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module Xanthous.Generators.LevelContents
( chooseCharacterPosition
, randomItems
, randomCreatures
, tutorialMessage
) where
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import Xanthous.Prelude
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import Control.Monad.Random
import Data.Array.IArray (amap, bounds, rangeSize, (!))
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import Xanthous.Generators.Util
import Xanthous.Random
import Xanthous.Data (Position, _Position, positionFromPair)
import Xanthous.Data.EntityMap (EntityMap, _EntityMap)
import Xanthous.Entities.Raws (rawsWithType, RawType)
import qualified Xanthous.Entities.Item as Item
import Xanthous.Entities.Item (Item)
import qualified Xanthous.Entities.Creature as Creature
import Xanthous.Entities.Creature (Creature)
import Xanthous.Entities.Environment (GroundMessage(..))
import Xanthous.Messages (message_)
import Xanthous.Util.Graphics (circle)
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chooseCharacterPosition :: MonadRandom m => Cells -> m Position
chooseCharacterPosition = randomPosition
randomItems :: MonadRandom m => Cells -> m (EntityMap Item)
randomItems = randomEntities Item.newWithType (0.0004, 0.001)
randomCreatures :: MonadRandom m => Cells -> m (EntityMap Creature)
randomCreatures = randomEntities Creature.newWithType (0.0007, 0.003)
tutorialMessage :: MonadRandom m
=> Cells
-> Position -- ^ CharacterPosition
-> m (EntityMap GroundMessage)
tutorialMessage cells characterPosition = do
let distance = 2
pos <- fmap (fromMaybe (error "No valid positions for tutorial message?"))
. choose . ChooseElement
$ accessiblePositionsWithin distance cells characterPosition
msg <- message_ ["tutorial", "message1"]
pure $ _EntityMap # [(pos, GroundMessage msg)]
where
accessiblePositionsWithin :: Int -> Cells -> Position -> [Position]
accessiblePositionsWithin dist valid pos =
review _Position
<$> filter (\(px, py) -> not $ valid ! (fromIntegral px, fromIntegral py))
(circle (pos ^. _Position) dist)
randomEntities
:: forall entity raw m. (MonadRandom m, RawType raw)
=> (raw -> entity)
-> (Float, Float)
-> Cells
-> m (EntityMap entity)
randomEntities newWithType sizeRange cells =
case fromNullable $ rawsWithType @raw of
Nothing -> pure mempty
Just raws -> do
let len = rangeSize $ bounds cells
(numEntities :: Int) <-
floor . (* fromIntegral len) <$> getRandomR sizeRange
entities <- for [0..numEntities] $ const $ do
pos <- randomPosition cells
raw <- choose raws
let entity = newWithType raw
pure (pos, entity)
pure $ _EntityMap # entities
randomPosition :: MonadRandom m => Cells -> m Position
randomPosition cells = fmap positionFromPair . choose $ impureNonNull candidates
where
-- cells ends up with true = wall, we want true = can put an item here
placeableCells = amap not cells
-- find the largest contiguous region of cells in the cave.
candidates
= maximumBy (compare `on` length)
$ fromMaybe (error "No regions generated! this should never happen.")
$ fromNullable
$ regions placeableCells
