X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FTetrahedron.hs;h=d468f0c570a920fe3967fdd7e20973ef2cd9945e;hb=aed1b3cc557b67aca7d8b3259f44715078db94ae;hp=eef16566352fdcaedf7d2f0455d65b05a29a8c68;hpb=2da1ed2fd5929baa129812632068540a3c38a253;p=spline3.git

diff --git a/src/Tetrahedron.hs b/src/Tetrahedron.hs
index eef1656..d468f0c 100644
--- a/src/Tetrahedron.hs
+++ b/src/Tetrahedron.hs
@@ -3,7 +3,7 @@ where
 
 import Numeric.LinearAlgebra hiding (i, scale)
 import Prelude hiding (LT)
-import Test.QuickCheck (Arbitrary(..), Gen)
+import Test.QuickCheck (Arbitrary(..), Gen, choose)
 
 import Cardinal
 import Comparisons (nearly_ge)
@@ -13,13 +13,20 @@ import Point
 import RealFunction
 import ThreeDimensional
 
-data Tetrahedron = Tetrahedron { fv :: FunctionValues,
-                                 v0 :: Point,
-                                 v1 :: Point,
-                                 v2 :: Point,
-                                 v3 :: Point,
-                                 precomputed_volume :: Double }
-                   deriving (Eq)
+data Tetrahedron =
+  Tetrahedron { fv :: FunctionValues,
+                v0 :: Point,
+                v1 :: Point,
+                v2 :: Point,
+                v3 :: Point,
+                precomputed_volume :: Double,
+
+                -- | Between 0 and 23; used to quickly determine which
+                --   tetrahedron I am in the parent 'Cube' without
+                --   having to compare them all.
+                number :: Int
+              }
+    deriving (Eq)
 
 
 instance Arbitrary Tetrahedron where
@@ -29,8 +36,13 @@ instance Arbitrary Tetrahedron where
       rnd_v2 <- arbitrary :: Gen Point
       rnd_v3 <- arbitrary :: Gen Point
       rnd_fv <- arbitrary :: Gen FunctionValues
-      rnd_vol <- arbitrary :: Gen Double
-      return (Tetrahedron rnd_fv rnd_v0 rnd_v1 rnd_v2 rnd_v3 rnd_vol)
+      rnd_no <- choose (0,23)
+
+      -- We can't assign an incorrect precomputed volume,
+      -- so we have to calculate the correct one here.
+      let t' = Tetrahedron rnd_fv rnd_v0 rnd_v1 rnd_v2 rnd_v3 0 rnd_no
+      let vol = volume t'
+      return (Tetrahedron rnd_fv rnd_v0 rnd_v1 rnd_v2 rnd_v3 vol rnd_no)
 
 
 instance Show Tetrahedron where
@@ -267,27 +279,27 @@ volume t
 
 -- | The barycentric coordinates of a point with respect to v0.
 b0 :: Tetrahedron -> (RealFunction Point)
-b0 t point = (volume inner_tetrahedron) / (volume t)
+b0 t point = (volume inner_tetrahedron) / (precomputed_volume t)
              where
                inner_tetrahedron = t { v0 = point }
 
 
 -- | The barycentric coordinates of a point with respect to v1.
 b1 :: Tetrahedron -> (RealFunction Point)
-b1 t point = (volume inner_tetrahedron) / (volume t)
+b1 t point = (volume inner_tetrahedron) / (precomputed_volume t)
              where
                inner_tetrahedron = t { v1 = point }
 
 
 -- | The barycentric coordinates of a point with respect to v2.
 b2 :: Tetrahedron -> (RealFunction Point)
-b2 t point = (volume inner_tetrahedron) / (volume t)
+b2 t point = (volume inner_tetrahedron) / (precomputed_volume t)
              where
                inner_tetrahedron = t { v2 = point }
 
 
 -- | The barycentric coordinates of a point with respect to v3.
 b3 :: Tetrahedron -> (RealFunction Point)
-b3 t point = (volume inner_tetrahedron) / (volume t)
+b3 t point = (volume inner_tetrahedron) / (precomputed_volume t)
              where
                inner_tetrahedron = t { v3 = point }