src/Face.hs: don't import "Point" type members.

[spline3.git] / src / Face.hs

diff --git a/src/Face.hs b/src/Face.hs
index d93ebffba1457f873d7296f9f29cfd534dfcc749..de24a43e6c1cd72afb2c88b79507a38c7a48640e 100644 (file)
--- a/src/Face.hs
+++ b/src/Face.hs
@@ -1,160 +1,31 @@
-module Face
+-- | The Face module just contains the definition of the 'Face' data
+--   type and its two typeclass instances.
+--
+module Face (
+  Face(..),
+  center )
 where
 
-import Cube
-import Grid
-import Point
-import Tetrahedron hiding (c, cube, v0, v1, v2, v3)
-import ThreeDimensional
+import Point ( Point, scale )
 
-data Face = Face { cube :: Cube,
-                   v0 :: Point,
-                   v1 :: Point,
-                   v2 :: Point,
-                   v3 :: Point }
+data Face = Face { v0 :: !Point,
+                   v1 :: !Point,
+                   v2 :: !Point,
+                   v3 :: !Point }
           deriving (Eq)
 
 instance Show Face where
-    show f = "Face (Cube_" ++ (show i') ++ "," ++ (show j') ++ "," ++
-             (show k') ++ ") " ++ "(v0: " ++ (show (v0 f)) ++ ") (v1: " ++
-             (show (v1 f)) ++ ") (v2: " ++ (show (v2 f)) ++ ") (v3: " ++
-             (show (v3 f)) ++ ")\n\n"
-             where
-               i' = i (cube f)
-               j' = j (cube f)
-               k' = k (cube f)
-
-instance ThreeDimensional Face where
-    center f = ((v0 f) + (v1 f) + (v2 f) + (v3 f)) `scale` (1/4)
-    -- Too lazy to implement this right now.
-    contains_point _ _ = False
-
--- The top face of the cube.
-face0 :: Cube -> Face
-face0 c = Face c v0' v1' v2' v3'
-    where
-      g = grid c
-      delta = (1/2)*(h g)
-      v0' = (center c) + (-delta, delta, delta)
-      v1' = (center c) + (delta, delta, delta)
-      v2' = (center c) + (delta, -delta, delta)
-      v3' = (center c) + (-delta, -delta, delta)
-
--- The right face of the cube.
-face1 :: Cube -> Face
-face1 c = Face c v0' v1' v2' v3'
-    where
-      g = grid c
-      delta = (1/2)*(h g)
-      v0' = (center c) + (delta, delta, delta)
-      v1' = (center c) + (delta, delta, -delta)
-      v2' = (center c) + (delta, -delta, -delta)
-      v3' = (center c) + (delta, -delta, delta)
-
-
--- The bottom face of the cube.
-face2 :: Cube -> Face
-face2 c = Face c v0' v1' v2' v3'
-    where
-      g = grid c
-      delta = (1/2)*(h g)
-      v0' = (center c) + (delta, delta, -delta)
-      v1' = (center c) + (-delta, delta, -delta)
-      v2' = (center c) + (-delta, -delta, -delta)
-      v3' = (center c) + (delta, -delta, -delta)
-
-
--- The left face of the cube.
-face3 :: Cube -> Face
-face3 c = Face c v0' v1' v2' v3'
-    where
-      g = grid c
-      delta = (1/2)*(h g)
-      v0' = (center c) + (-delta, delta, -delta)
-      v1' = (center c) + (-delta, delta, delta)
-      v2' = (center c) + (-delta, -delta, delta)
-      v3' = (center c) + (-delta, -delta, -delta)
-
-
--- The front face of the cube.
-face4 :: Cube -> Face
-face4 c = Face c v0' v1' v2' v3'
-    where
-      g = grid c
-      delta = (1/2)*(h g)
-      v0' = (center c) + (-delta, -delta, delta)
-      v1' = (center c) + (delta, -delta, delta)
-      v2' = (center c) + (delta, -delta, -delta)
-      v3' = (center c) + (-delta, -delta, -delta)
-
-
--- The back face of the cube.
-face5 :: Cube -> Face
-face5 c = Face c v0' v1' v2' v3'
-    where
-      g = grid c
-      delta = (1/2)*(h g)
-      v0' = (center c) + (-delta, delta, -delta)
-      v1' = (center c) + (delta, delta, -delta)
-      v2' = (center c) + (delta, delta, delta)
-      v3' = (center c) + (-delta, delta, delta)
-
-
-tetrahedron0 :: Face -> Tetrahedron
-tetrahedron0 f =
-    Tetrahedron c v0' v1' v2' v3'
-    where
-      c = cube f
-      v0' = v0 f
-      v1' = v1 f
-      v2' = center f
-      v3' = center c
-
-tetrahedron1 :: Face -> Tetrahedron
-tetrahedron1 f =
-    Tetrahedron c v0' v1' v2' v3'
-    where
-      c = cube f
-      v0' = v1 f
-      v1' = v2 f
-      v2' = center f
-      v3' = center c
-
-
-tetrahedron2 :: Face -> Tetrahedron
-tetrahedron2 f =
-    Tetrahedron c v0' v1' v2' v3'
-    where
-      c = cube f
-      v0' = v2 f
-      v1' = v3 f
-      v2' = center f
-      v3' = center c
-
-
-tetrahedron3 :: Face -> Tetrahedron
-tetrahedron3 f =
-    Tetrahedron c v0' v1' v2' v3'
-    where
-      c = cube f
-      v0' = v3 f
-      v1' = v0 f
-      v2' = center f
-      v3' = center c
-
-tetrahedrons :: Cube -> [Tetrahedron]
-tetrahedrons c =
-    concat [
- [tetrahedron0 f0, tetrahedron1 f0, tetrahedron2 f0, tetrahedron3 f0],
- [tetrahedron0 f1, tetrahedron1 f1, tetrahedron2 f1, tetrahedron3 f2],
- [tetrahedron0 f2, tetrahedron1 f2, tetrahedron2 f2, tetrahedron3 f2],
- [tetrahedron0 f3, tetrahedron1 f3, tetrahedron2 f3, tetrahedron3 f3],
- [tetrahedron0 f4, tetrahedron1 f4, tetrahedron2 f4, tetrahedron3 f4],
- [tetrahedron0 f5, tetrahedron1 f5, tetrahedron2 f5, tetrahedron3 f5] ]
-    where
-      f0 = face0 c
-      f1 = face1 c
-      f2 = face2 c
-      f3 = face3 c
-      f4 = face4 c
-      f5 = face5 c
+    show (Face v0' v1' v2' v3') =
+      "Face:\n" ++
+        "  v0: " ++ (show v0') ++ "\n" ++
+        "  v1: " ++ (show v1') ++ "\n" ++
+        "  v2: " ++ (show v2') ++ "\n" ++
+        "  v3: " ++ (show v3') ++ "\n"
+
+-- | Returns the center of the given face. Since a face is just
+--   square, we can average the four vertices to find its center. This
+--   is useful because the center of a face is always a vertex of a
+--   tetrahedron.
+center :: Face -> Point
+center (Face v0' v1' v2' v3') =
+  (v0' + v1' + v2' + v3') `scale` (1/4)