Including a 3D interactive figure in html and static in word/pdf using knitr and rgl

Question

Following this question (including a interactive 3D figure with knitr) and this example by Yihui (https://dl.dropboxusercontent.com/u/15335397/misc/webgl-rmd.html), I can in

Answer 1

As pointed out in an answer to a related question, knitr 1.18 introduced the function

knitr::is_html_output()

which checks if the output is HTML. Adapting @baptiste's excellent answer to use this function:

```{r, echo=FALSE}
keep <- if(knitr::is_html_output()) 'none' else 'last'
```


```{r chunk, echo=FALSE, fig.keep=keep}
plot(cars)
if(knitr::is_html_output())
  cat("there goes fancy js code")
```

Answer 2

You could use the following setup to switch according to the output format

```{r, echo=FALSE}
out_type <- knitr::opts_knit$get("rmarkdown.pandoc.to")
keep <- if(out_type == "html") 'none' else 'last'
```


```{r chunk, echo=FALSE, fig.keep=keep}
plot(cars)
if(out_type == "html")
  cat("there goes fancy js code")
```