SmoothSproll没有锚点(Smoothscroll without anchors)

 所以，这就是我想出来的。 添加绘图钩子，以便在生成块中的小图像之前生成全分辨率的pdf图像： 
 
allow_thumbnails <- function(x, options) {
  if (!is.null(options$thumb)) {
    filename <- sprintf("%s.full.pdf", strsplit(basename(x), "\\.")[[1]][1])
    absolute_path <- file.path(dirname(x), filename)

    # generate the full resolution pdf
    pdf(absolute_path, width = options$thumb$width, height = options$thumb$height)
      eval(parse(text = options$code))
    dev.off()

    # add an html link to the low resolution png
    options$fig.link = absolute_path
  }

  knitr:::hook_plot_md_base(x, options)
}
 
 然后在Rmd文件中，我使用thumb参数定义全分辨率图像的大小： 
 
```{r init} 
    knit_hooks$set(plot = allow_thumbnails)
```

```{r my_large_plot, fig.width = 15, fig.height = 15, thumb = list(width = 45, height = 45)}
    my_large_plot()
```
 
 这会生成一个带有可点击的png的html文件，可将您带到pdf中。 

So, this is what I came up with. Add a plot hook, so that you generate a full-resolution pdf image before generating a small image in the chunk:
 
allow_thumbnails <- function(x, options) {
  if (!is.null(options$thumb)) {
    filename <- sprintf("%s.full.pdf", strsplit(basename(x), "\\.")[[1]][1])
    absolute_path <- file.path(dirname(x), filename)

    # generate the full resolution pdf
    pdf(absolute_path, width = options$thumb$width, height = options$thumb$height)
      eval(parse(text = options$code))
    dev.off()

    # add an html link to the low resolution png
    options$fig.link = absolute_path
  }

  knitr:::hook_plot_md_base(x, options)
}
 
And then in the Rmd file, I define the size of the full-resolution image using the thumb argument:
 
```{r init} 
    knit_hooks$set(plot = allow_thumbnails)
```

```{r my_large_plot, fig.width = 15, fig.height = 15, thumb = list(width = 45, height = 45)}
    my_large_plot()
```
 
This generates an html file with a clickable png that takes you to the pdf.