Edges when exporting a graphic

Question

I use a graphics primitive:

  square = Graphics[{EdgeForm[], Rectangle[{-1, -1}, {1, 1}]}, 
  ImageSize -> 10]

And export it:

Export["square.pdf", square]

The resulting graphic in the pdf consists of both a rectangle and an edge (see image), which can be seperated in a vector-graphics software:

This leads to strange effects. Circles and Squares with the same Diameter/Edgelength are not equally big anymore. This also produces problems with Edges, as can be seen in the following example:

square = Graphics[{EdgeForm[{Red, AbsoluteThickness[1]}], Rectangle[{-1, -1}, {1, 1}]}, 
      ImageSize -> 10]

So how can I stop mathematica from producing the Edge?

Answer 1

The issue seems to have been fixed in upcoming 13.2. Meanwhile, for versions with the issue, replacing Rectangle with FilledCurve seems to be a sufficient workaround.

$Version
(*Out[]= 13.1.0 for Microsoft Windows (64-bit) (June 16, 2022)*)

orig = Graphics[{
   {EdgeForm[{Red, Thickness[.1]}], Orange, Rectangle[{-2, -2}, {2, 2}]}
   , {EdgeForm[{Blue, Thickness[.2]}], Cyan, Rectangle[{-1, -1} + .5, {1, 1} + .6]}
   , {EdgeForm[], Gray, Rectangle[{-1, -1} - .6, {1, 1} - .3]}
   }, ImageSize -> 10]

fixed = orig /. Rectangle[{xm_, ym_}, {xM_, yM_}] :> 
  FilledCurve[Line@{{xm, ym}, {xM, ym}, {xM, yM}, {xm, yM}}]

Exporting orig directly does exhibit the extra edge (as extra JoinedCurve) issue:

orig // RightComposition[
  ExportString[#, "PDF"] &
  , ImportString[#, {"PDF", "PageGraphics"}] &
  , Cases[#, FilledCurve | JoinedCurve, \[Infinity], Heads -> True] &
  , Tally
  ]
(*Out[]= {{FilledCurve, 3}, {JoinedCurve, 5}}*)

Exporting fixed seems to work:

fixed // RightComposition[
  ExportString[#, "PDF"] &
  , ImportString[#, {"PDF", "PageGraphics"}] &
  , Cases[#, FilledCurve | JoinedCurve, \[Infinity], Heads -> True] &
  , Tally
  ]
(*Out[]= {{FilledCurve, 3}, {JoinedCurve, 1}}*)

Double check in Inkscape:

Export["rect_to_FilledCurve.pdf", fixed, "PDF"]

Answer 2

In my case (Mathematica 13.1, Windows 10) it helps to specify the PlotRangeClipping and the PlotRangePadding:

square = Graphics[{EdgeForm[{Red, AbsoluteThickness[1]}], Rectangle[{-1, 
-1}, {1, 1}]}, ImageSize -> 50, PlotRangeClipping -> True, PlotRangePadding 
-> None]