Add plot and print methods for Picture and array objects

NAMESPACE

@@ -2,6 +2,10 @@
 
 S3method(flip_phylopic,Picture)
 S3method(flip_phylopic,array)
+S3method(plot,Picture)
+S3method(plot,phylopic)
+S3method(print,Picture)
+S3method(print,phylopic)
 S3method(recolor_phylopic,Picture)
 S3method(recolor_phylopic,array)
 S3method(rotate_phylopic,Picture)

NEWS.md

@@ -5,6 +5,7 @@
 * added browse_phylopic function (#60)
 * added preview argument to get_phylopic (#59)
 * switched to {maps} package in base R advanced vignette
+* added plot and print methods for silhouette objects (#73)
 
 # rphylopic 1.1.1
 

R/get_phylopic.R

@@ -74,6 +74,7 @@ get_phylopic <- function(uuid = NULL, format = "vector", height = 512,
       # use the svg to make a png with the desired height
       img <- readPNG(rsvg_png(image_info$vectorFile$href, height = height))
     }
+    class(img) <- c("phylopic", class(img))
   } else if (format == "vector") { # get vector
     url <- image_info$vectorFile$href
     img <- get_svg(url)

R/phylopic_utils.R

@@ -259,3 +259,47 @@ recolor_content <- function(x, alpha, color, remove_background) {
   x@content <- Filter(function(element) !is.null(element), tmp)
   return(x)
 }
+
+#' Plot a vector representation of a PhyloPic silhouette
+#' @param img A [Picture][grImport2::Picture-class] object, e.g., from using
+#'   [get_phylopic()].
+#' @param ... Other arguments passed on to [grImport2::grid.picture()].
+#' @importFrom grid grid.newpage
+#' @importFrom grImport2 grid.picture
+#' @export
+plot.Picture <- function(img, ...) {
+  grid.newpage()
+  grid.picture(img, ...)
+}
+
+#' Plot a raster representation of a PhyloPic silhouette
+#' @param img A png array object, e.g., from using [get_phylopic()].
+#' @param ... Other arguments passed on to [grid::grid.raster()].
+#' @importFrom grid grid.newpage grid.raster
+#' @export
+plot.phylopic <- function(img, ...) {
+  grid.newpage()
+  grid.raster(img, ...)
+}
+
+#' @export
+print.Picture <- function(img) {
+  dims <- c(abs(diff(img@summary@xscale)), abs(diff(img@summary@yscale)))
+  cat(paste0("Vector representation of a PhyloPic silhouette.",
+             "\nDimensions: ", dims[1], " pixels wide and ",
+             dims[2], " pixels tall.",
+             "\nuuid: ", attr(img, "uuid"),
+             "\nURL: ", attr(img, "url")))
+  invisible(img)
+}
+
+#' @export
+print.phylopic <- function(img) {
+  dims <- dim(img)
+  cat(paste0("Raster representation of a PhyloPic silhouette.",
+             "\nDimensions: ", dims[2], " pixels wide and ",
+             dims[1], " pixels tall.",
+             "\nuuid: ", attr(img, "uuid"),
+             "\nURL: ", attr(img, "url")))
+  invisible(img)
+}