R/save_plot.R

In flaneuse/llamar: Plotting Functions and Styles for Livelihoods Analysis Work

#' Simple wrapper to ggsave
#' 
#' Wrapper to ggsave to auto-save the annoying fiddly arguments I always forget. Works only w/ ggplot2 objects.
#' 
# @import ggplot2 extrafont
# @importFrom data.table %like%
#' 
#' @param filename string containing file name
#' @param plot which plot to save; by default, the last one created
#' @param width width of rendered plot
#' @param height height of the rendered plot
#' @param units units of the width/height of rendered plot (typically inches -- 'in')
#' @param scale scalar factor to enlarge/shrink the rendered plot
#' @param saveBoth If TRUE, save both a .pdf and .png
#' 
#' @examples
#' # create a figure
#' p = ggplot(mtcars, aes(x = cyl, y = mpg)) + geom_point()
#' p + stat_summary(geom = 'point', fun.y = 'mean', colour = 'red', size = 5, shape = 21, fill = NA)
#' 
#' # save figures
#' save_plot('last_plot.pdf', width = 5, height = 5)
#' save_plot('plot_p.pdf', plot = p, width = 5, height = 5)
#' 


save_plot <- function(filename,
                      plot = last_plot(),
                      saveBoth = FALSE,
                      width = NA, 
                      height = NA, 
                      units = 'in', 
                      scale = 1) {
  # -- load fonts for use by pdf writer --
  extrafont::loadfonts(quiet = TRUE)
  
  if(filename %like% '.pdf'){
    
    # -- save the file as .pdf --
    ggsave(filename = filename, 
           plot,
           width = width, height = height, 
           units = units,
           bg = "transparent", 
           scale = scale,
           paper = "special", 
           useDingbats = FALSE, 
           compress = FALSE, 
           dpi = 300)
    
  } else if (filename %like% '.png') {
    # -- save the file as .png --
    ggsave(filename = filename, 
           plot,
           width = width, height = height, 
           units = units,
           bg = "transparent", 
           dpi = 300)
  } else if (saveBoth == TRUE) {
    
    # -- save the file as .pdf --
    ggsave(filename = paste0(filename, '.pdf'),
           plot,
           width = width, height = height, 
           units = units,
           bg = "transparent", 
           scale = scale,
           paper = "special", 
           useDingbats = FALSE, 
           compress = FALSE, 
           dpi = 300)
    
    # -- save the file as .png --
    ggsave(filename = paste0(filename, '.png'), 
           plot,
           width = width, height = height, 
           units = units,
           bg = "transparent", 
           dpi = 300)
  } else {
    warning('Unknown file type.  Saving as a .pdf')
    
    # -- save the file as .pdf --
    ggsave(filename = paste0(filename, '.pdf'),
           plot,
           width = width, height = height, 
           units = units,
           bg = "transparent", 
           scale = scale,
           paper = "special", 
           useDingbats = FALSE, 
           compress = FALSE, 
           dpi = 300)
  }
}