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#' Read colors from Adobe Color (ACO) files
#'
#' Given a path or URL to an \code{.aco} file, this function will return
#' a named character vector (if color names are present) of hex RGB colors.
#'
#' @param path partial or full file path or URL to an ACO file
#' @param use_names add color names to the vector (defaults to \code{TRUE}). See NOTE
#' @param .verbose show extra information about ACO file processing#' @export
#' @note When using named color palettes in a \code{ggplot2} \code{scale_} context, you
#' must \code{unname} them or set \code{use_names} to \code{FALSE}.
#' Not sure if this is a bug or a deliberate feature in ggplot2. Also, Neither Lab nor
#' greyscale colors are supported.
#' @export
#' @examples \dontrun{
#' # built-in palette
#' eighties <- read_ase(system.file("palettes",
#' "tomorrow_night_eighties.aco", package="swatches"))
#' print(eighties)
#' show_palette(eighties)
#'
#' # from the internet directly
#' tomorrow_night <- read_ase("l.dds.ec/tomorrow-night-aco")
#' print(tomorrow_night)
#' show_palette(tomorrow_night)
#' }
read_aco <- function(path, use_names=TRUE, .verbose=FALSE) {
if (is_url(path)) {
tf <- tempfile()
stop_for_status(GET(path, write_disk(tf)))
path <- tf
}
aco <- readBin(path.expand(path), "raw",
file.info(path.expand(path))$size, endian="big")
version <- unpack("v", aco[2:1])[[1]]
n_colors <- unpack("v", aco[4:3])[[1]]
if (.verbose) {
message("ACO Version: ", version)
message("# Colors: " , n_colors)
}
pal <- NULL
if (version == 1) {
pal <- decode_aco_v1(aco, n_colors)
} else {
pal <- decode_aco_v2(aco, n_colors)
}
if (!use_names) { pal <- unname(pal) }
pal
}
#' Read colors from Adobe Swatch Exchange (ASE) files
#'
#' Given a path or URL to an \code{.ase} file, this function will return
#' a named character vector (if color names are present) of hex RGB colors.
#'
#' @param path partial or full file path or URL to an ASE file
#' @param use_names add color names to the vector (defaults to \code{TRUE}). See NOTE
#' @param .verbose show extra information about ASE file processing
#' @note When using named color palettes in a \code{ggplot2} \code{scale_} context, you
#' must \code{unname} them or set \code{use_names} to \code{FALSE}.
#' Not sure if this is a bug or a deliberate feature in ggplot2. Also, Neither Lab nor
#' greyscale colors are supported.
#' @export
#' @examples
#' \dontrun{
#' # built in palette
#' keep_the_change <- read_ase(system.file("palettes",
#' "keep_the_change.ase", package="swatches"))
#' print(keep_the_change)
#' show_palette(keep_the_change)
#'
#' # from the internet directly
#' github <- "https://github.com/picwellwisher12pk/en_us/raw/master/Swatches/Metal.ase"
#' metal <- read_ase(github)
#' print(metal)
#' show_palette(metal)
#' }
read_ase <- function(path, use_names=TRUE, .verbose=FALSE) {
if (is_url(path)) {
tf <- tempfile()
stop_for_status(GET(path, write_disk(tf)))
path <- tf
}
ase <- readBin(path, "raw",
file.info(path.expand(path))$size, endian="big")
if (unpack("A4", ase[1:4])[[1]] != "ASEF") {
message("Not a valid ASE file")
stop()
}
version <- sprintf("%d.%d", b2i(ase[5:6]), b2i(ase[7:8]))
block_count <- b2li(ase[9:12])
if (.verbose) {
message("ASE Version: ", version)
message("Block count: ", block_count)
}
pal <- decode_ase(ase, block_count)
if (!use_names) { pal <- unname(pal) }
pal
}
#' Display a color palette
#'
#' Given a character vector (hex RGB values), display palette in graphics window.
#'
#' @param palette vector of character hex RGB values
#' @export
#' @examples
#' \dontrun{
#' # built in palette
#' keep_the_change <- read_ase(system.file("palettes",
#' "keep_the_change.ase", package="swatches"))
#' print(keep_the_change)
#' show_palette(keep_the_change)
#' }
show_palette <- function(palette) {
n <- length(palette)
if (length(palette > 0)) {
image(1:n, 1, as.matrix(1:n), col = palette,
xlab = "", ylab = "", xaxt = "n", yaxt = "n",
bty = "n")
}
}