Add possible cosmetic pipes to tanks

src/Dodge/Base/CardinalPoint.hs

@@ -0,0 +1,15 @@
+module Dodge.Base.CardinalPoint where
+import Dodge.Data.Room
+import Geometry
+
+cardList :: [CardinalPoint]
+cardList = [North,East,South,West]
+
+cardVec :: CardinalPoint -> Point2
+cardVec cp = case cp of
+    North -> V2  0   1
+    South -> V2  0 (-1)
+    East -> V2   1   0
+    West -> V2 (-1)  0
+
+