Remove tweakz shader

src/Picture/Base.hs

@@ -8,7 +8,6 @@ module Picture.Base (
     blank,
     polygon,
     polygonWire,
-    polygonZ,
     polygonCol,
     poly3,
     poly3Col,
@@ -73,12 +72,6 @@ polygon = map f . polyToTris
   where
     f (V2 x y) = Verx (V3 x y 0) black [] BottomLayer polyNum
 
-polygonZ :: [Point2] -> Float -> Picture
-{-# INLINE polygonZ #-}
-polygonZ ps z = map (f . zeroZ) $ polyToTris ps
-  where
-    f pos = Verx pos black [z] BottomLayer polyzNum
-
 polygonCol :: [(Point2, RGBA)] -> Picture
 {-# INLINE polygonCol #-}
 polygonCol = polyToTris . map f