diff --git a/Geom2d.hs b/Geom2d.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d.hs
@@ -0,0 +1,17 @@
+module Geom2d
+  ( module Geom2d.Point
+  , module Geom2d.Line
+  , module Geom2d.Shape
+  , module Geom2d.Intersect
+  , module Geom2d.Distance
+  , module Geom2d.Translate
+  , module Geom2d.Rotation
+  ) where
+
+import Geom2d.Point
+import Geom2d.Line
+import Geom2d.Shape
+import Geom2d.Intersect
+import Geom2d.Distance
+import Geom2d.Translate
+import Geom2d.Rotation
diff --git a/Geom2d/Distance.hs b/Geom2d/Distance.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Distance.hs
@@ -0,0 +1,12 @@
+{-# LANGUAGE MultiParamTypeClasses #-}
+
+module Geom2d.Distance where
+
+import Geom2d.Point.Internal
+
+class Distance p q where
+  distance :: (Ord a, Floating a) => p a -> q a -> a
+
+instance Distance Point' Point' where
+  distance (Point' (a1,a2)) (Point' (b1,b2)) =
+    sqrt $ (a1 - b1)^(2::Int) + (a2 - b2)^(2::Int)
diff --git a/Geom2d/Intersect.hs b/Geom2d/Intersect.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Intersect.hs
@@ -0,0 +1,71 @@
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+
+module Geom2d.Intersect
+
+where
+
+import Geom2d.Point
+import Geom2d.Line
+import Geom2d.Line.Internal
+
+class Intersect a b where
+  intersect :: a -> b -> Bool
+
+instance (Eq a) => Intersect (Point' a) (Point' a) where
+  intersect p q = p == q
+
+instance (Eq (p a), Num (p a), Num a, RealFloat a, Point p) =>
+         Intersect (InfLine p a) (InfLine p a) where
+  intersect a b | a == b = True
+                | a `parallel` b = False
+                | otherwise = True
+
+instance (Point p, Eq a, Fractional a) =>
+         Intersect (InfLine p a) (p a) where
+  intersect line@(InfLine a _) q =
+    maybe
+    ( x a == x q )
+    ( \f -> f (x q) == y q )
+    ( lineF line )
+
+instance (Point p, Eq a, Fractional a) =>
+         Intersect (p a) (InfLine p a) where
+  intersect = flip intersect
+
+instance (Eq (p a), Point p, Num (p a), RealFloat a) =>
+         Intersect (FinLine p a) (FinLine p a) where
+  intersect (FinLine a1 b1) (FinLine a2 b2) =
+    case intersection (InfLine a1 b1) (InfLine a2 b2) of
+      Nothing -> False
+      Just p ->
+        let minx = max (min (x a1) (x b1)) (min (x a2) (x b2))
+            maxx = min (max (x a1) (x b1)) (max (x a2) (x b2))
+            miny = max (min (y a1) (y b1)) (min (y a2) (y b2))
+            maxy = min (max (y a1) (y b1)) (max (y a2) (y b2))
+        in and [ x p <= maxx
+               , x p >= minx
+               , y p <= maxy
+               , y p >= miny
+               ]
+
+instance (Eq (p a), Point p, Num (p a), RealFloat a) =>
+         Intersect (InfLine p a) (FinLine p a) where
+  intersect infLine (FinLine f1 f2) =
+    case intersection infLine (InfLine f1 f2) of
+      Nothing -> False
+      Just p ->
+        let minx = min (x f1) (x f2)
+            maxx = max (x f1) (x f2)
+            miny = min (y f1) (y f2)
+            maxy = max (y f1) (y f2)
+        in and [ x p <= maxx
+               , x p >= minx
+               , y p <= maxy
+               , y p >= miny
+               ]
+
+instance (Eq (p a), Point p, Num (p a), RealFloat a) =>
+         Intersect (FinLine p a) (InfLine p a) where
+  intersect = flip intersect
diff --git a/Geom2d/Line.hs b/Geom2d/Line.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Line.hs
@@ -0,0 +1,101 @@
+-- | This module describes what lines are defines functions to work
+-- with lines.
+module Geom2d.Line
+    ( -- * Infinite lines
+      InfLine
+    , mkInfLine
+    , lineF
+    , parallel
+    , slope
+    , root
+    , intersection
+    -- * Finite lines
+    , FinLine
+    , mkFinLine
+    , lineLength
+    )
+
+where
+
+import Geom2d.Point
+import Geom2d.Line.Internal
+
+-- | Construct an infinit line by specifiying two points.  We won't
+-- get a line when the given points are equal.
+mkInfLine :: (Eq (p a)) => p a -> p a -> Maybe (InfLine p a)
+mkInfLine a b
+    | a == b = Nothing
+    | otherwise = Just $ InfLine a b
+
+-- | Get a function describing the line.  We won't get a function if
+-- the line is vertical.
+lineF :: (Eq a, Fractional a, Point p) =>
+         InfLine p a -> Maybe (a -> a)
+lineF l@(InfLine p _) =
+    ( \m -> case root l of
+        Just x0 -> \arg -> m * (arg - x0)
+        Nothing -> const (y p) ) <$>
+    slope l
+
+-- | Check if two lines are paralllel to each other.  This function
+-- assumes lines parallel to themselves.
+parallel :: (Num a, Num (p a), Point p, Eq a) =>
+            InfLine p a -> InfLine p a -> Bool
+parallel (InfLine a b) (InfLine p q) = (b - a) `cross` (q - p) == 0
+
+-- | Calculate the slope of a line.  We won't get a value for the
+-- slope if, and only if, the line is vertical.
+slope :: (Fractional a, Point p, Eq a) =>
+         InfLine p a -> Maybe a
+slope (InfLine p q)
+  | x p == x q = Nothing
+  | otherwise = Just $ (y q - y p) / (x q - x p)
+
+-- | Calculate the point where a line meets the x-axis.  We won't get
+-- a value if, and only if the line is parallel to the x-axis.
+root :: (Eq a, Fractional a, Point p) =>
+        InfLine p a -> Maybe a
+root l@(InfLine p _) =
+  case slope l of
+    Nothing -> Just $ x p
+    Just m ->
+      if m == 0
+      then Nothing
+      else Just $ x p - (y p * m)
+
+-- | Calculate the point where two lines intersect.
+intersection :: (Eq (p a), Num (p a), RealFloat a, Point p) =>
+                InfLine p a -> InfLine p a -> Maybe (p a)
+intersection l1@(InfLine a1 _) l2@(InfLine b1 _)
+  | l1 == l2 = Nothing
+  | l1 `parallel` l2 = Nothing
+  | otherwise =
+      case slope l1 of
+        Nothing -> do
+          x0 <- root l1
+          f <- lineF l2
+          return (fromCoords x0 (f x0))
+        Just ma ->
+          case slope l2 of
+            Nothing -> do
+              x0 <- root l2
+              f <- lineF l1
+              return (fromCoords x0 (f x0))
+            Just mb -> do
+              let na = y a1 - ma * x a1
+                  nb = y b1 - mb * x b1
+                  safeDiv num denom | denom == 0 = Nothing
+                                    | otherwise = Just (num/denom)
+              x' <- (nb - na) `safeDiv` (ma - mb)
+              f <- lineF l1
+              return (fromCoords x' (f x'))
+
+-- | mkFinLine returns a valid finite line, if any.
+mkFinLine :: (Eq (p a)) => p a -> p a -> Maybe (FinLine p a)
+mkFinLine a b
+  | a == b = Nothing
+  | otherwise = Just (FinLine a b)
+
+-- | Get the length of a finite line.
+lineLength :: (Point p, Num (p a), Floating a) => FinLine p a -> a
+lineLength (FinLine a b) = magnitude (b - a)
diff --git a/Geom2d/Line/Internal.hs b/Geom2d/Line/Internal.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Line/Internal.hs
@@ -0,0 +1,111 @@
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+
+-- | This module defines the internals of a line.  You probably won't
+-- need this module when using the geomtry libary.
+
+module Geom2d.Line.Internal where
+
+import Test.QuickCheck
+import Data.Maybe
+import Data.AEq
+import Geom2d.Point
+import Geom2d.Translate
+import Geom2d.Distance
+import Control.Monad
+
+-- | This type modells a infinite line.
+data InfLine p a = InfLine (p a) (p a) deriving (Show, Read)
+
+-- | `InfLine` is a `Functor` where the function is mapped over both
+-- points which define the `InfLine`.
+instance Functor p => Functor (InfLine p) where
+  fmap f (InfLine a b) = InfLine (fmap f a) (fmap f b)
+
+-- | This `Arbitrary` instance should only produce valid `InfLine`s.
+instance (Eq (p a), Arbitrary (p a)) => Arbitrary (InfLine p a) where
+  arbitrary = do p1 <- arbitrary
+                 p2 <- arbitrary `suchThat` (/= p1)
+                 return $ InfLine p1 p2
+
+-- | Two lines are equal when they have the same root and the same
+-- slope.  If the two lines do not have a root, that means that the
+-- lines are parallel to the x-axis.  In this case we compare their
+-- y-value.
+instance (Eq (p a), Eq a, RealFloat a, Num (p a), Point p) =>
+         Eq (InfLine p a) where
+  a@(InfLine a1 _) == b@(InfLine b1 _)
+      -- If the slopes of the lines are not equal they cannot be the
+      -- equal themselves
+      | slope a /= slope b = False
+      -- When the slopes are vertical they should have the same x
+      -- component
+      | isNothing (slope a) = x a1 == x b1
+      | otherwise = case root a of
+                      Just _ -> fromMaybe False ( (==) <$> root a <*> root b )
+                      Nothing -> y a1 == y b1
+      where slope (InfLine m n) | x (n - m) == 0 = Nothing
+                                | otherwise = Just $ y (n - m) / x (n - m)
+            root l@(InfLine p q) | y p == y q = Nothing
+                                 | otherwise = 
+                                     (do dy <- slope l
+                                         return (x q - (y q / dy))) `mplus`
+                                     Just (x p)
+
+-- | Translate a line by a given vector.
+instance Translate p => Translate (InfLine p) where
+  translate m (InfLine p q) = InfLine (m `translate` p) (m `translate` q)
+
+-- | Modells a finite line stretching between two points.
+data FinLine p a = -- | We expect the two points to be different
+                   FinLine (p a) (p a) deriving (Show,Read)
+
+-- | Two lines are equal if their end points are equal.
+--
+-- prop> FinLine a b == FinLine b a
+instance (Eq (p a)) => Eq (FinLine p a) where
+  (FinLine a1 b1) == (FinLine a2 b2) =
+    (a1 == a2 && b1 == b2) ||
+    (a1 == b2 && b1 == a2)
+
+-- | This `Arbitrary` instance should only produce valid `FinLine`s.
+instance (Eq (p a), Arbitrary (p a)) => Arbitrary (FinLine p a) where
+  arbitrary = do p1 <- arbitrary
+                 p2 <- arbitrary `suchThat` (/= p1)
+                 return $ FinLine p1 p2
+
+-- | Translate a `FinLine` by a fiven vector
+instance Translate p => Translate (FinLine p) where
+  translate v (FinLine p q) = FinLine (v `translate` p) (v `translate` q)
+
+-- | Two lines are almost equal if their ending points are almost
+-- equal.
+instance AEq (p a) => AEq (FinLine p a) where
+  (FinLine a1 b1) ~== (FinLine a2 b2) =
+    (a1 ~== a2 && b1 ~== b2) ||
+    (a1 ~== b2 && b1 ~== a2)
+
+instance (Point p) =>
+         Distance (FinLine p) p where
+  distance (FinLine a b) p =
+    sqrt (dx*dx + dy*dy)
+    where dx = ax + (u * qx) - px
+          dy = ay + (u * qy) - py
+          qx = bx - ax
+          qy = by - ay
+          s = qx^(2::Int) + qy^(2::Int)
+          u' = ((px - ax)*qx + (py - ay)*qy)/s
+          u | u' > 1    = 1
+            | u' < 0    = 0
+            | otherwise = u'
+          py = y p
+          px = x p
+          ax = x a
+          ay = y a
+          bx = x b
+          by = y b
+
+instance (Point p) =>
+         Distance p (FinLine p) where
+  distance = flip distance
diff --git a/Geom2d/Point.hs b/Geom2d/Point.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Point.hs
@@ -0,0 +1,62 @@
+module Geom2d.Point
+    ( Point (..)
+    , Point'
+    , Triangle
+    , Scale (..)
+    , normalize
+    , magnitude
+    , dot
+    , cross
+    , triArea
+    , pointInTriangle
+    )
+
+where
+
+import Geom2d.Point.Internal
+
+type Triangle p = (p,p,p)
+
+infixl 7 `dot`,`cross`
+
+dot :: (Num a, Point p) => p a -> p a -> a
+dot a b = x a * x b + y a * y b
+
+cross :: (Num a, Point p) => p a -> p a -> a
+cross a b = x a * y b - y a * x b
+
+triArea :: (Point p, Num (p a), Fractional a) => Triangle (p a) -> a
+triArea (a,b,c) = abs $ ((b - a) `cross` (c - a)) / 2
+
+pointInTriangle :: (Eq (p a), Num (p a), Fractional a, Point p, Ord a) =>
+                   Triangle (p a) -> p a -> Bool
+pointInTriangle (a,b,c) p
+    -- barycentric coordinates
+    | b == a || c == a || b == c = False
+    | p == a = True
+    | otherwise = u >= 0 && v >= 0 && u + v <= 1
+    where
+      u = ( v1Square * v2v0 - v1v0 * v2v1 ) / denom
+      v = ( v0Square * v2v1 - v0v1 * v2v0 ) / denom
+      denom = v0Square * v1Square - v0v1 * v1v0
+      v1Square = v1 `dot` v1
+      v0Square = v0 `dot` v0
+      v1v0 = v1 `dot` v0
+      v0v1 = v0 `dot` v1
+      v2v0 = v2 `dot` v0
+      v2v1 = v2 `dot` v1
+      v0 = c-a
+      v1 = b-a
+      v2 = p-a
+
+class Scale p where
+  scale :: (Num a) => a -> p a -> p a
+
+instance Scale Point' where
+  scale s (Point' (a,b)) = Point' (a * s, b * s)
+
+-- | Normalizes a scaleable point to length 1.
+normalize :: (Scale p, Point p, Fractional a, Eq a, Floating a) =>
+             p a -> Maybe (p a)
+normalize v | magnitude v == 0 = Nothing
+            | otherwise = Just $ scale (1/magnitude v) v
diff --git a/Geom2d/Point/Internal.hs b/Geom2d/Point/Internal.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Point/Internal.hs
@@ -0,0 +1,62 @@
+module Geom2d.Point.Internal
+    ( Point' (..)
+    , Point (..)
+    , magnitude
+    )
+
+where
+
+import Data.AEq
+import Data.Fixed
+import Geom2d.Rotation
+import qualified Prelude ((^))
+import Prelude hiding ((^))
+import Test.QuickCheck
+
+(^) :: Num a => a -> Int -> a
+(^) = (Prelude.^)
+
+newtype Point' a = Point' (a,a) deriving (Show, Read, Eq)
+
+class Point p where
+  x :: p a -> a
+  y :: p a -> a
+  fromCoords :: a -> a -> p a
+
+magnitude :: (Point p, Floating a, Num a) => p a -> a
+magnitude p =
+  sqrt (x p ^ (2::Int) + y p ^ (2::Int))
+
+instance Point Point' where
+  x (Point' p) = fst p
+  y (Point' p) = snd p
+  fromCoords a b = Point' (a, b)
+
+instance (Eq a, Num a, Fractional a, RealFloat a) => Num (Point' a) where
+  (Point' (p1,p2)) + (Point' (q1,q2)) = Point' (p1+q1, p2+q2)
+  (Point' (p1,p2)) - (Point' (q1,q2)) = Point' (p1-q1, p2-q2)
+  (Point' (m,n)) * (Point' (p,q)) = Point' (m*p - n*q, m*q + n*p)
+  abs (Point' (m,n)) = Point' (sqrt (m^2 + n^2), 0)
+  signum p@(Point' (m,n))
+      | m == fromIntegral (0::Int) && n == fromIntegral (0::Int) =
+          Point' (m,n)
+      | otherwise = Point' (m*l,n*l)
+      where l = 1 / x (abs p)
+  fromInteger n = Point' (fromInteger n, 0)
+  negate (Point' (a,b)) = Point' (negate a, negate b)
+
+instance (Arbitrary a) => Arbitrary (Point' a) where
+  arbitrary = curry Point' <$> arbitrary <*> arbitrary
+
+instance (Num a, AEq a, RealFloat a) => AEq (Point' a) where
+  (Point' (m,n)) ~== (Point' (p,q)) =
+    m^2 + n^2 ~== p^2 + q^2 &&
+    atan2 n m ~== atan2 q p
+
+instance Functor Point' where
+  fmap f (Point' (a,b)) = Point' (f a, f b)
+
+instance Rotation Point' where
+  angle p | magnitude p == 0 = Nothing
+          | otherwise = Just $ atan2 (y p) (x p)
+  rotate r (Point' (a,b)) = Point' (a * cos r - b * sin r, a * sin r + b * cos r)
diff --git a/Geom2d/Rotation.hs b/Geom2d/Rotation.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Rotation.hs
@@ -0,0 +1,25 @@
+module Geom2d.Rotation
+
+where
+
+-- | Modells data that has an angle and can be rotated.  
+class Rotation p where
+  -- | An object can return the orientation in space.  If the object
+  -- returns its orientation it should hold the following law:
+  --
+  -- prop> fromMaybe True $ (==) <$> angle (r `rotate` x) <*> ((subtract pi).((`mod'` (2*pi)).(+pi).(+r)) <$> angle x)
+  --
+  -- Also angle should never return a value bigger than `pi` and
+  -- smaller than `- pi`
+  --
+  -- prop> fromMaybe True (fmap (\a -> a >= (- pi) && a <= pi) (angle x))
+  --
+  -- The default implementation is
+  -- 
+  -- @
+  -- angle _ = Nothing
+  -- @
+  angle :: (Floating a, RealFloat a, Ord a) => p a -> Maybe a
+  angle _ = Nothing
+  -- | Should rotate an object by a given angle.
+  rotate :: (Floating a) => a -> p a -> p a
diff --git a/Geom2d/Shape.hs b/Geom2d/Shape.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Shape.hs
@@ -0,0 +1,19 @@
+module Geom2d.Shape
+    ( Shape
+    , circle
+    , rectangle
+    )
+
+where
+
+import Geom2d.Point
+import Geom2d.Rotation
+import Geom2d.Shape.Internal
+import Geom2d.Translate
+
+circle :: Num a => p a -> a -> Shape p a
+circle m r = ShapeCircle $ mkCircleInt m r
+
+rectangle :: (Translate p, Eq a, RealFloat a, Point p, Rotation p) =>
+             p a -> a -> a -> Maybe (Shape p a)
+rectangle m a b = ShapePolygon <$> rectangleInt m a b
diff --git a/Geom2d/Shape/Internal.hs b/Geom2d/Shape/Internal.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Shape/Internal.hs
@@ -0,0 +1,214 @@
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+module Geom2d.Shape.Internal
+    ( Circle (..)
+    , mkCircleInt
+    , radius
+    , center
+    , Polygon (..)
+    , convexHull'
+    , rectangleInt
+    , Shape (..)
+    )
+
+       where
+
+import Data.Function
+import Data.List hiding (intersect)
+import Data.Maybe
+import Geom2d.Distance
+import Geom2d.Intersect
+import Geom2d.Line.Internal
+import Geom2d.Point
+import Geom2d.Point.Internal
+import Geom2d.Rotation
+import Geom2d.Translate
+import Test.QuickCheck
+
+data Circle p a = Circle (p a) a deriving (Show,Read,Eq)
+
+instance (Point p, Distance p p) => Distance (Circle p) p where
+  distance (Circle m r) p =
+    max (distance m p - r) 0
+
+instance (Point p, Distance p p) => Distance p (Circle p) where
+  distance = flip distance
+
+instance (Floating a, Ord a, Distance p p) =>
+         Intersect (Circle p a) (p a) where
+  intersect (Circle m r) p
+    | distance m p <= r = True
+    | otherwise = False
+
+instance (Floating a, Ord a, Distance p p) =>
+         Intersect (p a) (Circle p a) where
+  intersect = flip intersect
+
+instance (Floating a, Ord a, Distance p p) =>
+         Intersect (Circle p a) (Circle p a) where
+  intersect (Circle m1 r1) (Circle m2 r2) =
+    distance m1 m2 <= r1 + r2
+
+instance (Arbitrary a, Arbitrary (p a), Ord a, Num a) =>
+         Arbitrary (Circle p a) where
+  arbitrary = Circle <$> arbitrary <*>
+              (arbitrary `suchThat`(>0))
+
+instance (Rotation p, Point p) => Rotation (Circle p) where
+  angle (Circle m _) = angle m
+  rotate ang (Circle m r) = Circle (rotate ang m) r
+
+mkCircleInt :: (Num a) => p a -> a -> Circle p a
+mkCircleInt m r' = Circle m (abs r')
+
+radius :: Circle p a -> a
+radius (Circle _ r) = r
+
+center :: Circle p a -> p a
+center (Circle m _) = m
+
+-- | A Polygon is meant to describe a convex 2-dimensional shape.
+data Polygon p a =  -- | The point (first argument) should be inside
+                    -- the polygon, otherwise weird stuff will happen.
+                    -- Also you must not specify the same vector
+                    -- (second argument) twice.
+                   Polygon (p a) [p a]
+                   deriving (Show,Read,Eq)
+
+instance (Point p, Fractional a, Num (p a), Eq (p a), Ord a) =>
+         Intersect (p a) (Polygon p a) where
+  intersect p (Polygon m vs) =
+    any (`pointInTriangle` p) triangles
+    where triangles = map (\(a,b) -> (m,a,b))
+                      ( zip verteces (tail verteces ++ [head verteces]))
+          verteces = map (+ m) vs
+
+instance (Point p, Fractional a, Num (p a), Eq (p a), Ord a) =>
+         Intersect (Polygon p a) (p a) where
+  intersect = flip intersect
+
+instance ( Arbitrary (p a), Num (p a), RealFloat a, Point p, Scale p
+         , Eq (p a)) =>
+         Arbitrary (Polygon p a) where
+  arbitrary = do
+    vs' <- listOf1 (arbitrary `suchThat` (\a -> magnitude a > 0)) `suchThat`
+           ((>= 4).length)
+    (return.fromJust.convexHull') vs'
+
+instance (Eq (p a), Floating a, Num (p a), Ord a, Point p) =>
+         Intersect (Polygon p a) (Circle p a) where
+  intersect poly@(Polygon p vs') (Circle m r)
+    | m `intersect` poly = True
+    | otherwise =
+          any ((r >=). distance m)
+          verteces
+    where verteces = zipWith FinLine
+                     vs
+                     (tail vs ++ [head vs])
+          vs = map (p+) vs'
+
+instance (Eq (p a), Num (p a), RealFloat a, Point p) =>
+         Intersect (Polygon p a) (Polygon p a) where
+  intersect poly1@(Polygon p1 vs1) poly2@(Polygon p2 vs2) =
+    let verts1 = map (p1+) vs1
+        verts2 = map (p2+) vs2
+        edges1 = zipWith FinLine verts1 (tail verts1 ++ [head verts1])
+        edges2 = zipWith FinLine verts2 (tail verts2 ++ [head verts2])
+    in any (uncurry intersect)
+       [ (v1,v2) | v1 <- edges1, v2 <- edges2 ] ||
+       any (intersect poly2) verts1 ||
+       any (intersect poly1) verts2
+
+instance (Eq (p a), Floating a, Num (p a), Ord a, Point p) =>
+         Intersect (Circle p a) (Polygon p a) where
+  intersect = flip intersect
+
+instance (Rotation p) => Rotation (Polygon p) where
+  rotate r (Polygon m vs) = Polygon (rotate r m) (map (rotate r) vs)
+  angle (Polygon m _) = angle m
+
+-- | Calculate the convex hull of an arbitrary number of points.
+convexHull' :: forall p a.
+               (Num (p a), Fractional a, Ord a, Scale p, Point p) =>
+               [p a] -> Maybe (Polygon p a)
+convexHull' [] = Nothing
+convexHull' [_] = Nothing
+convexHull' [_,_] = Nothing
+convexHull' ps = Just $
+    Polygon middle (map (subtract middle) hull)
+    where middle :: p a
+          middle = (1 / (fromIntegral.length) hull) `scale`
+                   sum hull
+          hull :: [p a]
+          hull = chain sortedPs
+          chain :: [p a] -> [p a]
+          chain xs = lower ++ upper
+              where lower = go [] xs
+                    upper = go [] (reverse xs)
+          go :: [p a] -> [p a] -> [p a]
+          go acc@(r1:r2:rs) (x:xs)
+              | clockwise r2 r1 x = go (r2:rs) (x:xs)
+              | otherwise = go (x:acc) xs
+          go acc (x:xs) = go (x:acc) xs
+          go acc [] = reverse $ tail acc
+          sortedPs :: [p a]
+          sortedPs = sortBy
+                     (\p q ->
+                         case compare (x p) (x q) of
+                           EQ -> compare (y p) (y q)
+                           c -> c
+                     ) ps
+          clockwise :: p a -> p a -> p a -> Bool
+          clockwise o a b = (a - o) `cross` (b - o) <= 0
+
+rectangleInt :: forall p a. (Point p, RealFloat a, Eq a, Translate p
+                            , Rotation p) =>
+             p a
+          -> a -- ^ length of one side
+          -> a -- ^ length of the other side
+          -> Maybe (Polygon p a)
+rectangleInt m a b
+  | a == 0 || b == 0 = Nothing
+  | otherwise =
+      Just $
+        Polygon
+        m
+        ( sortBy
+          (compare `on` angle)
+          [ fromCoords (negate a/2) (negate b/2) :: p a
+          , fromCoords (a/2) (negate b/2) :: p a
+          , fromCoords (a/2) (b/2) :: p a
+          , fromCoords (negate a/2) (b/2) :: p a
+          ]
+        )
+
+-- | `Shape` describes geometric shapes in the euklidean plain.
+data Shape p a = ShapeCircle (Circle p a)
+               | ShapePolygon (Polygon p a)
+               deriving (Show,Read,Eq)
+
+instance ( Ord a, Distance p p, Eq (p a)
+         , Num (p a), Point p, RealFloat a) =>
+         Intersect (Shape p a) (Shape p a) where
+  intersect (ShapeCircle c) (ShapePolygon p) = c `intersect` p
+  intersect (ShapePolygon p) (ShapeCircle c) = c `intersect` p
+  intersect (ShapeCircle a) (ShapeCircle b) = a `intersect` b
+  intersect (ShapePolygon a) (ShapePolygon b) = a `intersect` b
+
+instance ( Floating a, Eq (p a), Num (p a), Ord a, Point p, Distance p p ) =>
+         Intersect (Shape p a) (p a) where
+  intersect (ShapeCircle c) p = c `intersect` p
+  intersect (ShapePolygon c) p = c `intersect` p
+
+instance ( Floating a, Eq (p a), Num (p a), Ord a, Point p, Distance p p ) =>
+         Intersect (p a) (Shape p a) where
+  intersect = flip intersect
+
+instance (Rotation p, Point p) => Rotation (Shape p) where
+  rotate a (ShapeCircle s) = ShapeCircle (rotate a s)
+  rotate a (ShapePolygon s) = ShapePolygon (rotate a s)
+  angle (ShapeCircle s) = angle s
+  angle (ShapePolygon s) = angle s
diff --git a/Geom2d/Translate.hs b/Geom2d/Translate.hs
new file mode 100644
--- /dev/null
+++ b/Geom2d/Translate.hs
@@ -0,0 +1,12 @@
+module Geom2d.Translate
+
+where
+
+import Geom2d.Point
+import Geom2d.Point.Internal
+  
+class Translate t where
+  translate :: (Point p, Num a) => p a -> t a -> t a
+
+instance Translate Point' where
+  translate p (Point' (a,b)) = Point' (x p + a, y p + b)
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+              GNU GENERAL PUBLIC LICENSE
+                Version 3, 29 June 2007
+
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+
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+
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+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
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diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/Test/Distance.hs b/Test/Distance.hs
new file mode 100644
--- /dev/null
+++ b/Test/Distance.hs
@@ -0,0 +1,21 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+import Data.AEq
+import Geom2d.Point
+import Geom2d.Distance
+import Test.QuickCheck
+import Test.Utils
+
+prop_distance_point_point :: Point' Float -> Point' Float -> Bool
+prop_distance_point_point p q =
+  distance p q ~==
+  sqrt ( (x p - x q)^(2::Int) + (y p - y q)^(2::Int) )
+
+return []
+runTests = $quickCheckAll
+
+main :: IO ()
+main = do
+  putStrLn "Test Distance"
+  runTests >>= doExit
+
diff --git a/Test/Intersect.hs b/Test/Intersect.hs
new file mode 100644
--- /dev/null
+++ b/Test/Intersect.hs
@@ -0,0 +1,49 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+import Geom2d.Intersect
+import Geom2d.Point
+import Geom2d.Line
+import Test.QuickCheck.All
+import Test.QuickCheck
+import Test.Utils
+import Data.AEq
+
+prop_intersect_point_point :: Point' Float -> Point' Float -> Bool
+prop_intersect_point_point a b =
+  (a == b) == (a `intersect` b)
+
+prop_intersect_infline_infline_xaxis :: Float -> Float -> Bool
+prop_intersect_infline_infline_xaxis a b = maybe True id $ do
+  l <- mkInfLine
+       (fromCoords a 0)
+       (fromCoords a b) :: Maybe (InfLine Point' Float)
+  xAxis <- mkInfLine
+           (fromCoords 0 0)
+           (fromCoords 1 0) :: Maybe (InfLine Point' Float)
+  return (l `intersect` xAxis)
+  
+prop_intersect_infline_infline_yaxis :: Float -> Float -> Bool
+prop_intersect_infline_infline_yaxis a b = maybe True id $ do
+  l <- mkInfLine
+       (fromCoords 0 a)
+       (fromCoords b a) :: Maybe (InfLine Point' Float)
+  yAxis <- mkInfLine
+           (fromCoords 0 0)
+           (fromCoords 0 1) :: Maybe (InfLine Point' Float)
+  return (l `intersect` yAxis)
+
+prop_intersect_infline_point :: InfLine Point' Float -> Point' Float -> Bool
+prop_intersect_infline_point line p =
+  (line `intersect` p) `implies`
+  ( maybe True id $ do
+      f <- lineF line
+      return (y p ~== f (x p)))
+  where True `implies` False = False
+        _ `implies` _ = True
+  
+return []
+runTests = $quickCheckAll
+
+main = do
+  putStrLn "Test Intersect.hs"
+  runTests >>= doExit
diff --git a/Test/Line.hs b/Test/Line.hs
new file mode 100644
--- /dev/null
+++ b/Test/Line.hs
@@ -0,0 +1,168 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+import Geom2d.Line
+import Geom2d.Point
+import Geom2d.Translate
+import Geom2d.Distance
+import Geom2d.Intersect
+import Test.QuickCheck.All
+import Test.QuickCheck
+import Data.AEq
+import Data.Maybe
+import Test.Utils
+
+prop_infline_translate :: InfLine Point' Float
+                       -> InfLine Point' Float
+                       -> Point' Float
+                       -> Bool
+prop_infline_translate l1 l2 v =
+  parallel l1 l2 == parallel l1 (translate v l2)
+
+prop_line_function_vertical :: Float -> Bool
+prop_line_function_vertical xarg =
+  maybe False (not.isJust.lineF) $
+    mkInfLine (fromCoords xarg 0 :: Point' Float) (fromCoords xarg 1)
+
+prop_line_function_linear :: Float -> Bool
+prop_line_function_linear xarg = maybe False (\f -> f xarg ~== xarg) $ do
+  line <- mkInfLine (fromCoords 0 0) (fromCoords 1 1 :: Point' Float)
+  lineF line
+
+prop_parallel :: Float -> Bool
+prop_parallel n = maybe True id $ do
+  yAxis <- mkInfLine (fromCoords 0 0 :: Point' Float) (fromCoords 0 1)
+  line <- mkInfLine (fromCoords 1 0) (fromCoords 1 n)
+  return (parallel yAxis line)
+
+prop_slope :: Float -> Float -> Bool
+prop_slope ax ay = maybe True id $ do
+  l <- mkInfLine
+       (fromCoords 0 0 :: Point' Float)
+       (fromCoords ax ay)
+  s <- slope l
+  return $ s == ay / ax
+
+prop_root :: InfLine Point' Float -> Bool
+prop_root l
+  | slope l == Just 0 = isNothing (root l)
+  | isNothing (slope l) = True
+  | otherwise = maybe False id $ do
+      x0 <- root l
+      f <- lineF l
+      return (f x0 ~== 0)
+
+prop_line_equal :: Bool
+prop_line_equal = maybe False (\l -> l == l) $
+  mkInfLine (fromCoords 0 0 :: Point' Float) (fromCoords 1 0)
+
+prop_intersection_equal :: Bool
+prop_intersection_equal = maybe False id $ do
+  xAxis <- mkInfLine (fromCoords 0 0 :: Point' Float) (fromCoords 1 0)
+  return $ (not.isJust) (xAxis `intersection` xAxis)
+
+prop_intersection_parallel :: Bool
+prop_intersection_parallel = maybe False id $ do
+  xAxis <- mkInfLine (fromCoords 0 0 :: Point' Float) (fromCoords 1 0)
+  let line = translate (fromCoords 0 1 :: Point' Float) xAxis
+  return $ (not.isJust) (xAxis `intersection` line)
+
+prop_intersection_origin :: Bool
+prop_intersection_origin = maybe False id $ do
+  xAxis <- mkLine (fromCoords 0 0) (fromCoords 1 0)
+  yAxis <- mkLine (fromCoords 0 0) (fromCoords 0 1)
+  (~== origin) <$> (xAxis `intersection` yAxis)
+  where mkLine :: Point' Float -> Point' Float -> Maybe (InfLine Point' Float)
+        mkLine = mkInfLine
+        origin = fromCoords 0 0
+
+prop_intersection_onYAxis :: Float -> Float -> Bool
+prop_intersection_onYAxis m1 m2 = maybe (m1 == m2) (== fromCoords 0 0) $ do
+  l1 <- mkInfLine (fromCoords 0 0 :: Point' Float) (fromCoords 1 m1)
+  l2 <- mkInfLine (fromCoords 0 0) (fromCoords 1 m2)
+  intersection l1 l2
+
+prop_intersection_yaxis :: Bool
+prop_intersection_yaxis = fromMaybe False $ do
+  l1 <- mkInfLine (fromCoords 0 0 :: Point' Float) (fromCoords 0 1)
+  l2 <- mkInfLine (fromCoords 0 0 :: Point' Float) (fromCoords 1 0)
+  (~== fromCoords 0 0) <$> intersection l1 l2
+
+prop_finline_translate_constant_length :: FinLine Point' Float
+                                       -> Point' Float
+                                       -> Bool
+prop_finline_translate_constant_length l v =
+  lineLength l ~==
+  lineLength (translate v l)
+
+prop_finline_translate_notequal :: FinLine Point' Float
+                                -> Point' Float
+                                -> Bool
+prop_finline_translate_notequal l v
+  | not (magnitude v ~== 0) =
+      not (l ~== (translate v l))
+  | otherwise = (l ~== (translate v l))
+
+prop_finline_distance_1 :: Bool
+prop_finline_distance_1 = maybe False id $ do
+  line <- mkFinLine (fromCoords 0 0 :: Point' Float)
+                    (fromCoords 1 0)
+  return (distance (fromCoords 1 1 :: Point' Float) line ~==
+          1)
+
+prop_finline_distance_2 :: Bool
+prop_finline_distance_2 = maybe False id $ do
+  line <- mkFinLine (fromCoords 0 0 :: Point' Float)
+                    (fromCoords 1 0)
+  return (distance (fromCoords 2 0 :: Point' Float) line ~==
+          1)
+
+prop_finline_distance_3 :: Bool
+prop_finline_distance_3 = maybe False id $ do
+  line <- mkFinLine (fromCoords (-10) 0 :: Point' Float)
+                    (fromCoords 10 0)
+  return (distance (fromCoords 0 1 :: Point' Float) line ~==
+          1)
+
+prop_finline_distance_4 :: Bool
+prop_finline_distance_4 = maybe False id $ do
+  line <- mkFinLine (fromCoords (-10) 0 :: Point' Float)
+                    (fromCoords 10 0)
+  return (distance (fromCoords 0 0 :: Point' Float) line ~==
+          0)
+
+prop_intersect_infline_infline_1 :: Bool
+prop_intersect_infline_infline_1 =
+  maybe False
+  ( \(l1,l2) -> l1 `intersect` l2 )
+  ( (,) <$>
+    mkInfLine (fromCoords (-1) 0 :: Point' Float)
+              (fromCoords 1 0) <*>
+    mkInfLine (fromCoords 0 (-1) :: Point' Float)
+              (fromCoords 0 1))
+
+prop_intersect_finline_finline_1 :: Bool
+prop_intersect_finline_finline_1 =
+  maybe False
+  ( \(l1,l2) -> l1 `intersect` l2 )
+  ( (,) <$>
+    mkFinLine (fromCoords (-1) 0 :: Point' Float)
+              (fromCoords 1 0) <*>
+    mkFinLine (fromCoords 0 (-1) :: Point' Float)
+              (fromCoords 0 1))
+
+prop_intersect_infline_finline_1 :: Bool
+prop_intersect_infline_finline_1 =
+  maybe False
+  ( \(l1,l2) -> l1 `intersect` l2 )
+  ( (,) <$>
+    mkInfLine (fromCoords (-1) 0 :: Point' Float)
+              (fromCoords 1 0) <*>
+    mkFinLine (fromCoords 0 (-1) :: Point' Float)
+              (fromCoords 0 1))
+
+return []
+runTests = $quickCheckAll
+
+main = do
+  putStrLn "Line.hs"
+  runTests >>= doExit
diff --git a/Test/Point.hs b/Test/Point.hs
new file mode 100644
--- /dev/null
+++ b/Test/Point.hs
@@ -0,0 +1,141 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+import Data.AEq
+import Data.Maybe
+import Geom2d.Point
+import Geom2d.Rotation
+import Test.QuickCheck
+import Test.QuickCheck.All
+import Test.Utils
+import Data.Fixed
+
+mkpropPoint :: forall a p. (Arbitrary (p a), Point p, Eq a) =>
+                 p a -> Bool
+mkpropPoint p =
+  and [ prop_identity
+      ]
+  where prop_identity = x p == x idPoint &&
+                        y p == y idPoint
+        idPoint :: p a
+        idPoint = fromCoords (x p) (y p)
+
+mkpropNum :: (Arbitrary a, Num a) => (a -> a -> Bool) -> a -> Bool
+mkpropNum isEqual x =
+    x `isEqual` (signum x * abs x)
+
+mkpropFunctor :: (Arbitrary (f a), Eq (f a), Functor f) =>
+                  f a -> Bool
+mkpropFunctor x =
+  fmap id x == x
+
+mkpropScale :: (Arbitrary (p a), Scale p, Floating a, Point p) =>
+                (a -> a -> Bool) -> p a -> a -> Bool
+mkpropScale comparison p a =
+  (magnitude p * abs a) `comparison`
+  magnitude (a `scale` p)
+
+mkpropNormalize :: (Arbitrary (p a), Point p, Scale p, Floating a, AEq a
+                    , Num a) =>
+                p a -> Bool
+mkpropNormalize v =
+  maybe (magnitude v ~== 0)
+  ( (~== 1).magnitude )
+  ( normalize v)
+
+prop_point_point' :: Point' Integer -> Bool
+prop_point_point' = mkpropPoint
+
+prop_num_point' :: Point' Float -> Bool
+prop_num_point' = mkpropNum (~==)
+
+prop_functor_point' :: Point' Integer -> Bool
+prop_functor_point' = mkpropFunctor
+
+prop_point'_magnitude :: Point' Float -> Bool
+prop_point'_magnitude p =
+  sqrt ( x p ^ 2 + y p ^ 2 ) ~== magnitude p
+
+prop_triarea :: Float -> Float -> Bool
+prop_triarea a b =
+  triArea triangle ~== abs ((a * b) / 2)
+  where triangle :: Triangle (Point' Float)
+        triangle = ( fromCoords 0 0
+                   , fromCoords a 0
+                   , fromCoords 0 b
+                   )
+
+prop_point_scale :: Point' Float -> Float -> Bool
+prop_point_scale = mkpropScale (~==)
+
+prop_point_normalize :: Point' Float -> Bool
+prop_point_normalize = mkpropNormalize
+
+prop_pointInTriangle :: Bool
+prop_pointInTriangle =
+  pointInTriangle tri p
+  where tri = ( fromCoords (-1) (-1)
+              , fromCoords 1 (-1)
+              , fromCoords 0 1
+              )
+        p :: Point' Float
+        p = fromCoords 0 0
+
+prop_pointInTriangle_onVert :: Bool
+prop_pointInTriangle_onVert =
+  pointInTriangle tri p
+  where p = fromCoords 0 0
+        tri :: Triangle (Point' Float)
+        tri = (p, fromCoords 1 1, fromCoords 1 (-1))
+
+prop_angle_zero :: Bool
+prop_angle_zero =
+  angle (fromCoords 1 0 :: Point' Float) == Just 0
+
+prop_point_show_read :: Point' Float -> Bool
+prop_point_show_read p =
+  p == (read.show) p
+
+prop_point_add :: Point' Float -> Point' Float -> Bool
+prop_point_add p q =
+  x (p + q) == x p + x q &&
+  y (p + q) == y p + y q
+
+prop_point_negate :: Point' Float -> Bool
+prop_point_negate p =
+  x (negate p) == negate (x p) &&
+  y (negate p) == negate (y p)
+
+prop_triangle_invalid :: Bool
+prop_triangle_invalid =
+  let tri :: Triangle (Point' Float)
+      tri = ( fromCoords 0 0
+            , fromCoords 1 1
+            , fromCoords 1 1
+            )
+  in not (pointInTriangle tri (fromCoords 0 0))
+
+prop_rotation_point_linear :: Point' Float -> Bool
+prop_rotation_point_linear x =
+  fromMaybe True
+  ( (~==) <$>
+    angle (r `rotate` x) <*>
+    ((subtract pi).((`mod'` (2*pi)).(+pi).(+r)) <$> angle x)
+  )
+  where r = 1.2
+
+prop_rotation_point_bounds :: Point' Float -> Bool
+prop_rotation_point_bounds x =
+  fromMaybe True
+  ( fmap
+    (\a -> a >= (- pi) && a <= pi)
+    (angle x)
+  )
+
+return []
+runTests = $quickCheckAll
+
+main :: IO ()
+main = do
+  putStrLn "Test Point"
+  runTests >>= doExit
diff --git a/Test/Shape.hs b/Test/Shape.hs
new file mode 100644
--- /dev/null
+++ b/Test/Shape.hs
@@ -0,0 +1,168 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+import Data.AEq
+import Data.Fixed
+import Data.Maybe
+import Geom2d.Distance
+import Geom2d.Intersect
+import Geom2d.Point
+import Geom2d.Rotation
+import Geom2d.Shape
+import Geom2d.Shape.Internal
+import Test.QuickCheck
+import Test.Utils
+
+prop_circle_radius :: Point' Float -> Float -> Bool
+prop_circle_radius m r =
+  radius (mkCircleInt m r) ~== abs r
+
+prop_circle_rotate_1 :: Bool
+prop_circle_rotate_1 =
+  rotate 5 circ == circ
+  where circ :: Shape Point' Float
+        circ = circle (fromCoords 0 0) 4
+
+prop_circle_rotate_2 :: Point' Float -> Bool
+prop_circle_rotate_2 m =
+  let circ = circle m 1
+  in angle circ ~== angle m
+
+prop_circle_center :: Point' Float -> Float -> Bool
+prop_circle_center m r =
+  center (mkCircleInt m r) ~== m
+
+prop_distance_circle_point :: Bool
+prop_distance_circle_point =
+  distance
+  (mkCircleInt (fromCoords 0 0 :: Point' Float) 1)
+  (fromCoords 5 0 :: Point' Float) ~== 4
+
+prop_point_in_circle :: Bool
+prop_point_in_circle =
+  let circ :: Circle Point' Float
+      circ = mkCircleInt (fromCoords 0 0) 1
+      p :: Point' Float
+      p = fromCoords 0 0
+  in circ `intersect` p &&
+     p `intersect` circ
+
+prop_intersect_circle_circle :: Circle Point' Float
+                             -> Circle Point' Float
+                             -> Bool
+prop_intersect_circle_circle a b =
+  intersect a b ==
+  ( distance (center a) (center b) <= radius a + radius b )
+
+prop_point_outside_circle :: Bool
+prop_point_outside_circle =
+  let circ :: Shape Point' Float
+      circ = circle (fromCoords 0 0) 1
+      p :: Point' Float
+      p = fromCoords 2 0
+  in not (circ `intersect` p) ||
+     not (p `intersect` circ)
+
+prop_point_in_polygon :: Bool
+prop_point_in_polygon =
+  maybe
+  False
+  ( intersect (fromCoords 0 0::Point' Float) )
+  ( rectangle (fromCoords 0 0::Point' Float) 1 1 )
+
+prop_point_outside_polygon :: Bool
+prop_point_outside_polygon =
+  maybe
+  False
+  ( not.intersect (fromCoords 10 0::Point' Float) )
+  ( rectangle (fromCoords 0 0::Point' Float) 1 1 )
+
+prop_point_outside_polygon_1 :: Bool
+prop_point_outside_polygon_1 =
+  maybe
+  False
+  ( not.intersect (fromCoords (-5) 0 :: Point' Float))
+  ( rectangle (fromCoords 0 5 :: Point' Float) 4 4)
+
+prop_intersect_polygon_circle_1 :: Bool
+prop_intersect_polygon_circle_1 =
+  maybe False
+  ( intersect (circle (fromCoords 0 0 :: Point' Float) 1 ))
+  ( rectangle (fromCoords 0 0 :: Point' Float) 4 4 )
+
+prop_intersect_polygon_circle_2 :: Bool
+prop_intersect_polygon_circle_2 =
+  maybe False
+  ( (intersect :: Shape Point' Float -> Shape Point' Float -> Bool)
+    (circle (fromCoords 0 5 :: Point' Float) 4 ))
+  ( rectangle (fromCoords 0 0 :: Point' Float) 4 4 )
+
+-- | This test make a rectangleInt (-9,-9) (11,11) and a circle (10,15)
+-- with radius 2.  so these shapes should not intersect.
+prop_intersect_polygon_circle_3 :: Bool
+prop_intersect_polygon_circle_3 =
+  maybe False
+  ( not.
+    (intersect :: Shape Point' Float -> Shape Point' Float -> Bool)
+    (circle (fromCoords 10 15 :: Point' Float) 2 ))
+  ( rectangle (fromCoords 10 10 :: Point' Float) 1 1 )
+
+prop_intersect_polygon_1 :: Bool
+prop_intersect_polygon_1 =
+  fromMaybe False $
+    intersect <$>
+    rectangle (fromCoords 0 0 :: Point' Float) 1 3 <*>
+    rectangle (fromCoords 1 2 :: Point' Float) 3 1
+
+prop_intersect_polygon_eq :: Polygon Point' Float -> Bool
+prop_intersect_polygon_eq p = p `intersect` p
+
+prop_polygon_convexHull_1 :: Bool
+prop_polygon_convexHull_1 =
+  fromMaybe False $ do
+    shape <- convexHull' [ fromCoords (-1) (-1) :: Point' Float
+                         , fromCoords 1 (-1)
+                         , fromCoords 1 1
+                         , fromCoords (-1) 1
+                         ]
+    return ( shape `intersect` point 1 1 &&
+             shape `intersect` point (-1) 1 &&
+             shape `intersect` point 1 (-1) &&
+             shape `intersect` point (-1) (-1))
+  where point :: Float -> Float -> Point' Float
+        point = fromCoords
+
+prop_polygon_convexHull_2 :: Bool
+prop_polygon_convexHull_2 =
+  fromMaybe False $ do
+    shape <- convexHull' points
+    return (all (intersect shape) points)
+  where points = [ point 5 5
+                 , point 7 4
+                 , point 8 3
+                 , point 10 20
+                 , point 2 20
+                 , point 5 5
+                 ]
+        point :: Float -> Float -> Point' Float
+        point = fromCoords
+
+prop_polygon_rotate :: Polygon Point' Float -> Bool
+prop_polygon_rotate p =
+  fromMaybe True $ do
+    angBefore <- angle p
+    angAfter <- angle (rotate rotAng p)
+    return (normalize (angBefore + rotAng) ~== angAfter)
+  where rotAng = 1
+        normalize = subtract pi.(`mod'` (2*pi)).(+pi)
+
+prop_polygon_rotate_defined :: Bool
+prop_polygon_rotate_defined =
+  fromMaybe False $ do
+    rect <- rectangle (fromCoords 1 0 :: Point' Float) 1 1
+    ang <- angle rect
+    return (ang ~== 0)
+
+return []
+runTests = $quickCheckAll
+
+main = runTests >>= doExit
diff --git a/Test/Translate.hs b/Test/Translate.hs
new file mode 100644
--- /dev/null
+++ b/Test/Translate.hs
@@ -0,0 +1,21 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+import Geom2d.Translate
+import Geom2d.Point
+import Test.Utils
+import Test.QuickCheck.All
+import Test.QuickCheck
+import Data.AEq
+
+prop_point_translate_identity :: Point' Float -> Bool
+prop_point_translate_identity p =
+  translate (fromCoords 0 0 :: Point' Float) p == p
+
+prop_point_translate_addition :: Point' Float -> Point' Float -> Bool
+prop_point_translate_addition p q = p `translate` q ~== p + q
+
+return []
+runTests = $quickCheckAll
+
+main = do
+  runTests >>= doExit
diff --git a/Test/Utils.hs b/Test/Utils.hs
new file mode 100644
--- /dev/null
+++ b/Test/Utils.hs
@@ -0,0 +1,9 @@
+module Test.Utils
+
+where
+
+import System.Exit
+
+doExit :: Bool -> IO ()
+doExit True = exitSuccess
+doExit False = exitFailure
diff --git a/geom2d.cabal b/geom2d.cabal
new file mode 100644
--- /dev/null
+++ b/geom2d.cabal
@@ -0,0 +1,72 @@
+name:                geom2d
+version:             0.1.0.1
+synopsis:            package for geometry in euklidean 2d space
+description:         This package provides tools for dealing with geometric
+                     objects in 2D space.
+license:             GPL-3
+license-file:        LICENSE
+author:              Sebastian Jordan
+maintainer:          sebastian.jordan.mail@googlemail.com
+category:            Math
+build-type:          Simple
+cabal-version:       >=1.10
+extra-source-files:  Test/Utils.hs
+
+source-repository head
+  type:      darcs
+  location:  http://hub.darcs.net/seppeljordan/geom2d/
+
+library
+  exposed-modules:     Geom2d.Intersect, Geom2d.Point, Geom2d.Distance
+                     , Geom2d.Line, Geom2d.Point.Internal
+                     , Geom2d.Line.Internal, Geom2d.Shape
+                     , Geom2d.Translate, Geom2d.Shape.Internal
+                     , Geom2d.Rotation, Geom2d
+  other-extensions:    MultiParamTypeClasses, FlexibleContexts, TemplateHaskell
+                     , ScopedTypeVariables
+  build-depends:       base >=4.8 && <4.9, QuickCheck >=2.7 && <2.8
+                     , ieee754 >=0.7 && <0.8
+  default-language:    Haskell2010
+  ghc-options:         -Wall
+
+Test-Suite point
+  default-language:    Haskell2010
+  type:                exitcode-stdio-1.0
+  main-is:             Test/Point.hs
+  build-depends:       base >= 4.8 && < 4.9, ieee754 >= 0.7 && < 0.8
+                     , QuickCheck >= 2.7 && < 2.8
+
+Test-Suite line
+  default-language:    Haskell2010
+  type:                exitcode-stdio-1.0
+  main-is:             Test/Line.hs
+  build-depends:       base >= 4.8 && < 4.9, ieee754 >= 0.7 && < 0.8
+                     , QuickCheck >= 2.7 && < 2.8
+
+Test-Suite intersect
+  default-language:    Haskell2010
+  type:                exitcode-stdio-1.0
+  main-is:             Test/Intersect.hs
+  build-depends:       base >= 4.8 && < 4.9, ieee754 >= 0.7 && < 0.8
+                     , QuickCheck >= 2.7 && < 2.8
+
+Test-Suite distance
+  default-language:    Haskell2010
+  type:                exitcode-stdio-1.0
+  main-is:             Test/Distance.hs
+  build-depends:       base >= 4.8 && < 4.9, ieee754 >= 0.7 && < 0.8
+                     , QuickCheck >= 2.7 && < 2.8
+
+Test-Suite translate
+  default-language:    Haskell2010
+  type:                exitcode-stdio-1.0
+  main-is:             Test/Translate.hs
+  build-depends:       base >= 4.8 && < 4.9, ieee754 >= 0.7 && < 0.8
+                     , QuickCheck >= 2.7 && < 2.8
+
+Test-Suite shape
+  default-language:    Haskell2010
+  type:                exitcode-stdio-1.0
+  main-is:             Test/Shape.hs
+  build-depends:       base >= 4.8 && < 4.9, ieee754 >= 0.7 && < 0.8
+                     , QuickCheck >= 2.7 && < 2.8