diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,8 @@ +# Changelog + +## [Unreleased] + +## [1.0.0] -- 2018-05-24 +### Added +- `stack` support +- complete rewrite for `SDL2` diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,675 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. 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If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. + diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/driver/Main.hs b/driver/Main.hs new file mode 100644 --- /dev/null +++ b/driver/Main.hs @@ -0,0 +1,220 @@ +module Main where + +import Control.Lens + +import Game.HSnake.AI +import Game.HSnake.Basic +import Game.HSnake.Game +import Game.HSnake.Graphics +import Game.HSnake.Player +import Game.HSnake.Snake + +import Control.Monad +import Control.Monad.State +import Control.Monad.Reader +import Data.List +import Foreign.C.Types (CInt(..)) +import qualified SDL +import qualified SDL.Font as SDLF + + +data MessageDir = MessageDir { + quitMessage :: Bool +} + +data AppConfig = AppConfig { + window :: SDL.Window, + renderer :: SDL.Renderer, + gameScreen :: SDL.Surface, + messageDir :: MessageDir +} + +type AppState = StateT GameState IO +type AppEnv = ReaderT AppConfig AppState + + +initEnv :: IO (AppConfig, GameState) +initEnv = do + let windowSize = SDL.V2 (fromIntegral screenWidth :: CInt) (fromIntegral screenHeight :: CInt) + let p = SDL.defaultWindow {SDL.windowInitialSize = windowSize} + window <- SDL.createWindow "Haskell Snake" p + SDL.showWindow window + let screenSize = SDL.V2 (fromIntegral gameScreenWidth :: CInt) (fromIntegral gameScreenHeight :: CInt) + gameScreen <- SDL.createRGBSurface screenSize SDL.RGB24 + -- Renderer renders to gameScreen, not to window + -- We have text additionally to render to other parts of the window + -- If we rendered directly to window and then rendered text, this + -- would result in flickering + renderer <- SDL.createSoftwareRenderer gameScreen + + let msgDir = MessageDir False + + applePos <- getRandomApple initialSnakePosition + tick <- SDL.ticks + + return (AppConfig window renderer gameScreen msgDir, + applePosition .~ applePos $ + lastTick .~ tick $ initialGameState) -- timerState + + +runLoop :: AppConfig -> GameState -> IO () +runLoop = evalStateT . runReaderT loop + + +handleInputHuman :: GameState -> (Maybe SDL.Event) -> ReaderT AppConfig AppState () +handleInputHuman gs (Just (SDL.Event _ (SDL.KeyboardEvent k))) = + handleInputKeyboard gs k +handleInputHuman _ _ = return () + +handleInputKeyboard :: MonadState GameState m => GameState -> SDL.KeyboardEventData -> m () +handleInputKeyboard gs (SDL.KeyboardEventData _ SDL.Pressed False keysym) = + case SDL.keysymKeycode keysym of + SDL.KeycodeDown -> do + put $ players .~ moveHuman South $ gs + SDL.KeycodeUp -> do + put $ players .~ moveHuman North $ gs + SDL.KeycodeLeft -> do + put $ players .~ moveHuman West $ gs + SDL.KeycodeRight -> do + put $ players .~ moveHuman East $ gs + _ -> return () + where + moveHuman dir = mapToIndices (\pl -> setNextPlayerDirection pl dir) (gs^.players) humanPlayerIndices + where + humanPlayerIndices = findIndices isHuman (gs^.players) +handleInputKeyboard _ _ = return () + + + +-- | poll for event until it is SDL_QUIT or NoEvent +whileEvents :: MonadIO m => (Maybe SDL.Event -> m ()) -> m Bool +whileEvents act = do + event <- liftIO SDL.pollEvent + case event of + Just (SDL.Event _ SDL.QuitEvent) -> return True + _ -> do + act event + return False + + +loop :: AppEnv () +loop = do + gameState <- get + quit <- whileEvents $ handleInputHuman gameState + computeAINextMoves + + gameState <- get + + let apple = gameState^.applePosition + let ps = gameState^.players + + if checkPlayersCollision ps + then error "Game over" + else return () + + tick <- liftIO SDL.ticks + + let tickDifference = fromIntegral tick - fromIntegral (gameState^.lastTick) + + if (tickDifference > speedFromLevel (fromIntegral $ gameState^.level)) + then + do + -- Move the snake first, only then check for apple eating. + -- Otherwise we would eat the apple, then immediately move + -- the snake, which is wrong. + updatePlayerDirections + movePlayers + gameState <- get + put $ lastTick .~ tick $ gameState + + drawGame + + let appleEatersInd = findIndices (playerEatsApple apple) ps + if (length appleEatersInd > 0) + then do + newApplePosition <- liftIO $ getRandomApple (totalPlayersPosition ps) + -- increase snake's length + increaseAppleEatersLength appleEatersInd + gameState <- get + put $ applePosition .~ newApplePosition $ gameState + + else return () + else return () + + if (shouldIncreaseLevel ps) + then do + newApplePosition <- liftIO $ getRandomApple (totalPlayersPosition ps) + -- start new level after apple is eaten + put $ applePosition .~ newApplePosition $ + level .~ (gameState^.level) + 1 $ initialGameState + else return () + + unless quit loop + + loop + + +computeAINextMoves :: ReaderT AppConfig AppState () +computeAINextMoves = do + gameState <- get + put $ players .~ movedAI gameState $ gameState + where + aiIndices gs = findIndices (not . isHuman) (gs^.players) + movedAI gs = mapToIndices (\pl -> setNextPlayerDirection pl (computeAIPlayerMove pl gs)) (gs^.players) (aiIndices gs) + + +updatePlayerDirections :: ReaderT AppConfig AppState () +updatePlayerDirections = do + gameState <- get + put $ players .~ map updatePlayerDirection (gameState^.players) $ gameState + + +movePlayers :: ReaderT AppConfig AppState () +movePlayers = do + gameState <- get + put $ players .~ map movePlayer (gameState^.players) $ gameState + + +increaseAppleEatersLength :: [Int] -> ReaderT AppConfig AppState () +increaseAppleEatersLength appleEatersIndices = do + gameState <- get + put $ players .~ mapToIndices increasePlayerSnakeLength (gameState^.players) appleEatersIndices $ gameState + + +drawGame :: ReaderT AppConfig AppState () +drawGame = do + window <- window `liftM` ask + renderer <- renderer `liftM` ask + gameScreen <- gameScreen `liftM` ask + gameState <- get + + liftIO $ do + -- clear window surface first + screen <- SDL.getWindowSurface window + clearSurface screen + + paintBoard renderer + paintApple renderer (gameState^.applePosition) + mapM_ (paintPlayer renderer) (gameState^.players) + + SDL.present renderer + + showGameMessages window gameState + + _ <- SDL.surfaceBlit gameScreen Nothing screen Nothing + + SDL.updateWindowSurface window + + SDL.freeSurface screen + + return () + + +main :: IO () +main = do + SDL.initializeAll + SDLF.initialize + + (env, snakeState) <- initEnv + + runLoop env snakeState diff --git a/driver/MainWrapper.hs b/driver/MainWrapper.hs new file mode 100644 --- /dev/null +++ b/driver/MainWrapper.hs @@ -0,0 +1,5 @@ +{-# LANGUAGE ForeignFunctionInterface #-} + +module MainWrapper where +import Main (main) +foreign export ccall "haskell_main" main :: IO () diff --git a/haskell-snake.cabal b/haskell-snake.cabal new file mode 100644 --- /dev/null +++ b/haskell-snake.cabal @@ -0,0 +1,76 @@ +-- This file has been generated from package.yaml by hpack version 0.27.0. +-- +-- see: https://github.com/sol/hpack +-- +-- hash: 60583e315dd2851d455eb1c3beba4cfd260b5fecb8b670efc23c1f0c6070679a + +name: haskell-snake +version: 1.0.0 +synopsis: Snake game implemetation in Haskell using SDL2 +description: See README at +category: Games +homepage: https://github.com/CGenie/haskell-snake#readme +bug-reports: https://github.com/CGenie/haskell-snake/issues +maintainer: Przemysław Kamiński +license: GPL-3 +license-file: LICENSE +build-type: Simple +cabal-version: >= 1.10 + +extra-source-files: + CHANGELOG.md + +source-repository head + type: git + location: https://github.com/CGenie/haskell-snake + +library + exposed-modules: + Game.HSnake.AI + Game.HSnake.Basic + Game.HSnake.Board + Game.HSnake.Game + Game.HSnake.Graphics + Game.HSnake.Player + Game.HSnake.Snake + other-modules: + Paths_haskell_snake + hs-source-dirs: + src + default-extensions: EmptyCase FlexibleContexts FlexibleInstances InstanceSigs MultiParamTypeClasses LambdaCase MultiWayIf NamedFieldPuns TupleSections DeriveFoldable DeriveFunctor DeriveGeneric DeriveLift DeriveTraversable DerivingStrategies GeneralizedNewtypeDeriving StandaloneDeriving BangPatterns KindSignatures TypeOperators OverloadedStrings ScopedTypeVariables TypeApplications ConstraintKinds RankNTypes DefaultSignatures PatternSynonyms TemplateHaskell + ghc-options: -Wall -Wincomplete-patterns -Wincomplete-uni-patterns -Wredundant-constraints + build-depends: + base >=4.9 && <5 + , containers + , lens + , linear + , mtl + , random + , sdl2 + , sdl2-ttf + , text + , vector + default-language: Haskell2010 + +executable haskell-snake + main-is: Main.hs + other-modules: + MainWrapper + Paths_haskell_snake + hs-source-dirs: + driver + default-extensions: EmptyCase FlexibleContexts FlexibleInstances InstanceSigs MultiParamTypeClasses LambdaCase MultiWayIf NamedFieldPuns TupleSections DeriveFoldable DeriveFunctor DeriveGeneric DeriveLift DeriveTraversable DerivingStrategies GeneralizedNewtypeDeriving StandaloneDeriving BangPatterns KindSignatures TypeOperators OverloadedStrings ScopedTypeVariables TypeApplications ConstraintKinds RankNTypes DefaultSignatures PatternSynonyms TemplateHaskell + ghc-options: -Wall -Wincomplete-patterns -Wincomplete-uni-patterns -Wredundant-constraints + build-depends: + base >=4.9 && <5 + , containers + , haskell-snake + , lens + , linear + , mtl + , random + , sdl2 + , sdl2-ttf + , text + , vector + default-language: Haskell2010 diff --git a/src/Game/HSnake/AI.hs b/src/Game/HSnake/AI.hs new file mode 100644 --- /dev/null +++ b/src/Game/HSnake/AI.hs @@ -0,0 +1,33 @@ +module Game.HSnake.AI where + +import Control.Lens + +import Game.HSnake.Basic +import Game.HSnake.Game +import Game.HSnake.Player +import Game.HSnake.Snake + +computeAIPlayerMove :: Player -> GameState -> Direction +computeAIPlayerMove pl gameState = circleAIPlayer pl + + +circleAIPlayer :: Player -> Direction +circleAIPlayer pl + -- corner cases + | headPos^.x == 1 && dir == West && headPos^.y <= 2 = South + | headPos^.x == 1 && dir == West && headPos^.y > 2 = North + | headPos^.x == (numRectsX - 1) && dir == East && headPos^.y <= 2 = South + | headPos^.x == (numRectsX - 1) && dir == East && headPos^.y > 2 = North + | headPos^.y == 1 && dir == North && headPos^.x >= 2 = West + | headPos^.y == 1 && dir == North && headPos^.x < 2 = East + | headPos^.y == (numRectsY - 1) && dir == South && headPos^.x >= 2 = West + | headPos^.y == (numRectsY - 1) && dir == South && headPos^.x < 2 = East + -- normal operation + | headPos^.y <= 2 = South + | headPos^.y >= (numRectsX - 2) = North + | headPos^.y <= 2 = West + | headPos^.y >= (numRectsY - 2) = East + | otherwise = pl^.snake^.direction + where + headPos = head $ pl^.snake^.position + dir = pl^.snake^.direction diff --git a/src/Game/HSnake/Basic.hs b/src/Game/HSnake/Basic.hs new file mode 100644 --- /dev/null +++ b/src/Game/HSnake/Basic.hs @@ -0,0 +1,71 @@ +-- Basic.hs -- basic functions and datatypes +module Game.HSnake.Basic where + +import Control.Lens + +import Data.List +import System.Random + +--data Colors = White | Black + +data Colour = White | Red | Blue | Green | Yellow | Black + deriving (Eq, Show) + +data Point = Point { + _x :: Int, + _y :: Int +} deriving (Show, Eq, Ord) + +makeLenses ''Point + +infixl 6 |+| +(|+|) :: Point -> Point -> Point +pt1 |+| pt2 = Point (pt1^.x + pt2^.x) (pt1^.y + pt2^.y) + +data Direction = North | South | East | West + deriving (Show, Eq, Ord) + +-- | board size +numRectsX :: Int +numRectsX = 11 +-- | board size +numRectsY :: Int +numRectsY = 11 + +oppositeDirections :: Direction -> Direction -> Bool +oppositeDirections dir1 dir2 + | ss == sort [North, South] = True + | ss == sort [East, West] = True + | otherwise = False + where + ss = sort [dir1, dir2] + +directionToPoint :: Direction -> Point +directionToPoint North = Point 0 (-1) +directionToPoint South = Point 0 1 +directionToPoint East = Point 1 0 +directionToPoint West = Point (-1) 0 + +randomListGenerator = do + seed <- newStdGen + return $ randomlist seed + where + randomlist = unfoldr (Just . random) + +getRandomApple snakePosition = do + r1 <- randomListGenerator + r2 <- randomListGenerator + let pts = map modPoint (zip r1 r2) + return $ head $ filter (\pt -> (not . elem pt) snakePosition) pts + where + modPoint (x, y) = Point ((x `mod` numRectsX) + 1) ((y `mod` numRectsY) + 1) + +-- | maps function to list, but only to specific indices +mapToIndices :: (Eq a) => (a -> a) -> [a] -> [Int] -> [a] +mapToIndices f xs ind = mapToIndices' f xs ind 0 + where + mapToIndices' f' (x':xs') (ind':inds') i + | ind' == i = (f' x':mapToIndices' f' xs' inds' (i + 1)) + | otherwise = (x':mapToIndices' f' xs' (ind':inds') (i + 1)) + mapToIndices' f' [] _ _ = [] + mapToIndices' f' xs' [] _ = xs' diff --git a/src/Game/HSnake/Board.hs b/src/Game/HSnake/Board.hs new file mode 100644 --- /dev/null +++ b/src/Game/HSnake/Board.hs @@ -0,0 +1,15 @@ +-- Board.hs -- board logic +module Game.HSnake.Board where + +import Control.Lens + +import Game.HSnake.Basic + +data Board = Board { + _xSize :: Int, + _ySize :: Int +} deriving (Eq, Show) + +makeLenses ''Board + +initialBoard = Board numRectsX numRectsY diff --git a/src/Game/HSnake/Game.hs b/src/Game/HSnake/Game.hs new file mode 100644 --- /dev/null +++ b/src/Game/HSnake/Game.hs @@ -0,0 +1,33 @@ +module Game.HSnake.Game where + +import Game.HSnake.Basic +import Game.HSnake.Board +import Game.HSnake.Player +import Game.HSnake.Snake + +import Control.Lens +import Data.Word + +data GameState = GameState { + _players :: [Player], + _applePosition :: Game.HSnake.Basic.Point, + _board :: Board, + _level :: Int, + _lastTick :: Word32 +} +makeLenses ''GameState + +initialGameState :: GameState +initialGameState = GameState + [initialPlayer, initialComputer] + (Game.HSnake.Basic.Point 0 0) + initialBoard + 1 + 0 + +speedFromLevel :: Integer -> Integer +speedFromLevel l = toInteger $ floor $ (380 * (0.5**(0.1 * (fromIntegral l))) + 20) + +-- if snake's length is greater than 10, then increase level +shouldIncreaseLevel :: [Player] -> Bool +shouldIncreaseLevel ps = length (filter (>=10) (map (\pl -> pl^.snake^.len) ps)) > 0 diff --git a/src/Game/HSnake/Graphics.hs b/src/Game/HSnake/Graphics.hs new file mode 100644 --- /dev/null +++ b/src/Game/HSnake/Graphics.hs @@ -0,0 +1,137 @@ +module Game.HSnake.Graphics where + +import Game.HSnake.Basic +import Game.HSnake.Board +import Game.HSnake.Game +import Game.HSnake.Player +import Game.HSnake.Snake + + +import Control.Lens +import Control.Monad.IO.Class (MonadIO(..)) +import Data.Text (pack) +import qualified Data.Vector.Storable as DVS +import Data.Word +import Linear +import Linear.Affine +import Foreign.C.Types (CInt(..)) +import qualified SDL +import qualified SDL.Font as SDLF + + +type SDLRect = SDL.Rectangle CInt + + +setColor :: SDL.Renderer -> Colour -> IO () +setColor r White = SDL.rendererDrawColor r SDL.$= SDL.V4 maxBound maxBound maxBound maxBound +setColor r Red = SDL.rendererDrawColor r SDL.$= SDL.V4 maxBound 0 0 maxBound +setColor r Green = SDL.rendererDrawColor r SDL.$= SDL.V4 0 maxBound 0 maxBound +setColor r Blue = SDL.rendererDrawColor r SDL.$= SDL.V4 0 0 maxBound maxBound +setColor r Yellow = SDL.rendererDrawColor r SDL.$= SDL.V4 maxBound maxBound 0 maxBound +setColor r Black = SDL.rendererDrawColor r SDL.$= SDL.V4 0 0 0 maxBound + +sdlColor :: Colour -> SDLF.Color +sdlColor Black = SDL.V4 0 0 0 maxBound +sdlColor White = SDL.V4 maxBound maxBound maxBound maxBound + +screenWidth :: Int +screenWidth = 640 +screenHeight :: Int +screenHeight = 480 +screenBpp :: Int +screenBpp = 32 + +gameScreenWidth :: Int +gameScreenWidth = 540 +gameScreenHeight :: Int +gameScreenHeight = 400 + +messageScreenWidth :: Int +messageScreenWidth = screenWidth - gameScreenWidth +messageScreenHeight :: Int +messageScreenHeight = screenHeight - gameScreenHeight + +rectWidth :: Int +rectWidth = gameScreenWidth `div` numRectsX +rectHeight :: Int +rectHeight = gameScreenHeight `div` numRectsY + + +rectFromPoint :: Game.HSnake.Basic.Point -> SDLRect +rectFromPoint (Game.HSnake.Basic.Point x y) = SDL.Rectangle startPoint size + where + startX = (x - 1)*rectWidth + 1 + startY = (y - 1)*rectHeight + 1 + width = rectWidth - 1 + height = rectHeight - 1 + startPoint = P $ V2 (fromIntegral startX) (fromIntegral startY) + size = V2 (fromIntegral width) (fromIntegral height) + + +rects = [rectFromPoint (Game.HSnake.Basic.Point ptx pty) | ptx <- [1..numRectsX], pty <- [1..numRectsY]] +rectsVec = DVS.generate (numRectsX * numRectsY) + (\i -> rects !! i ) + + +paintRects :: SDL.Renderer -> Colour -> IO () +paintRects r color = do + setColor r color + SDL.fillRects r rectsVec + +paintBoard :: SDL.Renderer -> IO () +paintBoard r = do + paintRects r White + +paintApple :: SDL.Renderer -> Game.HSnake.Basic.Point -> IO () +paintApple r ap = do + setColor r Red + SDL.fillRect r $ Just rect + where + rect = rectFromPoint ap + +-- | TODO: paint different snakes with different colors +paintPlayer :: SDL.Renderer -> Player -> IO () +paintPlayer r p = paintSnake r (p^.snake) (p^.colour) + + +paintSnake :: SDL.Renderer -> Snake -> Colour -> IO () +paintSnake r s c = + mapM_ (\p -> paintSnakePiece r (rectFromPoint p) c) (s^.position) + +paintSnakePiece :: SDL.Renderer -> SDLRect -> Colour -> IO () +paintSnakePiece r rect c = do + setColor r c + SDL.fillRect r $ Just rect + +showGameMessages :: SDL.Window -> GameState -> IO () +showGameMessages w gameState = do + font <- SDLF.load "liberation.ttf" 25 + + surface <- SDLF.solid font color levelMessage + + screen <- SDL.getWindowSurface w + + renderSurfaceToWindow w screen surface startPoint + + SDL.freeSurface screen + SDL.freeSurface surface + SDLF.free font + + where + levelMessage = pack $ "Level " ++ (show $ gameState^.level) + color = sdlColor White + startPoint = P $ V2 (fromIntegral gameScreenWidth) 0 + +renderSurfaceToWindow :: (MonadIO m) => SDL.Window -> SDL.Surface -> SDL.Surface -> (SDL.Point V2 CInt) -> m () +renderSurfaceToWindow w s i startPoint = do + SDL.surfaceBlit i Nothing s (Just startPoint) + return () + +clearScreen :: SDL.Renderer -> IO () +clearScreen r = do + setColor r Black + SDL.clear r + +clearSurface :: SDL.Surface -> IO () +clearSurface s = do + SDL.surfaceFillRect s Nothing (sdlColor Black) diff --git a/src/Game/HSnake/Player.hs b/src/Game/HSnake/Player.hs new file mode 100644 --- /dev/null +++ b/src/Game/HSnake/Player.hs @@ -0,0 +1,78 @@ +module Game.HSnake.Player where + +import Control.Lens + +import Game.HSnake.Basic +import Game.HSnake.Snake + +import Data.List + +data PlayerType = AI | Human + deriving (Eq, Show) + +data Player = Player { + _playerType :: PlayerType + ,_snake :: Snake + {-| + Temporary state variable to store next move's snake direction + Without this when snake went North, and user quickly typed + West, then South, snake would bump into itself + -} + ,_nextSnakeDirection :: Direction + ,_colour :: Colour +} deriving (Eq, Show) + +makeLenses ''Player + +initialPlayer :: Player +initialPlayer = Player + Human + initialSnake + (initialSnake^.direction) + Green + +initialPlayerBottom :: Player +initialPlayerBottom = Player + Human + initialSnakeBottom + (initialSnakeBottom^.direction) + Green + +initialComputer :: Player +initialComputer = Player + AI + initialSnakeBottom + (initialSnakeBottom^.direction) + Blue + +isHuman :: Player -> Bool +isHuman (Player Human _ _ _) = True +isHuman _ = False + +checkPlayerCollision :: Player -> Bool +checkPlayerCollision player = checkCollision $ player^.snake + +movePlayer :: Player -> Player +movePlayer pl = snake .~ (moveSnake $ pl^.snake) $ pl + +playerEatsApple :: Point -> Player -> Bool +playerEatsApple apple player = snakeEatsApple (player^.snake) apple + +sumPlayersPosition :: [Player] -> [Point] +sumPlayersPosition ps = foldl (++) [] $ map (\pl -> pl^.snake^.position) ps + +totalPlayersPosition :: [Player] -> [Point] +totalPlayersPosition = nub . sumPlayersPosition + +checkPlayersCollision :: [Player] -> Bool +checkPlayersCollision ps = (length (filter checkPlayerCollision ps) > 0) || + (length (totalPlayersPosition ps) < (length (sumPlayersPosition ps))) + +increasePlayerSnakeLength :: Player -> Player +increasePlayerSnakeLength pl = snake .~ (increaseSnakeLength $ pl^.snake) $ pl + +setNextPlayerDirection :: Player -> Direction -> Player +setNextPlayerDirection pl dir = nextSnakeDirection .~ dir $ pl + +updatePlayerDirection :: Player -> Player +updatePlayerDirection pl = snake .~ changeSnakeDirection (pl^.snake) (pl^.nextSnakeDirection) $ pl diff --git a/src/Game/HSnake/Snake.hs b/src/Game/HSnake/Snake.hs new file mode 100644 --- /dev/null +++ b/src/Game/HSnake/Snake.hs @@ -0,0 +1,71 @@ +-- Snake.hs: Snake-control logic +module Game.HSnake.Snake where + +import Control.Lens + +import Game.HSnake.Basic + +import Data.List (nub, sort) + +data Snake = Snake { + -- | Snake's position is a list containing all its elements. + -- The first element of this list is snake's head. + _position :: [Point], + _direction :: Direction, + -- | Snake's length + -- We need to keep it -- if we initialize new level with large + -- snake length, we initially get a shorter snake so + -- snake^.position is not the correct snake's measure + _len :: Int +} deriving (Show, Eq) + +makeLenses ''Snake + +-- | Increases snake's length by 1 +increaseSnakeLength :: Snake -> Snake +increaseSnakeLength = len +~ 1 + +-- | Moves snake according to it's direction +moveSnake :: Snake -> Snake +moveSnake snake = position .~ newPosition $ snake + where + -- |check snake's length, if newPosition contains too many elements, remove them + newPosition = take (snake^.len) + ((head (snake^.position) |+| directionToPoint (snake^.direction)) : + (snake^.position)) + +-- | Basically we check if there are 2 same elements in the 'position' list +checkCollision :: Snake -> Bool +checkCollision snake = outOfBoundary || selfCollision + where + snakePosition = snake^.position + mini = head $ sort snakePosition + maxi = head $ reverse $ sort snakePosition + outOfBoundary = (mini^.x < 1) || (mini^.y < 1) || + (maxi^.x > numRectsX) || (maxi^.y > numRectsY) + selfCollision = (length (nub snakePosition)) /= (length snakePosition) + +-- | Starting position & body +initialSnakePosition :: [Point] +initialSnakePosition = [Point 6 6] + +initialSnakePositionBottom :: [Point] +initialSnakePositionBottom = [Point 6 11] + +initialSnake :: Snake +initialSnake = Snake initialSnakePosition North 1 + +initialSnakeBottom :: Snake +initialSnakeBottom = Snake initialSnakePositionBottom North 1 + +snakeEatsApple :: Snake -> Point -> Bool +snakeEatsApple snake apple = apple `elem` (snake^.position) + +-- | Don't allow to change to opposite direction immediately +tryChangeSnakeDirection :: Direction -> Direction -> Direction +tryChangeSnakeDirection d sd + | oppositeDirections d sd = sd + | otherwise = d + +changeSnakeDirection :: Snake -> Direction -> Snake +changeSnakeDirection s d = direction .~ (tryChangeSnakeDirection d (s^.direction)) $ s