R/noMargins.R

In delta-rho/trelliscope: Create and Navigate Large Multi-Panel Visual Displays

#' Remove Margins from Trellis/Lattice Plot
#'
#' Removes whitespace surrounding a trellis plot.  Ideal for \code{\link{makeDisplay}} because when tiling multiple panels, a lot of space is wasted with the margins.
#'
#' @param \ldots a list of other parameters to be passed to par.settings
#' @param topkey should extra space be added for a top key?
#' @param rightkey should extra space be added for a right key?
#'
#' @seealso \code{\link[lattice]{xyplot}}, \code{\link{makeDisplay}}
#'
#' @examples
#' \dontrun{
#' library(lattice)
#' xyplot(c(1:10) ~ c(1:10) | sample(letters[1:2], 10, replace=TRUE),
#'   par.settings=noMargins()
#' )
#'
#' # with additional par.settings...
#' xyplot(c(1:10) ~ c(1:10) | sample(letters[1:2], 10, replace = TRUE),
#'   par.settings = noMargins(
#'     list(plot.symbol = list(col = "black"))
#'   )
#' )
#' }
#'
#' @export
noMargins <- function(..., topkey = FALSE, rightkey = FALSE) {

  nmlist <- list(
    layout.heights = list(
      top.padding = 0,
      main.key.padding = 0,
      key.axis.padding = 0,
      axis.xlab.padding = 0,
      xlab.key.padding = 0,
      key.sub.padding = 0,
      bottom.padding = 0.5
    ),
    layout.widths = list(
      left.padding = 0,
      key.ylab.padding = 0,
      ylab.axis.padding = 0,
      axis.key.padding = 0,
      right.padding = 0.6
    ),
    axis.components = list(
      top = list(pad1 = ifelse(topkey, 2, 1), pad2 = ifelse(topkey, 2, 0)), # padding above top axis
      right = list(pad1 = 0, pad2 = 0)
    )
  )
  # TODO: allow "..." to override any elements in "nmlist"
  c(nmlist, ...)
}