Hack partially working gui line to dropped items

src/Picture.hs

@@ -12,6 +12,7 @@ module Picture
     , thickArc
     , thickCircle
     , thickLine
+    , thickLineCol
     , circleSolid
     , circleSolidCol
     , circle
@@ -260,7 +261,7 @@ thickLineCol ps t = pictures $ f ps
         ,(y +.+ n x y,c')
         ] : f ((y,c'):ys)
     f _             = []
-    n a b = (t*0.5) *.* errorNormalizeV 42 (vNormal (a -.- b))
+    n a b = (t*0.5) *.* safeNormalizeV (vNormal (a -.- b))
 
 thickCircle :: Float -> Float -> Picture
 {-# INLINE thickCircle #-}