Feature request: Provide multiple output formats to IJulia

[benz0li]

Currently, only one output format is provided: png by default; otherwise what is set by the activate! function (e.g. CairoMakie.activate!(type = "svg"), but only if there is a match with https://github.com/JuliaLang/IJulia.jl/blob/1cdaf7e5e65c1221b4a3fac86f63253bea65a0c5/src/display.jl#L19-L28.

Please provide every MIME type specified in the first level of that vector. 👉 After executing IJulia.register_mime(MIME("application/pdf")) I would like Makie.js (CairoMakie) to return both image/svg+xml and application/pdf.

This allows IJulia to use

• image/svg+xml for plot display in the browser + HTML conversion using SVG
• application/pdf for direct PDF conversion

---

See https://github.com/JuliaPlots/Plots.jl/issues/4288 about the same feature request for Plots.jl.

[benz0li]

Cross references:

• https://github.com/JuliaPlots/Plots.jl/pull/4188
  • https://github.com/JuliaLang/IJulia.jl/issues/1035
  • https://github.com/JuliaLang/IJulia.jl/pull/1038#issuecomment-1194523666
• https://github.com/jupyter/docker-stacks/issues/1754
  ℹ️ With application/pdf plot format in the notebook file, inkscape is not required for PDF conversion using nbconvert.
  • https://github.com/jupyter/docker-stacks/pull/1765

[jkrumbiegel]

One problem is that for some plots with lots of data points, vector graphics become very large and slow. In those cases bitmaps are desirable, but even though CairoMakie uses png by default, it seems that IJulia still saves an svg for every plot and displays that because it is ranked higher.

[benz0li]

One problem is that for some plots with lots of data points, vector graphics become very large and slow. In those cases bitmaps are desirable,

Agreed. Execution time (Intel® Xeon® Silver 4210R CPU @ 2.40GHz) for https://lazarusa.github.io/BeautifulMakie/withTheme/theme_dark_astronauts/ [all packages installed and precompiled]:

• png: 2m 32.1s (size: 1.1 MB)
• svg: 14m 15s (size: 19.3 MB)
• pdf: 2m 35s (size: 1.2 MB)

ℹ️ JupyterLab is able to display the svg while code-server fails miserably.

[benz0li]

but even though CairoMakie uses png by default, it seems that IJulia still saves an svg for every plot and displays that because it is ranked higher.

I can't confirm that. You may login at https://demo.jupyter.b-data.ch with your GitHub account, Start image Julia (pubtools:latest) + code-server and execute the following as a Jupyter notebook (.ipynb)

Pkg.add("CairoMakie")

IJulia.ijulia_mime_types

import CairoMakie

x = range(0, 10, length = 100)
y = sin.(x)
CairoMakie.lines(x, y)

in JupyterLab or code-server; whatever you prefer.

If you then cat the .ipynb file in the Terminal, cells.outputs.data of the last cell contains image/png and text/plain only.
ℹ️ IJulia does not do any image conversion on its own.

[SimonDanisch]

Feel free to open a PR with those changes! I don't think we currently have the resources to work on this!

[benz0li]

The issue is now described in detail and the solution a nice to have. I currently do not have the resources to fix this either.

I will see if I can contribute something at a later date.

P.S.: Makie is great!

[ffreyer]

Looks like you can set type in CairoMakie.activate!() now... Can this be closed?

[asinghvi17]

No, the question is asking for all possible formats to be marked showable/actually shown so Jupyter has access to png, svg and pdf output.