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|
{-# LANGUAGE PatternGuards, GeneralizedNewtypeDeriving #-}
import Game
import Level
import Render
import Tank
import GLDriver
import GLX
import Control.Concurrent (threadDelay)
import Control.Monad.State
import Data.Maybe
import qualified Data.Map as M
import Data.Ratio
import qualified Data.Set as S
import Data.Time.Clock
data MainState = MainState
{ run :: !Bool
, driver :: !SomeDriver
, time :: !UTCTime
, keyset :: !(S.Set Key)
}
newtype MainT m a = MainT (StateT MainState m a)
deriving (Monad, MonadState MainState, MonadIO, MonadTrans)
type Main = MainT Game
runMain :: MainState -> Main a -> Game (a, MainState)
runMain st (MainT a) = runStateT a st
main :: IO ()
main = do
gl <- initGL glxDriver
when (initialized gl) $ do
currentTime <- getCurrentTime
let mainState = MainState {run = True, driver = SomeDriver gl, time = currentTime, keyset = S.empty}
gameState = GameState {level = testLevel, tanks = [Tank 0.0 0.0 0 0 2], textures = M.empty}
runGame gameState $ do
setup 800 600
runMain mainState mainLoop
deinitGL gl
minFrameTime :: NominalDiffTime
minFrameTime = 0.01
mainLoop :: Main ()
mainLoop = do
gl <- gets driver
t <- gets time
handleEvents
lift render
liftIO $ swapBuffers gl
rtime <- liftIO getCurrentTime
let drender = diffUTCTime rtime t
when (drender < minFrameTime) $
liftIO $ threadDelay $ truncate $ 1e6*(minFrameTime - drender)
currenttime <- liftIO getCurrentTime
let d = round $ 1e3*(diffUTCTime currenttime t)
replicateM_ d simulationStep
--liftIO $ print $ d
let newtime = addUTCTime ((1e-3)*(fromIntegral d)) t
modify $ \state -> state {time = newtime}
runnext <- gets run
when runnext mainLoop
simulationStep :: Main ()
simulationStep = do
keys <- gets keyset
let x = (if (S.member KeyLeft keys) then (-1) else 0) + (if (S.member KeyRight keys) then 1 else 0)
y = (if (S.member KeyDown keys) then (-1) else 0) + (if (S.member KeyUp keys) then 1 else 0)
let lengthsq = ((x*x)+(y*y))
when (lengthsq /= 0) $ do
let length = sqrt lengthsq
oldtank <- lift $ gets (head . tanks)
let dx = (speed oldtank) * fromRational (round (x*1000/length)%1000000)
dy = (speed oldtank) * fromRational (round (y*1000/length)%1000000)
let tank = oldtank {posx = dx + posx oldtank, posy = dy + posy oldtank, dir = fromRational $ round ((atan2 y x)*1000000*180/pi)%1000000}
lift $ modify $ \state -> state {tanks = tank:(tail . tanks $ state)}
handleEvents :: Main ()
handleEvents = do
event <- gets driver >>= liftIO . nextEvent
when (isJust event) $
handleEvent $ fromJust event
handleEvent :: SomeEvent -> Main ()
handleEvent ev
| Just (ResizeEvent w h) <- fromEvent ev = lift $ resize w h
| Just (KeyPressEvent key) <- fromEvent ev = modify $ \state -> state {keyset = S.insert key (keyset state)}
| Just (KeyReleaseEvent key) <- fromEvent ev = modify $ \state -> state {keyset = S.delete key (keyset state)}
| Just QuitEvent <- fromEvent ev = modify $ \state -> state {run = False}
| otherwise = return ()
|
