Try to fuse functions over pictures (overPos and overCol)

src/Picture.hs

@@ -88,7 +88,7 @@ polygonCol = PolygonCol 0
 
 color :: RGBA -> Picture -> Picture
 {-# INLINE color #-}
-color c pic = Color c pic
+color c pic = OverPic id id (const c) pic
 
 translate3 :: Float -> Float -> Point3 -> Point3
 {-# INLINE translate3 #-}
@@ -96,11 +96,11 @@ translate3 a b (x,y,z) = (x+a,y+b,z)
 
 translate :: Float -> Float -> Picture -> Picture
 {-# INLINE translate #-}
-translate x y pic = Translate x y pic
+translate x y pic = OverPic (translate3 x y) id id pic
 
 setDepth :: Float -> Picture -> Picture
 {-# INLINE setDepth #-}
-setDepth d pic = SetDepth d pic
+setDepth d pic = OverPic (\(x,y,_) -> (x,y,-d)) id id pic
 
 setLayer :: Int -> Picture -> Picture
 setLayer _ Blank = Blank
@@ -115,6 +115,7 @@ setLayer i (Rotate x p) = Rotate x $ setLayer i p
 setLayer i (SetDepth x p) = SetDepth x $ setLayer i p
 setLayer i (Color x p) = Color x $ setLayer i p
 setLayer i (Pictures p) = Pictures $ map (setLayer i) p
+setLayer i (OverPic f f' f'' pic) = OverPic f f' f'' (setLayer i pic)
 
 
 scale3 :: Float -> Float -> Point3 -> Point3
@@ -123,15 +124,16 @@ scale3 a b (x,y,z) = (x*a,y*b,z)
 
 scale :: Float -> Float -> Picture -> Picture
 {-# INLINE scale #-}
-scale x y pic = Scale x y pic
+scale x y pic = OverPic (scale3 x y) ((*) x) id pic
 
 rotate3 :: Float -> Point3 -> Point3
 {-# INLINE rotate3 #-}
 rotate3 a (x,y,z) = (x',y',z)
     where (x',y') = rotateV a (x,y)
 
-rotate = Rotate
+rotate :: Float -> Picture -> Picture
 {-# INLINE rotate #-}
+rotate a pic = OverPic (rotate3 a) id id pic
 
 --rotateRad a = Rotate a
 --{-# INLINE rotateRad #-}