diff --git a/src/Data/Xournal/BBox.hs b/src/Data/Xournal/BBox.hs
--- a/src/Data/Xournal/BBox.hs
+++ b/src/Data/Xournal/BBox.hs
@@ -14,27 +14,37 @@
 
 module Data.Xournal.BBox where
 
+import Control.Applicative 
 import Control.Monad
-import Data.ByteString hiding (map,maximum,minimum)
 -- import qualified Data.Sequence as Seq
 import Data.Xournal.Generic
 import Data.Xournal.Simple
+import Data.Xournal.Util
 import Data.Strict.Tuple 
 import qualified Data.Foldable as F
 import Data.Monoid
 import Prelude hiding (fst,snd)
 import qualified Prelude as Prelude (fst,snd)
 
+
+-- | bounding box type 
+
 data BBox = BBox { bbox_upperleft :: (Double,Double) 
                  , bbox_lowerright :: (Double,Double) } 
           deriving (Show,Eq)
 
-data StrokeBBox = StrokeBBox { strokebbox_tool :: ByteString
+-- | 
+
+data StrokeBBox = StrokeBBox { strokebbox_stroke :: Stroke 
+                             , strokebbox_bbox :: BBox } 
+                deriving (Show)
+  
+{-  
+  StrokeBBox { strokebbox_tool :: ByteString
                              , strokebbox_color :: ByteString 
                              , strokebbox_width :: Double
                              , strokebbox_data :: [Pair Double Double] 
-                             , strokebbox_bbox :: BBox }
-                deriving (Show)
+                             , strokebbox_bbox :: BBox } -}
 
 type TLayerBBox = GLayer [] StrokeBBox 
 
@@ -59,6 +69,14 @@
   in BBox{bbox_upperleft=(F.minimum xs, F.minimum ys)
          ,bbox_lowerright=(F.maximum xs, F.maximum ys)}
 
+bboxFromStroke :: Stroke -> BBox 
+bboxFromStroke (Stroke _ _ w dat) = inflate (mkbbox dat) w
+bboxFromStroke (VWStroke _ _ dat) = 
+  let dat' = map ((,) <$> fst3 <*> snd3) dat 
+      widthmax = F.maximum (map trd3 dat)
+  in inflate (mkbboxF dat') widthmax
+   
+
 dimToBBox :: Dimension -> BBox 
 dimToBBox (Dim w h) = BBox (0,0) (w,h)
 
@@ -67,6 +85,11 @@
 xformBBox :: ((Double,Double) -> (Double,Double)) -> BBox -> BBox 
 xformBBox f (BBox c1 c2) = BBox (f c1) (f c2)
 
+-- |
+
+inflate :: BBox -> Double -> BBox 
+inflate (BBox (x1,y1) (x2,y2)) r = BBox (x1-r,y1-r) (x2+r,y2+r)
+
 -- | 
 
 moveBBoxToOrigin :: BBox -> BBox 
@@ -90,12 +113,6 @@
       y6 = min y2 y4
   return (BBox (x5,y5) (x6,y6))
   
-{- 
-  let x5 = if x1 <= x3 && x2 <= x3  && xthen x3 else x1
-      y5 = if y1 < y3 then y3 else y1
-      x6 = if x2 < x4 then x2 else x4
-      y6 = if y2 < y4 then y2 else y4
-  in BBox (x5,y5) (x6,y6) -}
      
 unionBBox :: BBox -> BBox -> BBox
 unionBBox (BBox (x1,y1) (x2,y2)) (BBox (x3,y3) (x4,y4)) = 
@@ -142,7 +159,7 @@
   
 instance Maybeable IntersectBBox where
   type ElemType IntersectBBox = BBox
-  toMaybe (Intersect Bottom) = Nothing  -- error "empty intersectbbox"
+  toMaybe (Intersect Bottom) = Nothing  
   toMaybe (Intersect Top) = Nothing 
   toMaybe (Intersect (Middle x)) = Just x 
   fromMaybe Nothing = Intersect Top 
@@ -150,7 +167,7 @@
   
 instance Maybeable UnionBBox where
   type ElemType UnionBBox = BBox
-  toMaybe (Union Bottom) = Nothing -- error "empty unionbbox"
+  toMaybe (Union Bottom) = Nothing 
   toMaybe (Union Top) = Nothing 
   toMaybe (Union (Middle x)) = Just x 
   fromMaybe Nothing = Union Top 
@@ -159,27 +176,11 @@
 
 mkStrokeBBoxFromStroke :: Stroke -> StrokeBBox
 mkStrokeBBoxFromStroke str = 
-  StrokeBBox { strokebbox_tool = stroke_tool str 
-             , strokebbox_color = stroke_color str 
-             , strokebbox_width = stroke_width str 
-             , strokebbox_data = stroke_data str 
-             , strokebbox_bbox = mkbbox (stroke_data str) } 
+  StrokeBBox { strokebbox_stroke = str 
+             , strokebbox_bbox = bboxFromStroke str
+             } 
 
 strokeFromStrokeBBox :: StrokeBBox -> Stroke 
-strokeFromStrokeBBox strbbox = 
-  Stroke { stroke_tool = strokebbox_tool strbbox
-         , stroke_color = strokebbox_color strbbox
-         , stroke_width= strokebbox_width strbbox
-         , stroke_data = strokebbox_data strbbox } 
-
-
-{-
-data XournalBBox = XournalBBox { xojbbox_pages :: [PageBBox] }
-
-data PageBBox = PageBBox { pagebbox_dim :: Dimension
-                         , pagebbox_bkg :: Background
-                         , pagebbox_layers :: [LayerBBox] } 
+strokeFromStrokeBBox = strokebbox_stroke 
 
-data LayerBBox = LayerBBox { layerbbox_strokes :: [StrokeBBox] } 
--}
 
diff --git a/src/Data/Xournal/Generic.hs b/src/Data/Xournal/Generic.hs
--- a/src/Data/Xournal/Generic.hs
+++ b/src/Data/Xournal/Generic.hs
@@ -70,6 +70,8 @@
 
 type TXournalSimple = GXournal [] TPageSimple 
 
+-- |
+
 class GStrokeable a where
   gFromStroke :: Stroke -> a 
   gToStroke :: a -> Stroke 
@@ -78,6 +80,7 @@
   gFromStroke = id
   gToStroke = id 
 
+-- |
 
 class GListable s where  
   gFromList :: [a] -> s a 
@@ -91,6 +94,7 @@
   gFromList = Data.IntMap.fromList . zip [0..] 
   gToList = Data.IntMap.elems 
 
+-- |
 
 class GBackgroundable b where
   gFromBackground :: Background -> b 
@@ -100,9 +104,13 @@
   gFromBackground = id 
   gToBackground = id
 
+-- |
+  
 fromLayer :: (GStrokeable a, GListable s) => Layer -> GLayer s a 
 fromLayer = GLayer . gFromList . fmap gFromStroke . layer_strokes 
 
+-- |
+
 fromPage :: (GStrokeable a, GBackgroundable b, 
              GListable s, GListable s') => 
             Page -> GPage b s' (GLayer s a)  
@@ -111,6 +119,7 @@
                  ls =  gFromList . fmap fromLayer . page_layers $ p 
              in  GPage dim bkg ls 
 
+-- |
 
 class SListable m where
   chgStreamToList :: (GListable s) => m s a -> m [] a 
@@ -124,48 +133,69 @@
 instance SListable GXournal where
   chgStreamToList (GXournal t ps) = GXournal t (gToList ps)
   
+-- |
+
 g_title :: GXournal s a :-> ByteString 
 g_title = lens gtitle (\a f -> f { gtitle = a } )
 
+-- |
 g_pages :: GXournal s a :-> s a 
 g_pages = lens gpages (\a f -> f { gpages = a } )
 
+-- |
+
 g_dimension :: GPage b s a :-> Dimension 
 g_dimension = lens gdimension (\a f -> f { gdimension = a } )
 
+-- |
+
 g_background :: GPage b s a :-> b 
 g_background = lens gbackground (\a f -> f { gbackground = a } ) 
 
+-- |
+
 g_layers :: GPage b s a :-> s a 
 g_layers = lens glayers (\a f -> f { glayers = a } ) 
 
+-- |
+
 g_strokes :: GLayer s a :-> s a 
 g_strokes = lens gstrokes (\a f -> f { gstrokes = a } )
 
+-- |
+
 g_bstrokes :: GLayerBuf b s a :-> s a 
 g_bstrokes = lens gbstrokes (\a f -> f { gbstrokes = a } )
 
+-- |
+
 g_buffer :: GLayerBuf b s a :-> b 
 g_buffer = lens gbuffer (\a f -> f { gbuffer = a } )
 
+-- |
+
 g_selectTitle :: GSelect a b :-> ByteString
 g_selectTitle = lens gselectTitle (\a f -> f {gselectTitle = a})
 
+-- |
+
 g_selectAll :: GSelect a b :-> a 
 g_selectAll = lens gselectAll (\a f -> f {gselectAll = a} )
 
+-- |
+
 g_selectSelected :: GSelect a b :-> b
 g_selectSelected = lens gselectSelected (\a f -> f {gselectSelected = a})
 
-
-
-
+-- |
 
 toLayer :: (GStrokeable a, GListable s) => GLayer s a -> Layer
 toLayer = layerFromTLayerSimple . fmap gToStroke . chgStreamToList 
 
+-- |
+
 toNoBufferLayer :: GLayerBuf b s a -> GLayer s a 
-toNoBufferLayer (GLayerBuf b s) = GLayer s 
+toNoBufferLayer (GLayerBuf _b s) = GLayer s 
 
 
 toPage :: (GStrokeable a, GBackgroundable b, GListable s, GListable s', Functor s') => 
diff --git a/src/Data/Xournal/Predefined.hs b/src/Data/Xournal/Predefined.hs
--- a/src/Data/Xournal/Predefined.hs
+++ b/src/Data/Xournal/Predefined.hs
@@ -18,6 +18,13 @@
 
 import Text.Printf 
 
+-- | 
+
+predefinedPenShapeAspectXY :: (Double,Double)
+predefinedPenShapeAspectXY = (cos (pi/6.0), sin (pi/6.0))
+
+-- | 
+
 hexToRGBA :: Integer -> (Double,Double,Double,Double) 
 hexToRGBA n = 
   let r = n `div` (256*256*256)
@@ -72,7 +79,7 @@
 predefined_fine = 0.85
 
 predefined_medium :: Double
-predefined_medium = 1.41
+predefined_medium = 1.41 
 
 predefined_thick :: Double
 predefined_thick = 2.26
@@ -80,6 +87,9 @@
 predefined_verythick :: Double 
 predefined_verythick = 5.67
 
+predefined_ultrathick :: Double 
+predefined_ultrathick = 15.41
+
 ---- for Highlighter
 
 predefined_highlighter_veryfine :: Double
@@ -97,6 +107,10 @@
 predefined_highlighter_verythick :: Double 
 predefined_highlighter_verythick = 19.84
 
+predefined_highlighter_ultrathick :: Double 
+predefined_highlighter_ultrathick = 30.84
+
+
 ---- for Eraser
 
 predefined_eraser_veryfine :: Double
@@ -114,6 +128,8 @@
 predefined_eraser_verythick :: Double 
 predefined_eraser_verythick = 19.84
 
+predefined_eraser_ultrathick :: Double 
+predefined_eraser_ultrathick = 30.84
 
 
 
diff --git a/src/Data/Xournal/Select.hs b/src/Data/Xournal/Select.hs
--- a/src/Data/Xournal/Select.hs
+++ b/src/Data/Xournal/Select.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE TypeSynonymInstances, TypeOperators, FlexibleInstances, 
-             StandaloneDeriving, DeriveFunctor, DeriveFoldable, DeriveTraversable  #-}
+             StandaloneDeriving, DeriveFunctor, DeriveFoldable, 
+             DeriveTraversable  #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -11,6 +12,7 @@
 -- Stability   : experimental
 -- Portability : GHC
 --
+-----------------------------------------------------------------------------
 
 module Data.Xournal.Select where
 
@@ -39,11 +41,11 @@
 singletonSZ x = SZ (x, (empty,empty))
 
 lengthSZ :: SeqZipper a -> Int 
-lengthSZ (SZ (x, (x1s,x2s))) = length x1s + length x2s + 1 
+lengthSZ (SZ (_x, (x1s,x2s))) = length x1s + length x2s + 1 
 
 
 currIndex :: SeqZipper a -> Int
-currIndex (SZ (x, (x1s,x2s))) = length x1s 
+currIndex (SZ (_x, (x1s,_x2s))) = length x1s 
 
 appendGoLast :: SeqZipper a -> a -> SeqZipper a
 appendGoLast (SZ (y,(y1s,y2s))) x = SZ (x, ((y1s |> y) >< y2s, empty))
@@ -54,7 +56,7 @@
     EmptyL -> case viewl y2s of 
                 EmptyL -> Nothing 
                 z :< zs -> Just (SZ (z,(empty,zs)))
-    z :< zs -> Just (SZ (y,(zs,y2s)))
+    _z :< zs -> Just (SZ (y,(zs,y2s)))
     
 moveLeft :: SeqZipper a -> Maybe (SeqZipper a)
 moveLeft (SZ (x,(x1s,x2s))) = 
@@ -80,6 +82,7 @@
              | n > n_x1s = let (x2s1,x2s2) = splitAt (n-n_x1s-1) x2s
                                el :< rm = viewl x2s2
                            in Just (SZ (el, ((x1s |> x) >< x2s1, rm)))
+             | otherwise = error "error in moveTo"
   in result 
 
 goFirst :: SeqZipper a -> SeqZipper a 
@@ -106,11 +109,11 @@
 next = fmap current . moveRight
 
 replace :: a -> SeqZipper a -> SeqZipper a 
-replace y (SZ (x,zs)) = SZ (y,zs)
+replace y (SZ (_x,zs)) = SZ (y,zs)
 
 
 deleteCurrent :: SeqZipper a -> Maybe (SeqZipper a)
-deleteCurrent orig@(SZ (_,(xs,ys))) = 
+deleteCurrent (SZ (_,(xs,ys))) = 
   case viewl ys of 
     EmptyL -> case viewr xs of 
                 EmptyR -> Nothing 
@@ -126,7 +129,7 @@
 
 selectFirst :: ZipperSelect a -> ZipperSelect a 
 selectFirst (NoSelect []) = NoSelect []
-selectFirst (NoSelect lst@(x:xs))  = Select . gFromList $ lst
+selectFirst (NoSelect lst@(_:_))  = Select . gFromList $ lst
 selectFirst (Select (O Nothing)) = NoSelect []
 selectFirst (Select (O msz)) = Select . O $ return . goFirst =<<  msz
 
diff --git a/src/Data/Xournal/Simple.hs b/src/Data/Xournal/Simple.hs
--- a/src/Data/Xournal/Simple.hs
+++ b/src/Data/Xournal/Simple.hs
@@ -11,20 +11,17 @@
 -- Stability   : experimental
 -- Portability : GHC
 --
- 
+----------------------------------------------------------------------------- 
+
 module Data.Xournal.Simple where
 
+import Control.Applicative 
 import qualified Data.ByteString as S
-import Data.ByteString.Char8
+import Data.ByteString.Char8 hiding (map)
 import Data.Strict.Tuple
-
-import Control.Category
+import Data.Xournal.Util
 import Data.Label
-import Prelude hiding ((.),id,putStrLn)
-
-
-
-import Prelude hiding (fst,snd,curry,uncurry)
+import Prelude hiding ((.),id,putStrLn,fst,snd,curry,uncurry)
 
 type Title = S.ByteString
 
@@ -33,11 +30,19 @@
                      , stroke_width :: !Double
                      , stroke_data  :: ![Pair Double Double]
                      }
+            | VWStroke { stroke_tool :: S.ByteString 
+                       , stroke_color :: S.ByteString 
+                       , stroke_vwdata :: [(Double,Double,Double)] 
+                       }
             deriving Show
 
+
+
 data Dimension = Dim { dim_width :: !Double, dim_height :: !Double }
                deriving Show
 
+-- | 
+
 data Background = Background { bkg_type :: !S.ByteString 
                              , bkg_color :: !S.ByteString 
                              , bkg_style :: !S.ByteString 
@@ -49,28 +54,44 @@
                                 }
                 deriving Show 
 
+-- | 
+
 data Xournal = Xournal { xoj_title :: !Title, xoj_pages :: ![Page] }
              deriving Show 
 
+-- | 
+
 data Page = Page { page_dim :: !Dimension
                  , page_bkg :: !Background 
                  , page_layers :: ![Layer] }
           deriving Show 
 
+-- | 
+
 data Layer = Layer { layer_strokes :: ![Stroke] } 
            deriving Show 
 
+-- | 
+
+getXYtuples :: Stroke -> [(Double,Double)]
+getXYtuples (Stroke _t _c _w d) = map (\(x :!: y) -> (x,y)) d
+getXYtuples (VWStroke _t _c d) = map ((,)<$>fst3<*>snd3) d 
+
+-- | 
+
 s_tool :: Stroke :-> ByteString
 s_tool = lens stroke_tool (\a f -> f { stroke_tool = a })  
 
+-- | 
+
 s_color :: Stroke :-> ByteString 
 s_color = lens stroke_color (\a f -> f { stroke_color = a } )
 
-s_width :: Stroke :-> Double 
-s_width = lens stroke_width (\a f -> f { stroke_width = a } )
+-- s_width :: Stroke :-> Double 
+-- s_width = lens stroke_width (\a f -> f { stroke_width = a } )
 
-s_data :: Stroke :-> [Pair Double Double] 
-s_data = lens stroke_data (\a f -> f { stroke_data = a } )
+-- s_data :: Stroke :-> [Pair Double Double] 
+-- s_data = lens stroke_data (\a f -> f { stroke_data = a } )
 
 s_title :: Xournal :-> Title
 s_title = lens xoj_title (\a f -> f { xoj_title = a } )
diff --git a/src/Data/Xournal/Util.hs b/src/Data/Xournal/Util.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Xournal/Util.hs
@@ -0,0 +1,29 @@
+-----------------------------------------------------------------------------
+-- |
+-- Module      : Data.Xournal.Util
+-- Copyright   : (c) 2011, 2012 Ian-Woo Kim
+--
+-- License     : BSD3
+-- Maintainer  : Ian-Woo Kim <ianwookim@gmail.com>
+-- Stability   : experimental
+-- Portability : GHC
+--
+-----------------------------------------------------------------------------
+
+module Data.Xournal.Util where
+
+-- |
+
+fst3 :: (a,b,c) -> a
+fst3 (x,_,_) = x 
+
+-- |
+
+snd3 :: (a,b,c) -> b
+snd3 (_,y,_) = y 
+
+-- |
+
+trd3 :: (a,b,c) -> c
+trd3 (_,_,z) = z
+
diff --git a/xournal-types.cabal b/xournal-types.cabal
--- a/xournal-types.cabal
+++ b/xournal-types.cabal
@@ -1,5 +1,5 @@
 Name:		xournal-types
-Version:	0.3.2
+Version:	0.4
 Synopsis:	Data types for programs for xournal file format
 Description: 	Xournal file format data type including generic interface
 License: 	BSD3
@@ -34,6 +34,7 @@
                    Data.Xournal.Buffer
                    Data.Xournal.Predefined 
                    Data.Xournal.Select
+                   Data.Xournal.Util
   Other-Modules: