Main.hs

   1 module Main where
   2
   3 import Data.Function (fix)
   4 import Data.IORef (newIORef, readIORef, writeIORef)
   5 import Control.Monad
   6 import Control.Monad.State
   7
   8
   9 import Clock
  10 import Video
  11 import Audio
  12 import World
  13 import Input
  14 import Output
  15
  16
  17 main :: IO ()
  18 main = do
  19   video <- startVideo 320 240 UseSDL
  20   audio <- startAudio
  21   world <- (loadWorld video) >>= newIORef
  22   quitRef <- newIORef False
  23   clock <- mkClock 10  -- use 10ms time quantum (max 100fps)
  24   fix $ \loop -> do
  25     n <- readNewClockTicks clock   -- blocks until n > 0
  26     replicateM_ n $ do
  27       inputs <- readRawInput quitRef
  28       w <- readIORef world
  29       let (w',outs) = runWorld inputs w -- 1 game step
  30       writeIORef world w'
  31       forM_ outs (execOutput video audio)
  32     readIORef world >>= renderWorld video -- one graphics frame
  33     done <- readIORef quitRef
  34     when (not done) loop
  35   endAudio
  36   endVideo
  37
  38