raycharles/src/Main.hs

154 lines
3.7 KiB
Haskell

module Main where
import Linear
import Data.Matrix as M
import Data.List as L
import Data.Maybe
import Control.Monad
import Control.Monad.Loops
import Control.Concurrent
import Control.Concurrent.Timer
import Control.Concurrent.Suspend.Lifted
import Control.Concurrent.MVar
import Control.DeepSeq
import System.IO
import System.Console.ANSI as CA
import System.Console.Terminal.Size as TS
-- import Debug.Trace as T
import qualified Map
import Types
delay :: Delay
delay = msDelay (fromIntegral msdelay)
msdelay :: Int
msdelay = 100
step :: V2 Double
step = V2 0 0.5
rotStep :: Double
rotStep = 0.174533
fov :: Double
fov = pi / 2
main :: IO ()
main = do
hSetBuffering stdin NoBuffering
hideCursor
state <- newMVar (State (V2 10 3) 0 False "")
c <- newMVar Nothing
whileM_ (not <$> stop <$> readMVar state) $ do
CA.clearScreen
takeMVar c
char <- getKey
putMVar c char
modifyMVar_ state (\s -> if (not (stop s))
then
withMVar c (\char -> handleInput char s)
else
return s)
outputs <- withMVar state draw
withMVar state (\s -> when (not (stop s)) $ do
let output = L.intercalate "\n"
( outputs
++ [show char]
++ [show (pos s) ++ " " ++ show (rot s)]
)
deepseq output (putStr output)
)
-- threadDelay msdelay
showCursor
handleInput :: Maybe Char -> State -> IO State
handleInput Nothing state = return state
handleInput (Just char) state = do
let npos delta = if not (doesCollide (pos state + delta))
then pos state + delta
else pos state
nstate = case char of
'w' -> state
{ pos = npos (step `rotVec` rot state) }
's' -> state
{ pos = npos (- step `rotVec` rot state) }
'd' -> state
{ rot = rot state + rotStep }
'a' -> state
{ rot = rot state - rotStep }
'\ESC' -> state
{ stop = True }
_ -> state
return nstate
draw :: State -> IO [String]
draw state@(State pos@(V2 x y) rot _ _) = do
(Just (Window h w)) <- TS.size
let dims@(dw, dh) = (min 160 w, min 60 h) -- if w >= h then (w, w `div` 2) else (w, h)
output = map
(\mh -> map (\mw -> drawPixel dims (mw, mh)) [1 .. fromIntegral dw])
[1 .. fromIntegral dh - 2]
return output
where
drawPixel (w, h) (ddw, ddh) =
let rayLength = castRay (fromIntegral w) (fromIntegral h) ddw ddh
in getPixel (fromMaybe 11 rayLength)
castRay w h ddw ddh =
let iter = [0, 0.05 .. 10]
collPos a = (pos + (V2 0 (a * cos (- fov / 2 + ddh * fov / h))
`rotVec` (rot - fov / 2 + ddw * fov / w)))
in foldl (\acc a ->
if isNothing acc
then
if doesCollide (collPos a)
then Just a
else acc
else acc
) Nothing iter
getPixel l
| l <= 3 = '█'
| l <= 4.5 = '▓'
| l <= 6 = '▒'
| l <= 9 = '░'
| otherwise = ' '
doesCollide :: V2 Double -> Bool
doesCollide (V2 x y) =
let tile = safeGet (floor x) (floor y) Map.map
in case tile of
Nothing -> True
Just '#' -> True
_ -> False
rotVec (V2 x y) rad = V2 nx ny
where
nx = x * cos rad + y * sin rad
ny = x * sin rad - y * cos rad
getKey :: IO (Maybe Char)
getKey = do
charMVar <- newEmptyMVar
tid <- forkIO (forkGetChar charMVar)
threadDelay (msdelay `div` 5)
empty <- isEmptyMVar charMVar
if (not empty)
then do
killThread tid
Just <$> takeMVar charMVar
else do
killThread tid
return Nothing
where
forkGetChar mvar = do
hSetEcho stdin False
cs <- (: []) <$> hGetChar stdin
hSetEcho stdin True
when (not (null cs)) $ do
_ <- putMVar mvar (head cs)
return ()