Maybe (Point2,Point2)
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collideCircWalls' p1 p2 rad = either (const Nothing) Just . foldr findPoint (Left p2)
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where
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findPoint wl eip = maybe eip Right $ doReflection (getp eip) $ shiftByRad $ _wlLine wl
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getp (Left p) = p
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getp (Right (p,_)) = p
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doReflection p (x,y) = case intersectSegSeg p1 p x y of
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Nothing -> Nothing
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Just ip -> Just (ip +.+ normalizeV (vNormal (x -.- y)), reflectInParam 0.5 (x -.- y) (p2 -.- p1))
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shiftByRad (a,b) =
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(g $ a +.+ rad *.* normalizeV (a -.-b)
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,g $ b +.+ rad *.* normalizeV (b -.-a)
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)
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where
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g = ((rad *.* normalizeV (vNormal $ a -.- b)) +.+)
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-- | Looks for first collision of a circle with walls.
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-- If found, gives point and reflection velocity, reflection damped in normal.
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collideCircWalls :: Point2 -> Point2 -> Float -> IM.IntMap Wall -> Maybe (Point2,Point2)
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collideCircWalls p1 p2 rad
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= safeMinimumOn (dist p1 . fst)
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. IM.mapMaybe
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(( \(x:y:_) -> fmap
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((, reflectInParam 0.5 (x -.- y) (p2 -.- p1))
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. (+.+ normalizeV (vNormal (x -.- y)))
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)
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(intersectSegSeg p1 p2 x y)
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)
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. shiftByRad . _wlLine
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)
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where
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shiftByRad (a,b) = map ((rad *.* normalizeV (vNormal $ a -.- b)) +.+)
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[a +.+ rad *.* normalizeV (a -.-b)
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,b +.+ rad *.* normalizeV (b -.-a)
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]
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-- this shifts the wall out, and for outer corners extends the wall
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-- not sure what this does for inner corners, hopefully won't cause a problem
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-- the alternative would be to separately bounce off corner points...
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-- unfortunately, doesn't allow for collisions when the circle spawns on the
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-- wall
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-- | Looks for first collision of a point with a list of lines.
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-- If found, gives point and normal of wall.
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--collidePointLines :: Point2 -> Point2 -> [Wall'] -> Maybe (Point2,Point2)
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--collidePointLines p1 p2 ws
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-- = safeMinimumOn f
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-- $ mapMaybe (( \(x,y) -> intersectSegSeg p1 p2 x y <&> ( , vNormal $ x -.- y ) )
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-- . _wlLine') ws
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-- where
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-- f (a,_) = magV (p1 -.- a)
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--
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-- | Looks for first collision of a point with walls.
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-- If found, gives point and normal of wall.
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collidePointWallsNorm :: Point2 -> Point2 -> IM.IntMap Wall -> Maybe (Point2,Point2)
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collidePointWallsNorm p1 p2 ws
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= safeMinimumOn (dist p1 . fst)
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$ IM.mapMaybe (( \(x,y) -> intersectSegSeg p1 p2 x y <&> ( , vNormal $ x -.- y ) )
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. _wlLine) ws
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-- | Returns the first creature, if any, that a point intersects with.
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collidePointCreatures :: Point2 -> Point2 -> IM.IntMap Creature -> Maybe Int
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collidePointCreatures p1 p2 = fmap fst
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. safeMinimumOn snd
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. IM.toList
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. IM.mapMaybe (\x -> dist p1 <$> intersectCircSegFirst (_crPos x) (_crRad x) p1 p2)
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-- | As for 'collidePointCreatures', only increases the radius of creatures by a
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--fixed amount, thus collides a moving circle with creaures.
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collideCircCreatures :: Point2 -> Point2 -> Float -> IM.IntMap Creature -> Maybe Int
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collideCircCreatures p1 p2 rad = collidePointCreatures p1 p2 . fmap (crRad +~ rad)
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-- | Returns the first creature id, if any, that a point intersects with, gives point
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--in creature on line.
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collidePointCrsPoint :: Point2 -> Point2 -> IM.IntMap Creature -> Maybe (Point2,Int)
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collidePointCrsPoint p1 p2 = fmap f
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. safeMinimumOn (dist p1 . snd)
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. IM.toList
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. IM.mapMaybe (\x -> intersectCircSegFirst (_crPos x) (_crRad x) p1 p2)
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where
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f (cID,p) = (p,cID)
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{- | Finds the first creature hit on a line.
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Maybe evaluates the creature id and hit point. -}
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collideCircCrsPoint :: Point2 -> Point2 -> Float -> IM.IntMap Creature -> Maybe (Point2,Int)
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collideCircCrsPoint p1 p2 rad = collidePointCrsPoint p1 p2 . fmap (crRad +~ rad)
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---- | Makes a creature not hittable.
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--collidePointCrsWithoutPoint :: Int -> Point2 -> Point2 -> World -> Maybe (Point2,Int)
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--collidePointCrsWithoutPoint cid p1 p2 w
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-- = fmap f
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-- . safeMinimumOn (snd . snd)
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-- . IM.toList
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-- . IM.mapMaybe (\x -> collidePointCirc'' p1 p2 (_crRad x) (_crPos x))
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-- . IM.delete cid
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-- $ _creatures w
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-- where
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-- f (cID,(p,_)) = (p,cID)
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{- | Test if a circle collides with any wall.
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- Note no check on whether the wall is walkable. -}
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circOnSomeWall :: Point2 -> Float -> World -> Bool
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circOnSomeWall p rad
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= any (\(x,y) -> circOnSeg x y p rad)
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. fmap _wlLine
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. IM.elems
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. wallsNearPoint p
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{- | Test whether there is a creature of weight 4 or greater near a line. -}
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isHeavyCrNearLine
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:: Float
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-> [Point2]
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-> World
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-> Bool
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isHeavyCrNearLine d (p1:p2:_)
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= any (\c -> circOnSeg p1 p2 (_crPos c) (d + _crRad c))
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. IM.filter (\cr -> _crMass cr > 4)
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. _creatures
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isHeavyCrNearLine _ _ = error "Testing whether creature is near empty line"
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{- | Adds the distance to the creature radius, tests whether the center is in
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the circle of this size centered at the point -}
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crsNearPoint :: Float -> Point2 -> World -> Bool
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crsNearPoint d p = any (\c -> dist (_crPos c) p < (d + _crRad c)) . _creatures
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{- | Produce an unordered list of creatures on a line. -}
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crsOnLine :: Point2 -> Point2 -> World -> IM.IntMap Creature
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crsOnLine p1 p2
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= IM.filter (\cr -> circOnSeg p1 p2 (_crPos cr) (_crRad cr))
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. _creatures
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{- | Produce an unordered list of creatures on a wide line. -}
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crsOnThickLine :: Float -> Point2 -> Point2 -> World -> IM.IntMap Creature
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crsOnThickLine thickness p1 p2
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= IM.filter (\cr -> circOnSeg p1 p2 (_crPos cr) (_crRad cr + thickness))
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. _creatures
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{- | Find 'Maybe' the closest creature to a point, within a circle.
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-}
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nearestCrInRad :: Point2 -> Float -> World -> Maybe Creature
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nearestCrInRad p r
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= safeMinimumOn (dist p . _crPos)
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. IM.filter (\cr -> dist p (_crPos cr) < r)
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. _creatures
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{- | Find 'Maybe' the closest creature in front of a point in a right-angle-triangle shape. -}
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nearestCrInTri
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:: Point2
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-> Float -- ^ Direction (radians +ve anticlockwise from x-axis).
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-> Float -- ^ Distance.
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-> World -> Maybe Creature
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nearestCrInTri p dir x
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= safeMinimumOn (dist p . _crPos)
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. IM.filter (\cr -> pointInPolygon (_crPos cr) tri)
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. _creatures
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where
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tri =
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[p
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,p +.+ rotateV (dir-pi/4) (V2 x 0)
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,p +.+ rotateV (dir+pi/4) (V2 x 0)
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]
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{- | Find 'Maybe' the closes creature in front of a point in a given direction for
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a given distance.
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The shapes within which creatures are searched are a triangle then rectangle. -}
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nearestCrInFront
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:: Point2
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-> Float -- ^ Direction (radians +ve anticlockwise from x-axis).
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-> Float -- ^ Distance.
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-> World -> Maybe Creature
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nearestCrInFront p dir x
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= safeMinimumOn (dist p . _crPos)
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. IM.filter (\cr -> pointInPolygon (_crPos cr) rec)
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. _creatures
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where
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rec = [p, pR, pR1, pL1, pL ]
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pR = p +.+ rotateV (dir - pi*(3/8)) (V2 (x/2) 0)
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pL = p +.+ rotateV (dir + pi*(3/8)) (V2 (x/2) 0)
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pR1 = pR +.+ rotateV dir (V2 (x/2) 0)
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pL1 = pL +.+ rotateV dir (V2 (x/2) 0)
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{- | Test whether a creature is in a polygon. -}
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crInPolygon :: Creature -> [Point2] -> Bool
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crInPolygon = pointInPolygon . _crPos
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{- | Create a logistic function given three parameters. -}
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logistic :: Float -> Float -> Float -> (Float -> Float)
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logistic x0 l k x = l / (1 + exp (k*(x0 - x)))
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{- | given a target and a start point, shift toward the end point by a given
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amount.
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If close enough, end up on the end point -}
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mvPointTowardAtSpeed
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:: Float -- ^ Speed.
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-> Point2 -- ^ End point.
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-> Point2 -- ^ Start point.
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|
-> Point2
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|
mvPointTowardAtSpeed !speed !ep !p
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|
| dist p ep < speed = ep
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|
| otherwise = p +.+ speed *.* normalizeV (ep -.- p)
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|
{- | given a target and a start point, shift toward the end point by 1.
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|
If close enough, end up on the end point -}
|
|
mvPointToward
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|
:: Point2 -- ^ End point.
|
|
-> Point2 -- ^ Start point.
|
|
-> Point2
|
|
mvPointToward !ep !p
|
|
| dist p ep < 1 = ep
|
|
| otherwise = p +.+ normalizeV (ep -.- p)
|
|
|
|
isAnimate :: Creature -> Bool
|
|
{-# INLINE isAnimate #-}
|
|
isAnimate cr = case _crActionPlan cr of
|
|
Inanimate -> False
|
|
_ -> True
|
|
|
|
sigmoid :: Floating a => a -> a
|
|
sigmoid x = x/sqrt(1+x^(2::Int))
|
|
|
|
normalizeAnglePi :: Float -> Float
|
|
normalizeAnglePi angle
|
|
| normalizeAngle angle > pi = normalizeAngle angle - 2*pi
|
|
| otherwise = normalizeAngle angle
|
|
|
|
-- | Taken from online, splits a list into its even and odd elements
|
|
evenOddSplit :: [a] -> ([a],[a])
|
|
evenOddSplit = foldr f ([],[])
|
|
where
|
|
f a (ls,rs) = (rs, a : ls)
|
|
|
|
dbArg :: (a -> a -> b) -> a -> b
|
|
{-# INLINE dbArg #-}
|
|
dbArg f x = f x x
|
|
|
|
-- TODO check whether this is simply the reader monad, flipped
|
|
dbArgChain :: (a -> b -> b) -> (a -> b -> b) -> a -> b -> b
|
|
dbArgChain f g x = f x . g x
|