R/plots.R

In resourcecode: Access to the 'RESOURCECODE' Hindcast Database

#' Create a map of the provided variable on the RESOURCECODE field grid
#'
#' @param z the data ro plot: a vector of the same size as the grid (328,030 rows).
#' @param name name of the variable plored, to be included in the legend.
#' @param zlim limits of the scale. See \code{\link[ggplot2]{continuous_scale}} for details.
#' @param palette If a string, will use that named palette.
#' See \code{\link[ggplot2]{scale_colour_brewer}} for other options.
#' @param direction Sets the order of colours in the scale.
#' See \code{\link[ggplot2]{scale_colour_brewer}} for details.
#' @param transform  Transformation to apply to the color scale.
#' See \code{\link[ggplot2]{continuous_scale}} for details.
#'
#' @return a ggplot2 object
#' @export
#'
#' @examples
#' # Ensure that data package is available before running the example.
#' # If it is not, see the `resourcecode` package vignette for details
#' # on installing the required data package.
#' if (requireNamespace("resourcecodedata", quietly = TRUE)) {
#'   rscd_mapplot(resourcecodedata::rscd_field$depth)
#' }
rscd_mapplot <- function(z,
                         name = "Depth (m)",
                         zlim = NULL,
                         palette = "YlOrRd",
                         direction = 1,
                         transform = "identity") {
  has_data()

  xyzgz <- tibble::tibble(
    x = resourcecodedata::rscd_field$longitude[resourcecodedata::rscd_triangles],
    y = resourcecodedata::rscd_field$latitude[resourcecodedata::rscd_triangles],
    z = z[resourcecodedata::rscd_triangles],
    g = rep(seq_len(ncol(
      resourcecodedata::rscd_triangles
    )), each = nrow(resourcecodedata::rscd_triangles))
  )

  ggplot(
    data = xyzgz,
    aes(
      .data$x,
      .data$y,
      group = .data$g,
      fill = .data$z,
      col = .data$z
    )
  ) +
    geom_polygon() +
    scale_fill_distiller(
      name = name,
      palette = palette,
      na.value = "transparent",
      limits = zlim,
      direction = direction,
      transform = transform
    ) +
    scale_color_distiller(
      guide = "none",
      palette = palette,
      na.value = "transparent",
      limits = zlim,
      direction = direction,
      transform = transform
    ) +
    geom_path(
      data = resourcecodedata::rscd_coastline,
      aes(x = .data$longitude, y = .data$latitude),
      linewidth = .2,
      inherit.aes = FALSE
    ) +
    geom_path(
      data = resourcecodedata::rscd_islands,
      aes(
        x = .data$longitude,
        y = .data$latitude,
        group = .data$ID
      ),
      linewidth = .2,
      inherit.aes = FALSE
    ) +
    coord_sf(expand = FALSE, crs = sf::st_crs(4326)) +
    theme_void() +
    theme(
      legend.position = "inside",
      legend.position.inside = c(.8, 0.2),
      legend.margin = margin(
        t = 0,
        r = 0,
        b = 0,
        l = 0,
        unit = "pt"
      ),
      plot.margin = margin(
        t = 0,
        r = 0,
        b = 0,
        l = 0,
        unit = "pt"
      ),
      axis.text.x = element_blank(),
      axis.ticks.x = element_blank(),
      axis.text.y = element_blank(),
      axis.ticks.y = element_blank(),
      panel.border = element_rect(
        color = "black",
        fill = NA,
        linewidth = 1
      )
    )
}