Working cloud shadows (slow)

src/Picture.hs

@@ -27,6 +27,7 @@ module Picture
     , appendPic
     , tranRot
     , translate
+    , translate3
     , rotate
     , scale
     , color
@@ -161,17 +162,21 @@ color :: RGBA -> Picture -> Picture
 {-# INLINE color #-}
 color c = map $ overCol (const c)
 
-translate3 :: Float -> Float -> Point3 -> Point3
-{-# INLINE translate3 #-}
-translate3 !a !b (V3 x y z) = V3 (x+a) (y+b) z
+translateH :: Float -> Float -> Point3 -> Point3
+{-# INLINE translateH #-}
+translateH !a !b (V3 x y z) = V3 (x+a) (y+b) z
 
 translate :: Float -> Float -> Picture -> Picture
 {-# INLINE translate #-}
-translate x = map . overPos . translate3 x
+translate x = map . overPos . translateH x
+
+translate3 :: Point3 -> Picture -> Picture
+{-# INLINE translate3 #-}
+translate3 v = map $ overPos (+.+.+ v)
 
 tranRot :: V2 Float -> Float -> Picture -> Picture
 {-# INLINE tranRot #-}
-tranRot (V2 x y) r = map $ overPos (translate3 x y . rotate3 r)
+tranRot (V2 x y) r = map $ overPos (translateH x y . rotate3 r)
 
 setDepth :: Float -> Picture -> Picture
 {-# INLINE setDepth #-}