chrome_print() landscape = T not resizing HTML Widget on print?

[andrew-fuller]

Hello.

I am creating a report in my R Shiny app that sends parameters to knit a html file and then runs chrome_print() on that to convert it to a PDF. The reason it is done this way is because I want to send my echarts4r widgets as parameters to save compute time and maintain SVG lossless quality.

The issue I am having is that when I set landscape = T it does not seem to adjust the widget to the width of the print area. It does print to the correct width when performing the operation manually through a non headless browser.

Here is a minimal example below:

R Markdown

---
title: "Untitled"
author: "fullera"
date: "`r Sys.Date()`"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
Output the plot

mtcars |>
  e_charts(cyl,renderer = 'svg') |>
  e_line(mpg) |> e_animation(show = F)

R Code

library(echarts4r)
library(pagedown)

pagedown::chrome_print(input = 'untitled.html', output = 'foo.pdf', options = list(landscape=T))

[cderv]

This is probably a problem of configuration in the websockets calls we do to chrome using the API.

Could you find time to try play with chromote and see if you have better change of finding which settings are working ? https://rstudio.github.io/chromote/

You could also see other options in chrome_print that can be set: https://chromedevtools.github.io/devtools-protocol/tot/Page/#method-printToPDF

We could then adapt what we do in pagedown accordingly.

Though, this is a complex problem of sizing before screenshoting, and it seems browser does it better. We need to find the right way to do it. I have no clue as of now.

HTML Widgets and chrome remote are hard to sync. Any help appreciated on this.

Also your example is not reproducible. It lacks proper formatting, and missing required package name. Can you update ?

Thank you !