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Diffstat (limited to 'users/glittershark/xanthous/src/Xanthous/Generators/CaveAutomata.hs')
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1 files changed, 110 insertions, 0 deletions
diff --git a/users/glittershark/xanthous/src/Xanthous/Generators/CaveAutomata.hs b/users/glittershark/xanthous/src/Xanthous/Generators/CaveAutomata.hs new file mode 100644 index 000000000000..83740fe4b73d --- /dev/null +++ b/users/glittershark/xanthous/src/Xanthous/Generators/CaveAutomata.hs @@ -0,0 +1,110 @@ +{-# LANGUAGE MultiWayIf #-} +{-# LANGUAGE RecordWildCards #-} +{-# LANGUAGE TemplateHaskell #-} +-------------------------------------------------------------------------------- +module Xanthous.Generators.CaveAutomata + ( Params(..) + , defaultParams + , parseParams + , generate + ) where +-------------------------------------------------------------------------------- +import Xanthous.Prelude +import Control.Monad.Random (RandomGen, runRandT) +import Data.Array.ST +import Data.Array.Unboxed +import qualified Options.Applicative as Opt +-------------------------------------------------------------------------------- +import Xanthous.Util (between) +import Xanthous.Util.Optparse +import Xanthous.Data (Dimensions, width, height) +import Xanthous.Generators.Util +-------------------------------------------------------------------------------- + +data Params = Params + { _aliveStartChance :: Double + , _birthLimit :: Word + , _deathLimit :: Word + , _steps :: Word + } + deriving stock (Show, Eq, Generic) +makeLenses ''Params + +defaultParams :: Params +defaultParams = Params + { _aliveStartChance = 0.6 + , _birthLimit = 3 + , _deathLimit = 4 + , _steps = 4 + } + +parseParams :: Opt.Parser Params +parseParams = Params + <$> Opt.option parseChance + ( Opt.long "alive-start-chance" + <> Opt.value (defaultParams ^. aliveStartChance) + <> Opt.showDefault + <> Opt.help ( "Chance for each cell to start alive at the beginning of " + <> "the cellular automata" + ) + <> Opt.metavar "CHANCE" + ) + <*> Opt.option parseNeighbors + ( Opt.long "birth-limit" + <> Opt.value (defaultParams ^. birthLimit) + <> Opt.showDefault + <> Opt.help "Minimum neighbor count required for birth of a cell" + <> Opt.metavar "NEIGHBORS" + ) + <*> Opt.option parseNeighbors + ( Opt.long "death-limit" + <> Opt.value (defaultParams ^. deathLimit) + <> Opt.showDefault + <> Opt.help "Maximum neighbor count required for death of a cell" + <> Opt.metavar "NEIGHBORS" + ) + <*> Opt.option Opt.auto + ( Opt.long "steps" + <> Opt.value (defaultParams ^. steps) + <> Opt.showDefault + <> Opt.help "Number of generations to run the automata for" + <> Opt.metavar "STEPS" + ) + where + parseChance = readWithGuard + (between 0 1) + $ \res -> "Chance must be in the range [0,1], got: " <> show res + + parseNeighbors = readWithGuard + (between 0 8) + $ \res -> "Neighbors must be in the range [0,8], got: " <> show res + +generate :: RandomGen g => Params -> Dimensions -> g -> Cells +generate params dims gen + = runSTUArray + $ fmap fst + $ flip runRandT gen + $ generate' params dims + +generate' :: RandomGen g => Params -> Dimensions -> CellM g s (MCells s) +generate' params dims = do + cells <- randInitialize dims $ params ^. aliveStartChance + let steps' = params ^. steps + when (steps' > 0) + $ for_ [0 .. pred steps'] . const $ stepAutomata cells dims params + -- Remove all but the largest contiguous region of unfilled space + (_: smallerRegions) <- lift $ regions @UArray . amap not <$> freeze cells + lift $ fillAllM (fold smallerRegions) cells + lift $ fillOuterEdgesM cells + pure cells + +stepAutomata :: forall s g. MCells s -> Dimensions -> Params -> CellM g s () +stepAutomata cells dims params = do + origCells <- lift $ cloneMArray @_ @(STUArray s) cells + for_ (range ((0, 0), (dims ^. width, dims ^. height))) $ \pos -> do + neighs <- lift $ numAliveNeighborsM origCells pos + origValue <- lift $ readArray origCells pos + lift . writeArray cells pos + $ if origValue + then neighs >= params ^. deathLimit + else neighs > params ^. birthLimit |