Fix all orphan instances.

[spline3.git] / src / Cube.hs

diff --git a/src/Cube.hs b/src/Cube.hs
index 2ec9e4848318fb12135309900e5505df20f3614e..6941425a82be541635168da6d5af85feb1a070b7 100644 (file)
--- a/src/Cube.hs
+++ b/src/Cube.hs
@@ -1,6 +1,8 @@
 module Cube
 where
 
+import Test.QuickCheck (Arbitrary(..), Gen, Positive(..), choose)
+    
 import Cardinal
 import qualified Face (Face(Face, v0, v1, v2, v3))
 import FunctionValues
@@ -16,6 +18,19 @@ data Cube = Cube { h :: Double,
             deriving (Eq)
 
 
+instance Arbitrary Cube where
+    arbitrary = do
+      (Positive h') <- arbitrary :: Gen (Positive Double)
+      i' <- choose (coordmin, coordmax)
+      j' <- choose (coordmin, coordmax)
+      k' <- choose (coordmin, coordmax)
+      fv' <- arbitrary :: Gen FunctionValues
+      return (Cube h' i' j' k' fv')
+        where
+          coordmin = -268435456 -- -(2^29 / 2)
+          coordmax = 268435456  -- +(2^29 / 2)
+
+
 instance Show Cube where
     show c =
         "Cube_" ++ subscript ++ "\n" ++