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|
{-# LANGUAGE NondecreasingIndentation #-}
{-# LANGUAGE OverloadedStrings #-}
module Wavefront where
import qualified Data.ByteString.Lazy.Char8 as L
import qualified Data.ByteString.Char8 as S
import Data.ByteString.Internal as BS
import Data.Char
import Data.IntMap (IntMap)
import qualified Data.IntMap as IntMap
import Data.ByteString.Lex.Fractional as F
import Data.ByteString.Lex.Integral as I
data ObjBuilder m = ObjBuilder
{ vertex :: [Double] -> m ()
, vertexT :: [Double] -> m ()
, vertexN :: [Double] -> m ()
, vertexP :: [Double] -> m ()
, face :: [RefTriple] -> m ()
, cstype :: Bool -> CSType -> m ()
, curv2 :: [Int] -> m ()
, curv :: Double -> Double -> [Int] -> m ()
, parm :: ParamSpec -> [Double] -> m ()
, specialPoints :: [Int] -> m ()
, endFreeForm :: m ()
, ctech :: CurveSamplingSpec -> m ()
, stech :: SurfaceSamplingSpec -> m ()
, deg :: [Int] -> m ()
, surf :: Double -> Double -> Double -> Double -> [RefTriple] -> m ()
, trim :: [CurveSpec] -> m ()
, hole :: [CurveSpec] -> m ()
, specialCurves :: [CurveSpec] -> m ()
, equivalentCurves :: [EmbeddedCurve] -> m ()
, groups :: [S.ByteString] -> m ()
, smoothingGroup :: Int -> m ()
, mergingGroup :: Int -> Double -> m ()
, usemtl :: S.ByteString -> m ()
, deprecated_cdc :: [Int] -> m ()
, deprecated_bzp :: [Int] -> m ()
, mtllib :: [S.ByteString] -> m ()
, objectName :: S.ByteString -> m ()
, badToken :: L.ByteString -> m ()
}
data CurveSamplingSpec
-- ctech cparm
= UniformSubdivision
{ divisionsPerCurveDegree :: Double -- ^ This really ought to be an integer but
-- but examples show floats. The only way
-- it makes sense as a float is if we are to
-- convert to an integer *after* multiplying
-- by the curve degree.
}
-- ctech cspace
| MaxLengthPolygonal { maxPolygonEdgeLength :: Double }
-- ctech curv
| CurvatureBasedPolygon { maxDistanceToCurve :: Double, maximumDegreesPerSample :: Double }
deriving (Eq,Show)
data SurfaceSamplingSpec
-- stech cparma ures vres
= UniformIsoparametric { uDivisionsPerDegree :: Double, vDivisionsPerDegree :: Double }
-- stech cparmb uvres
| UniformAfterTrimming { uvDivisionsPerDegree :: Double }
-- stech cspace maxlength
| MaxLengthPolytopal { maxPolytopEdgeLength :: Double }
-- stech curv maxdist maxangle
| CurvatureBasedPolytope { maxDistanceToSurface :: Double, maxDegreesPerCorner :: Double }
deriving (Eq,Show)
data ObjState = ObjState
{
}
newtype ObjConfig = ObjConfig
{ cfgSubst :: IntMap L.ByteString
}
-- consChunk :: S.ByteString -> L.ByteString -> L.ByteString
-- consChunk c bs = L.fromChunks (c : L.toChunks bs)
reappend :: ByteString -> ByteString -> Maybe ByteString
reappend a b =
let (ap,ao,al) = BS.toForeignPtr a
(bp,bo,bl) = BS.toForeignPtr b
in if ap == bp && ao+al == bo
then Just $ BS.PS ap ao (al+bl)
else Nothing
reconsChunk :: S.ByteString -> L.ByteString -> L.ByteString
reconsChunk b bs = case L.toChunks bs of
(c:cs) -> case reappend b c of
Just x -> L.fromChunks (x:cs)
Nothing -> L.fromChunks (b:c:cs)
_ -> L.fromChunks [b]
findToken :: ObjConfig -> L.ByteString -> L.ByteString
findToken (ObjConfig args) bs = case L.dropWhile (\c -> isSpace c || c=='\\') bs of
cs -> case L.uncons cs of
Just ('#',comment) -> findToken (ObjConfig args) $ L.drop 1 $ L.dropWhile (/='\n') comment
Just ('$',ref) -> case L.splitAt 5 ref of
(refp,ds) -> case I.readDecimal (L.toStrict refp) of
Just (i,es) -> case IntMap.lookup i args of
Just val -> val <> reconsChunk es ds
_ -> reconsChunk es ds
_ -> cs
Just _ -> cs
Nothing -> L.empty
{-
1 x bevel
2 x bmat
3 bzp
4 x call
5 cdc
6 x c_interp
7 con
8 x csh -- for all except these,
9 cstype -- Two chars suffice to distinguish
10 ctech
11 curv2 -- for all except these,
12 curv -- Two chars suffice to distinguish
13 deg
14 x d_interp
15 end
16 f
17 g
18 hole
19 x lod
20 x maplib
21 mg
22 mtllib
23 o
24 parm
25 s
26 scrv
27 x shadow_obj
28 sp
29 stech -- for all except these,
30 x step -- Two chars suffice to distinguish
31 surf
32 x trace_obj -- for all except these,
33 trim -- Two chars suffice to distinguish
34 x usemap -- for all except these,
35 usemtl -- Two chars suffice to distinguish
36 v
37 vn
38 vp
39 vt
-}
nextToken :: (L.ByteString -> L.ByteString) -> L.ByteString -> L.ByteString
nextToken tok bs = tok $ L.dropWhile (not . isSpace) bs
parseFloats tok bs cont = case L.splitAt 10 (tok bs) of
(ds,bs') -> case F.readSigned F.readExponential (L.toStrict ds) of
Just (x,b) -> parseFloats tok (reconsChunk b bs') (cont . (x :))
Nothing -> cont [] (ds <> bs')
parseFloatsN 0 _ bs cont = cont [] bs
parseFloatsN n tok bs cont = case L.splitAt 10 (tok bs) of
(ds,bs') -> case F.readSigned F.readExponential (L.toStrict ds) of
Just (x,b) -> parseFloatsN (n-1) tok (reconsChunk b bs') (cont . (x :))
Nothing -> cont [] (ds <> bs')
parseInts tok bs cont = case L.splitAt 5 (tok bs) of
(ds,bs') -> case I.readSigned I.readDecimal (L.toStrict ds) of
Just (x,b) -> parseInts tok (reconsChunk b bs') (cont . (x :))
Nothing -> cont [] (ds <> bs')
parseIntsN 0 tok bs cont = cont [] bs
parseIntsN n tok bs cont = case L.splitAt 5 (tok bs) of
(ds,bs') -> case I.readSigned I.readDecimal (L.toStrict ds) of
Just (x,b) -> parseIntsN (n-1) tok (reconsChunk b bs') (cont . (x :))
Nothing -> cont [] (ds <> bs')
parseTriples :: (L.ByteString -> L.ByteString) -> L.ByteString -> ([RefTriple] -> L.ByteString -> b) -> b
parseTriples tok bs cont = case L.splitAt 17 (tok bs) of
(ds,bs') -> case I.readSigned I.readDecimal (L.toStrict ds) of
Just (v,b) -> case S.splitAt 1 b of
("/",ds') -> case I.readSigned I.readDecimal ds' of
Just (vt,c) -> case S.splitAt 1 c of
("/",ds'') -> case I.readSigned I.readDecimal ds'' of
Just (vn,d) -> parseTriples tok (reconsChunk d bs') $ cont . (RefTriple v (Just vt) (Just vn) :)
Nothing -> parseTriples tok (reconsChunk ds'' bs') $ cont . (RefTriple v (Just vt) Nothing :)
_ -> parseTriples tok (reconsChunk c bs') $ cont . (RefTriple v (Just vt) Nothing :)
Nothing -> case S.splitAt 1 ds' of
("/",ds'') -> case I.readSigned I.readDecimal ds'' of
Just (vn,d) -> parseTriples tok (reconsChunk d bs') $ cont . (RefTriple v Nothing (Just vn) :)
Nothing -> parseTriples tok (reconsChunk ds'' bs') $ cont . (RefTriple v Nothing Nothing :)
_ -> parseTriples tok (reconsChunk ds' bs') $ cont . (RefTriple v Nothing Nothing :)
_ -> parseTriples tok (reconsChunk b bs') $ cont . (RefTriple v Nothing Nothing :)
Nothing -> cont [] (ds <> bs')
parseCurveSpecs :: (L.ByteString -> L.ByteString) -> L.ByteString -> ([CurveSpec] -> L.ByteString -> b) -> b
parseCurveSpecs tok bs cont = parseFloatsN 2 tok bs $ \fs bs' -> case fs of
(u0:u1:_) -> do
parseIntsN 1 tok bs' $ \is bs'' -> case is of
(i:_) -> parseCurveSpecs tok bs'' $ cont . (CurveSpec u0 u1 i :)
_ -> cont [] bs''
_ -> cont [] bs'
parseCurveSpecsN :: Int -> (L.ByteString -> L.ByteString) -> L.ByteString -> ([CurveSpec] -> L.ByteString -> b) -> b
parseCurveSpecsN 0 tok bs cont = cont [] bs
parseCurveSpecsN n tok bs cont = parseFloatsN 2 tok bs $ \fs bs' -> case fs of
(u0:u1:_) -> do
parseIntsN 1 tok bs' $ \is bs'' -> case is of
(i:_) -> parseCurveSpecsN (n-1) tok bs'' $ cont . (CurveSpec u0 u1 i :)
_ -> cont [] bs''
_ -> cont [] bs'
parseEmbeddedCurves :: (L.ByteString -> L.ByteString) -> L.ByteString -> ([EmbeddedCurve] -> L.ByteString -> b) -> b
parseEmbeddedCurves tok bs cont = parseIntsN 1 tok bs $ \is bs' -> case is of
(sref:_) -> do
parseCurveSpecsN 1 tok bs' $ \cs bs'' -> case cs of
(c:_) -> parseEmbeddedCurves tok bs'' $ cont . (EmbeddedCurve sref c :)
_ -> cont [] bs''
_ -> cont [] bs'
data CSType = Bmatrix | Bezier | Bspline | Cardinal | Taylor
deriving (Eq,Ord,Show,Enum)
data ParamSpec = ParamU | ParamV
deriving (Eq,Ord,Show,Enum)
data RefTriple = RefTriple
{ refV :: Int
, refT :: Maybe Int
, refN :: Maybe Int
}
-- data RefTriple = RefTriple Int (Maybe Int) (Maybe Int)
deriving (Eq,Ord,Show)
data CurveSpec = CurveSpec
{ curveStart :: Double
, curveEnd :: Double
, curveRef :: Int
}
deriving (Eq,Ord,Show)
data EmbeddedCurve = EmbeddedCurve
{ curveSurfaceRef :: Int
, embeddedCurve :: CurveSpec
}
deriving (Eq,Ord,Show)
lengthLessThan :: Int -> L.ByteString -> Bool
lengthLessThan n bs =
foldr (\c ret ac -> let m = S.length c in if ac <= m then False else ret $! ac - m)
(const True)
(L.toChunks bs)
n
parseOBJ :: Monad m => ObjBuilder m -> ObjConfig -> L.ByteString -> m ()
parseOBJ builder args bs0
| lengthLessThan 2 bs = return ()
| isSpace (L.index bs 1) = case L.head bs of
'f' -> parseT face 2
'g' -> case L.break (=='\n') $ L.drop 1 bs of -- Newline required to terminate group name list.
(gn,bs') -> do
groups builder (map L.toStrict $ L.words gn)
parseOBJ builder args bs'
's' -> case next 1 bs of
tok -> parseOffOrNumber tok $ \sg bs' -> do
smoothingGroup builder sg
parseOBJ builder args bs'
'v' -> parseV vertex 2
'o' -> -- o object-name
case L.break (=='\n') $ findToken args $ L.drop 1 bs of
(objn,bs') -> do
objectName builder (L.toStrict objn)
parseOBJ builder args bs'
_ -> badToken builder bs
| otherwise = case L.take 2 bs of
"vt" -> parseV vertexT 3
"vn" -> parseV vertexN 3
"vp" -> parseV vertexP 3
"bz" -> parseI deprecated_bzp 4 -- bzp
"cd" -> parseI deprecated_cdc 4 -- cdc
"co" -> -- con
parseEmbeddedCurves (findToken args) (next 2 bs) $ \ss bs' -> do
equivalentCurves builder ss
parseOBJ builder args bs'
"cs" -> -- cstype
let parseRat = parseChar 'r'
parseTyp tok cont | lengthLessThan 3 tok = badToken builder tok
| otherwise = case L.index tok 2 of
'a' -> cont Bmatrix $ next 3 tok
'z' -> cont Bezier $ next 3 tok
'p' -> cont Bspline $ next 3 tok
'r' -> cont Cardinal $ next 3 tok
'y' -> cont Taylor $ next 3 tok
_ -> badToken builder tok
in parseRat (next 2 bs) $ \isRat bs' -> do
parseTyp bs' $ \typ bs'' -> do
cstype builder isRat typ
parseOBJ builder args bs''
"ct" -> -- ctech
let tok = next 2 bs
in if lengthLessThan 2 tok
then badToken builder tok
else case L.index tok 1 of
'p' -> -- cparm
parseFloats (findToken args) (next 2 tok) $ \is bs' -> do
let x:_ = is ++ [0]
ctech builder (UniformSubdivision x)
parseOBJ builder args bs'
's' -> -- cspace
parseFloats (findToken args) (next 2 tok) $ \fs bs' -> do
let x:_ = fs ++ [1.0]
ctech builder (MaxLengthPolygonal x)
parseOBJ builder args bs'
'u' -> -- curv
parseFloats (findToken args) (next 2 tok) $ \fs bs' -> do
let δ:θ:_ = fs ++ repeat 1.0
ctech builder (CurvatureBasedPolygon δ θ)
parseOBJ builder args bs'
_ -> badToken builder tok
"cu" -> if lengthLessThan 5 bs
then badToken builder bs
else if L.index bs 4 == '2'
then parseI curv2 5 -- curv2
else do -- curv
parseFloatsN 2 (findToken args) (L.drop 4 bs) $ \vs bs' ->
parseInts (findToken args) bs' $ \is bs'' -> do
let u0:v0:_ = vs ++ repeat 0.0
curv builder u0 v0 is
parseOBJ builder args bs''
"de" -> parseI deg 3
"en" -> do endFreeForm builder
parseOBJ builder args (next 2 bs)
"ho" -> -- hole
parseCurveSpecs (findToken args) (next 2 bs) $ \ss bs' -> do
hole builder ss
parseOBJ builder args bs'
"mg" -> case next 2 bs of
tok -> parseOffOrNumber tok $ \mg bs' -> do
parseFloatsN 1 (findToken args) bs' $ \fs bs'' -> do
mergingGroup builder mg (head $ fs ++ [0])
parseOBJ builder args bs''
"pa" -> parseChar 'u' (next 2 bs) $ \isU bs' -> do
parseFloats (findToken args) (if isU then bs' else L.drop 1 bs') $ \vs bs'' -> do
parm builder (if isU then ParamU else ParamV) vs
parseOBJ builder args bs''
"sc" -> -- scrv
parseCurveSpecs (findToken args) (next 2 bs) $ \ss bs' -> do
specialCurves builder ss
parseOBJ builder args bs'
"sp" -> parseI specialPoints 3
"st" -> -- stech
let tok = next 2 bs
in if lengthLessThan 2 tok
then badToken builder tok
else case L.index tok 1 of
'p' -> -- cparma/cparmb
if lengthLessThan 6 tok
then badToken builder tok
else if L.index tok 5 == 'b'
then -- cparmb
parseFloats (findToken args) (next 5 tok) $ \is bs' -> do
let x:_ = is ++ [0]
stech builder (UniformAfterTrimming x)
parseOBJ builder args bs'
else -- cparma
parseFloats (findToken args) (next 5 tok) $ \is bs' -> do
let x:y:_ = is ++ [0]
stech builder (UniformIsoparametric x y)
parseOBJ builder args bs'
's' -> -- cspace
parseFloats (findToken args) (next 2 tok) $ \fs bs' -> do
let x:_ = fs ++ [1.0]
stech builder (MaxLengthPolytopal x)
parseOBJ builder args bs'
'u' -> -- curv
parseFloats (findToken args) (next 2 tok) $ \fs bs' -> do
let δ:θ:_ = fs ++ repeat 1.0
stech builder (CurvatureBasedPolytope δ θ)
parseOBJ builder args bs'
_ -> badToken builder tok
"su" -> -- surf
parseFloatsN 4 (findToken args) (next 2 bs) $ \fs bs' -> do
parseTriples (findToken args) bs' $ \ts bs'' -> do
let u0:u1:v0:v1:_ = fs ++ repeat 0
surf builder u0 u1 v0 v1 ts
parseOBJ builder args bs''
"tr" -> -- trim
parseCurveSpecs (findToken args) (next 2 bs) $ \ss bs' -> do
trim builder ss
parseOBJ builder args bs'
"us" -> -- usemtl
case L.break isSpace $ next 2 bs of
(mtl,bs') -> do
usemtl builder (L.toStrict mtl)
parseOBJ builder args bs'
"mt" -> -- mtllib
case L.break (=='\n') $ next 2 bs of
(fnn,bs') -> do
let slurp fnn = case L.break (=='.') fnn of
(fn,ext) | L.null (L.drop 1 ext) -> if L.null fn then []
else [fn]
| ".mtl" <- L.take 4 ext ->
if L.all isSpace (L.take 1 $ L.drop 4 ext)
then (fn <> ".mtl") : slurp (findToken args $ L.drop 4 ext)
else let f:fs = slurp (L.drop 3 ext) in (fn <> L.take 3 ext <> f) : fs
| otherwise -> let (f:fs) = slurp (L.drop 1 ext)
in (fn <> L.take 1 ext <> f) : fs
mtllib builder (map L.toStrict $ slurp fnn)
parseOBJ builder args bs'
-- TODO: call,csh,step,bmat,c_interp,d_interp,lod,shadow_obj,trace_obj,bevel
_ -> badToken builder bs
where
bs = findToken args bs0
next n xs = nextToken (findToken args) $ L.drop n xs
parseChar c tok cont = case L.uncons tok of
Just (x,cs) | x==c -> cont True $ next 0 cs
_ -> cont False tok
parseV build n = do
parseFloats (findToken args) (L.drop n bs) $ \vs bs' -> do
build builder vs
parseOBJ builder args bs'
parseI build n = do
parseInts (findToken args) (L.drop n bs) $ \vs bs' -> do
build builder vs
parseOBJ builder args bs'
parseT build n = do
parseTriples (findToken args) (L.drop n bs) $ \vs bs' -> do
build builder vs
parseOBJ builder args bs'
parseOffOrNumber tok cont = parseIntsN 1 (findToken args) tok $ \is bs' -> do
let (sg,bs'') = case is of
(i:_) -> (i,bs')
_ | lengthLessThan 2 tok -> (0,tok)
_ -> (if L.index tok 1 == 'f' then 0 else 1, next 1 tok)
cont sg bs''
|