R/stat-wb-label.R

Defines functions stat_wb_label

Documented in stat_wb_label

#' Label ranges under spectral curve.
#'
#' \code{stat_wb_label} computes computes the center of a waveband. Sets
#' suitable default aesthetics for "text" and "label"
#' geoms displaying "boundaries" and "names" of wavebands.
#'
#' @param mapping The aesthetic mapping, usually constructed with
#'   \code{\link[ggplot2]{aes}} or \code{\link[ggplot2]{aes_}}. Only needs
#'   to be set at the layer level if you are overriding the plot defaults.
#' @param data A layer specific dataset - only needed if you want to override
#'   the plot defaults.
#' @param geom The geometric object to use display the data
#' @param position The position adjustment to use for overlapping points on this
#'   layer
#' @param show.legend logical. Should this layer be included in the legends?
#'   \code{NA}, the default, includes if any aesthetics are mapped. \code{FALSE}
#'   never includes, and \code{TRUE} always includes.
#' @param inherit.aes If \code{FALSE}, overrides the default aesthetics, rather
#'   than combining with them. This is most useful for helper functions that
#'   define both data and aesthetics and shouldn't inherit behaviour from the
#'   default plot specification, e.g. \code{\link[ggplot2]{borders}}.
#' @param ... other arguments passed on to \code{\link[ggplot2]{layer}}. This
#'   can include aesthetics whose values you want to set, not map. See
#'   \code{\link[ggplot2]{layer}} for more details.
#' @param na.rm	a logical value indicating whether NA values should be stripped
#'   before the computation proceeds.
#' @param w.band a waveband object or a list of waveband objects or numeric
#'   vector of at least length two.
#' @param chroma.type character one of "CMF" (color matching function) or "CC"
#'   (color coordinates) or a \code{\link[photobiology]{chroma_spct}} object.
#' @param label.fmt character string giving a format definition for formating
#'   the name of the waveband.
#'   \code{\link{sprintf}}.
#' @param ypos.fixed numeric If not \code{NULL} used a constant value returned
#'   in \code{y}.
#'
#' @return A data frame with one row for each waveband object in the argument
#' to \code{w.band}. Wavebeand outside the range of the spectral data are
#' trimmed or discarded.
#'
#' @section Computed variables:
#' \describe{
#'   \item{x}{w.band-midpoint}
#'   \item{wb.xmin}{w.band minimum}
#'   \item{wb.xmax}{w.band maximum}
#'   \item{y}{ypos.fixed or zero}
#'   \item{wb.color}{color of the w.band}
#'   \item{wb.name}{label of w.band}
#'   \item{wb.label}{formatted wb.name}
#' }
#'
#' @section Default aesthetics:
#' Set by the statistic and available to geoms.
#' \describe{
#'   \item{label}{..wb.label..}
#'   \item{x}{..x..}
#'   \item{xmin}{..wb.xmin..}
#'   \item{xmax}{..wb.xmax..}
#'   \item{fill}{..wb.color..}
#' }
#'
#' @section Required aesthetics:
#' Required by the statistic and need to be set with \code{aes()}.
#' \describe{
#'   \item{x}{numeric, wavelength in nanometres}
#' }
#'
#' @note This stat uses a panel function and ignores grouping as it is meant to
#'   be used for annotations.
#'
#' @examples
#'
#' library(photobiologyWavebands)
#' # ggplot() methods for spectral objects set a default mapping for x and y.
#' ggplot(sun.spct) +
#'   geom_line() +
#'   stat_wb_box(w.band = VIS(), ymin = -0.04, ymax = 0,
#'   color = "black", fill = "white") +
#'   stat_wb_label(w.band = VIS(), ypos.fixed = -0.02, color = "black")
#'
#' ggplot(sun.spct) +
#'   geom_line() +
#'   stat_wb_hbar(w.band = PAR(), ypos.fixed = 0, size = 1) +
#'   stat_wb_label(aes(color = ..wb.color..),
#'                 w.band = PAR(), ypos.fixed = +0.025) +
#'   scale_color_identity()
#'
#' @export
#' @family stats functions
#'
stat_wb_label <- function(mapping = NULL,
                          data = NULL,
                          geom = "text",
                          w.band = NULL,
                          chroma.type = "CMF",
                          label.fmt = "%s",
                          ypos.fixed = 0,
                          position = "identity",
                          na.rm = TRUE,
                          show.legend = NA,
                          inherit.aes = TRUE,
                          ...) {
  ggplot2::layer(
    stat = StatWbLabel, data = data, mapping = mapping, geom = geom,
    position = position, show.legend = show.legend, inherit.aes = inherit.aes,
    params = list(w.band = w.band,
                  chroma.type = chroma.type,
                  label.fmt = label.fmt,
                  ypos.fixed = ypos.fixed,
                  na.rm = na.rm,
                  ...)
  )
}

#' @rdname gg2spectra-ggproto
#' @format NULL
#' @usage NULL
#' @export
StatWbLabel <-
  ggplot2::ggproto("StatWbLabel", ggplot2::Stat,
                   compute_panel = function(data,
                                            scales,
                                            w.band,
                                            chroma.type,
                                            label.fmt,
                                            ypos.fixed) {
                     x.range <- range(data[["x"]])
                     if (length(w.band) == 0) {
                       w.band <- waveband(x.range)
                     }
                     if (is.any_spct(w.band) ||
                         (is.numeric(w.band) && length(stats::na.omit(w.band)) >= 2)) {
                       w.band <- waveband(range(w.band, na.rm = TRUE))
                     }
                     if (!is.list(w.band) || is.waveband(w.band)) {
                       w.band <- list(w.band)
                     }
                     w.band <- trim_wl(w.band, x.range)
                     integ.df <- data.frame()
                     for (wb in w.band) {
                       if (is.numeric(wb)) { # user supplied a list of numeric vectors
                         wb <- waveband(wb)
                       }
                       range <- range(wb)
                       integ.df <-
                         rbind(integ.df,
                               tibble::tibble(x = midpoint(wb),
                                              wb.xmin = min(wb),
                                              wb.xmax = max(wb),
                                              wb.name = labels(wb)$label,
                                              wb.color = fast_color_of_wb(wb, chroma.type = chroma.type),
                                              BW.color = black_or_white(wb.color))
                         )
                     }
                     if (is.null(ypos.fixed)) {
                       integ.df[["y"]] <- 0
                     } else {
                       integ.df[["y"]] <- ypos.fixed
                     }
                     integ.df$wb.label <- sprintf(label.fmt, integ.df$wb.name)
#                     print(integ.df)
                     integ.df
                   },
                   default_aes = ggplot2::aes(label = after_stat(wb.label),
                                              y = after_stat(y),
                                              xmin = after_stat(wb.xmin),
                                              xmax = after_stat(wb.xmax),
                                              fill = after_stat(wb.color),
                                              color = after_stat(BW.color)),
                   required_aes = c("x")
  )

Try the ggspectra package in your browser

Any scripts or data that you put into this service are public.

ggspectra documentation built on Oct. 22, 2023, 1:07 a.m.