PDF version used when saving a figure in CairoMakie

I have a technical question about the PDF version that is used when CairoMakie saves a figure. I notice CairoMakie saves using PDF version 1.5[1]. When I combine several assets together in, say, Affinity Publisher to create a poster or combined graphic, it does a pre-flight compatibility check[2]. This matters if the assets all use different pdf versions or the final exported version is different from the versions of the individual assets. Usually there are no problems, but sometimes parts of assets are not rendered or are not rendered correctly. Trying to convert to different versions can cause problems, particularly with fonts. For example, superscript unicode characters in CairoMakie will be out of place or look undesirable if a figure is converted from PDF version 1.5 to 1.7 with the default font.

Is there a way to specify which PDF version CairoMakie exports to? Or is that an intrinsic part of the cairo software?

  1. Using cairo 1.16.0 as of the latest version of Makie v0.19.7 ↩︎

  2. The highest PDF version that can be exported in Affinity Publisher is 1.7 ↩︎

Seems like one can restrict to 1.4 but 1.5 is the highest available PDF Surfaces: Cairo: A Vector Graphics Library

Interesting. Thanks!