provide tools for recording and then playing back tidytuesday plot generation! (Assumes you are using ggplot)

tt_record and tt_playback

tt_recording_env <- new.env()


tt_record <- function(dir = tempdir(), 
                      device = c("png", "jpeg", "bmp", "tiff", "emf", "svg", "eps"), 
                      scale = 1, 
                      width = NA,
                      height = NA,
                      units = c("in", "cm", "mm"),
                      dpi = 300,
                      limitsize = TRUE
                      ){
  
  if(!dir.exists(dir)){
    dir.create(dir,recursive = TRUE)
  }else{
    if(length(list.files(dir) > 1)){
      warning("Writing to a folder that already exists, and tt_playback may grab more files than intended!")
    }
  }
  
  device <- match.arg(device)
  units <- match.arg(units)
  
  tt_recording_env$recording_dir <- dir
  tt_recording_env$device <- device
  
  ## create shim function
  
  tt_recording_env$print.view_and_save_ggplot <-
    function(x,
             newpage = is.null(vp),
             vp = NULL,
             ...) {
      
    # View plot
    ggplot2:::print.ggplot(x, newpage = newpage, vp = vp, ...)
    
    plot_file <- file.path(dir,paste0(format(Sys.time(), "%Y_%m_%d_%H_%M_%S"),".",device))
    
    suppressMessages({
      ggplot2:::ggsave(
        filename = plot_file,
        plot = x,
        scale = scale,
        width = width,
        height = height,
        units = units,
        dpi = dpi,
        limitsize = limitsize
      )
    })
    
    invisible(x)
    
  }
  
  registerS3method(
    genname = "print",
    class = "ggplot",
    method = "print.view_and_save_ggplot",
    envir = tt_recording_env
  )
}

tt_playback <- function(name = NULL,..., stoprecording = TRUE){
  
  records <- list.files(
    path    = tt_recording_env$recording_dir,
    pattern = paste0("*.",tt_recording_env$device,"$"),
    full.names = TRUE)
  
  
  if(is.null(name)){
  recording <-
    file.path(tt_recording_env$recording_dir, 
              paste0(format(Sys.time(), "%Y_%m_%d_%H_%M_%S"), ".gif"))
  }else{
    recording <- name
  }
  
  gifski::gifski(
    records,
    gif_file = recording,
    ...
  )
  
  viewer <- getOption("viewer", utils::browseURL)
  
  if (is.function(viewer) && length(recording)) {
    viewer(recording)
  } 
  
  if(stoprecording){
    
    registerS3method(
      genname = "print",
      class = "ggplot",
      method = "print.ggplot",
      envir = getNamespace("ggplot2")
    )

  }

  invisible()
  
}




library(ggplot2)


tt_record(dir = "test_gg_record")

ggplot(data.frame(x = 1, y = 1)) + geom_point(aes(x,y)) + ylim(0,5)
ggplot(data.frame(x = 1, y = 2)) + geom_point(aes(x,y)) + ylim(0,5)
ggplot(data.frame(x = 1, y = 3)) + geom_point(aes(x,y)) + ylim(0,5)
ggplot(data.frame(x = 1, y = 4)) + geom_point(aes(x,y)) + ylim(0,5)

tt_playback()