Creature shadow test

src/Polyhedra.hs

@@ -34,6 +34,16 @@ constructEdges (face:faces) = mapMaybe (findReverseEdge otherEdges) (faceEdges f
     otherEdges = concatMap faceEdges faces
 constructEdges _ = []
 
+-- | a version of construct edges that directly returns the flattened list of
+-- tuples
+constructEdgesList :: [[Point3]] -> [Point3]
+constructEdgesList (face:faces) = concatMap (findReverseEdgeList otherEdges) (faceEdges face) 
+    ++ constructEdgesList faces
+  where
+    otherEdges = concatMap faceEdges faces
+constructEdgesList _ = []
+
+
 findReverseEdge 
     :: [(Point3,Point3,Point3)] 
     -> (Point3,Point3,Point3) 
@@ -41,6 +51,14 @@ findReverseEdge
 findReverseEdge otherEdges (x,y,z) = (\(_,_,n) -> (x,y,z,n))
     <$> find (\(a,b,_) -> (x,y) == (b,a)) otherEdges
 
+findReverseEdgeList
+    :: [(Point3,Point3,Point3)] 
+    -> (Point3,Point3,Point3) 
+    -> [Point3]
+findReverseEdgeList a b = case findReverseEdge a b of
+    Nothing -> []
+    Just (x,y,z,w) -> [x,y,z,w]
+
 faceEdges :: [Point3] -> [(Point3,Point3,Point3)]
 faceEdges xs = zipWith addNormal xs (tail xs ++ [head xs])
   where