R/BG.R

In OpenIntroStat/openintro-r-package: Data Sets and Supplemental Functions from 'OpenIntro' Textbooks and Labs

#' Add background color to a plot
#'
#' Overlays a colored rectangle over the entire plotting region.
#'
#'
#' @param col Color to overlay.
#' @seealso \code{\link{COL}}
#' @export
#' @examples
#'
#' Test <- function(col) {
#'   plot(1:7,
#'     col = COL[1:7], pch = 19, cex = 5,
#'     xlim = c(0, 8),
#'     ylim = c(0, 9)
#'   )
#'   BG(col)
#'   points(2:8, col = COL[1:7], pch = 19, cex = 5)
#'   text(2, 6, "Correct Color")
#'   text(6, 2, "Affected Color")
#' }
#'
#' # Works well since black color almost fully transparent
#' Test(COL[5, 9])
#'
#' # Works less well since transparency isn't as significant
#' Test(COL[5, 6])
#'
#' # Pretty ugly due to overlay
#' Test(COL[5, 3])
#'
#' # Basically useless due to heavy color gradient
#' Test(COL[4, 2])
BG <- function(col = openintro::COL[5, 9]) {
  rect(
    graphics::par("usr")[1],
    graphics::par("usr")[3],
    graphics::par("usr")[2],
    graphics::par("usr")[4],
    col = col,
    border = NA
  )
}