Almost working shadows

src/Geometry/Vector3D.hs

@@ -26,13 +26,13 @@ infixl 7 *.*.*
     !z = z1 - z2
   in (x, y, z)
 {- | 3D scalar multiplication.  -}
-(*.*.*) :: Point3 -> Point3 -> Point3
+(*.*.*) :: Float -> Point3 -> Point3
 {-# INLINE (*.*.*) #-}
-(x1, y1, z1) *.*.* (x2, y2, z2) =
+a *.*.* (x2, y2, z2) =
   let
-    !x = x1 * x2
-    !y = y1 * y2
-    !z = z1 * z2
+    !x = a * x2
+    !y = a * y2
+    !z = a * z2
   in (x, y, z)
 
 crossProd :: Point3 -> Point3 -> Point3
@@ -48,3 +48,11 @@ rotate3 a (x,y,z) = (x',y',z)
   where 
     (x',y') = rotateV a (x,y)
 
+magV3 :: Point3 -> Float
+magV3 (x,y,z) = sqrt $ x^i + y^i + z^i
+  where
+    i = 2 :: Int
+
+normalizeV3 :: Point3 -> Point3
+normalizeV3 (0,0,0) = (0,0,0)
+normalizeV3 p = (1 / magV3 p) *.*.* p