1 module Sim ( initSimSpace, testSim, physStep, updateWaterChunk, validDirects ) where
4 import Data.Vector ((!), (//))
5 import qualified Data.Vector as V
7 data Simulation = Simulation
8 { simSpace :: V.Vector ChunkData
15 | Wall deriving (Show, Enum)
17 data ChunkData = ChunkData
18 { chunkType :: ChunkType
22 simGet Simulation{simSpace=s,simW=w} x y = s ! (y*w+x)
23 simSet sim@Simulation{simSpace=s,simW=w,simH=h} c x y = sim { simSpace = (s // [(y*w+x,c)]) }
24 simGetChunkType sim x y = chunkType $ simGet sim x y
26 initSimSpace x y = Simulation
27 { simSpace = V.replicate (y*x) ChunkData { chunkType=Air }
32 testSim = simSet (initSimSpace 3 3) (ChunkData Water) 1 1
34 physStep sim@Simulation{simW=w,simH=h} = _physStep [(x, y) | x <- [0..w-1], y <- [0..h-1]] sim sim
35 -- _physStep grid acc sim@Simulation{simSpace=s,simW=w,simH=h} | trace ("" ++ show acc) False = undefined
36 _physStep grid acc sim@Simulation{simSpace=s,simW=w,simH=h} =
38 else _physStep (tail grid) next sim
39 where x = fst $ head grid
41 valid = validDirects x y w h
42 next = case simGetChunkType sim x y of
43 Water -> updateWaterChunk x y valid acc
46 -- takes in list of valid chunks, as well as the sim to modify
47 updateWaterChunk x y valid sim =
48 -- if the chunk below is free, fall straight down
49 if elem (0,-1) valid && fromEnum (simGetChunkType sim x (y-1)) == fromEnum Air
51 let moved = simSet sim ChunkData { chunkType=Air } x y
52 in simSet moved ChunkData { chunkType=Water } x (y-1)
53 else if elem (-1,-1) valid && fromEnum (simGetChunkType sim (x-1) (y-1)) == fromEnum Air
55 let moved = simSet sim ChunkData { chunkType=Air } x y
56 in simSet moved ChunkData { chunkType=Water } (x-1) (y-1)
57 else if elem (1,-1) valid && fromEnum (simGetChunkType sim (x+1) (y-1)) == fromEnum Air
59 let moved = simSet sim ChunkData { chunkType=Air } x y
60 in simSet moved ChunkData { chunkType=Water } (x+1) (y-1)
64 -- gets chunks around a given chunk that are inside grid
65 validDirects x y w h = filter
66 (\q -> 0 <= (fst q) && (fst q) < w && (snd q) <= 0 && (snd q) < h)
67 [(a-x,b-y) | a <- [x-1..x+1], b <- [y-1..y+1], not (a==x && b==y)]