Add iTerm color scale

DESCRIPTION

@@ -9,7 +9,10 @@ Authors@R: c(
     person("Clara", "Jégousse", email = "cat3@hi.is", role = "ctb"),
     person("Hui", "Chen", email = "huichen@zju.edu.cn", role = "ctb"),
     person("Miaozhu", "Li", email = "miaozhu.li@duke.edu", role = "ctb"),
-    person("Winston", "Chang", role = c("ctb", "cph"), comment = "staticimports.R")
+    person("iTerm2-Color-Schemes contributors", role = c("ctb", "cph"),
+           comment = "iTerm2-Color-Schemes project"),
+    person("Winston", "Chang", role = c("ctb", "cph"),
+           comment = "staticimports.R")
     )
 Maintainer: Nan Xiao <me@nanx.me>
 Description: A collection of 'ggplot2' color palettes inspired by

NAMESPACE

@@ -2,6 +2,7 @@
 
 export(example_barplot)
 export(example_scatterplot)
+export(iterm_palettes)
 export(pal_aaas)
 export(pal_atlassian)
 export(pal_bmj)
@@ -13,6 +14,7 @@ export(pal_frontiers)
 export(pal_futurama)
 export(pal_gsea)
 export(pal_igv)
+export(pal_iterm)
 export(pal_jama)
 export(pal_jco)
 export(pal_lancet)
@@ -44,6 +46,7 @@ export(scale_color_frontiers)
 export(scale_color_futurama)
 export(scale_color_gsea)
 export(scale_color_igv)
+export(scale_color_iterm)
 export(scale_color_jama)
 export(scale_color_jco)
 export(scale_color_lancet)
@@ -71,6 +74,7 @@ export(scale_colour_frontiers)
 export(scale_colour_futurama)
 export(scale_colour_gsea)
 export(scale_colour_igv)
+export(scale_colour_iterm)
 export(scale_colour_jama)
 export(scale_colour_jco)
 export(scale_colour_lancet)
@@ -98,6 +102,7 @@ export(scale_fill_frontiers)
 export(scale_fill_futurama)
 export(scale_fill_gsea)
 export(scale_fill_igv)
+export(scale_fill_iterm)
 export(scale_fill_jama)
 export(scale_fill_jco)
 export(scale_fill_lancet)

NEWS.md

@@ -6,6 +6,7 @@
   and `scale_fill_primer()` (#62, #63).
 - Add the Atlassian Design System palette in `scale_color_atlassian()`
   and `scale_fill_atlassian()` (#64).
+- Add 400+ iTerm palettes in `scale_color_iterm()` and `scale_fill_iterm()` (#67).
 
 ## Improvements
 

R/discrete-iterm.R

@@ -0,0 +1,81 @@
+#' iTerm color palettes
+#'
+#' ANSI terminal color palettes sourced from the iterm2-color-schemes project.
+#' Each theme provides normal and bright variants.
+#'
+#' @param palette Palette name. See [iterm_palettes()] for available options.
+#' @param variant Variant of the palette. One of `"normal"`, `"bright"`.
+#' @param alpha Transparency level, a real number in (0, 1].
+#'   See `alpha` in [grDevices::rgb()] for details.
+#'
+#' @export pal_iterm
+#'
+#' @importFrom grDevices col2rgb rgb
+#' @importFrom scales manual_pal
+#'
+#' @references
+#' <https://github.com/mbadolato/iTerm2-Color-Schemes>
+#'
+#' @examples
+#' library("scales")
+#' show_col(pal_iterm("Rose Pine")(6))
+#' show_col(pal_iterm("Rose Pine", variant = "bright", alpha = 0.7)(6))
+pal_iterm <- function(palette = iterm_palettes(), variant = c("normal", "bright"), alpha = 1) {
+  palette <- match.arg(palette)
+  variant <- match.arg(variant)
+
+  if (alpha > 1L || alpha <= 0L) stop("alpha must be in (0, 1]")
+
+  raw_cols <- ggsci_db_iterm[[palette]][[variant]]
+  raw_cols_rgb <- col2rgb(raw_cols)
+  alpha_cols <- rgb(
+    raw_cols_rgb[1L, ], raw_cols_rgb[2L, ], raw_cols_rgb[3L, ],
+    alpha = alpha * 255L, names = names(raw_cols),
+    maxColorValue = 255L
+  )
+
+  manual_pal(unname(alpha_cols))
+}
+
+#' iTerm color scales
+#'
+#' See [pal_iterm()] for details.
+#'
+#' @inheritParams pal_iterm
+#' @param ... Additional parameters for [ggplot2::discrete_scale()].
+#'
+#' @export scale_color_iterm
+#'
+#' @importFrom ggplot2 discrete_scale
+#'
+#' @rdname scale_iterm
+#'
+#' @examples
+#' example_scatterplot() + scale_color_iterm("Rose Pine")
+#' example_barplot() + scale_fill_iterm("Rose Pine")
+scale_color_iterm <- function(palette = iterm_palettes(), variant = c("normal", "bright"), alpha = 1, ...) {
+  palette <- match.arg(palette)
+  variant <- match.arg(variant)
+  if (is_ggplot2_350()) {
+    discrete_scale("colour", palette = pal_iterm(palette, variant, alpha), ...)
+  } else {
+    discrete_scale("colour", scale_name = "iterm", palette = pal_iterm(palette, variant, alpha), ...)
+  }
+}
+
+#' @export scale_colour_iterm
+#' @rdname scale_iterm
+scale_colour_iterm <- scale_color_iterm
+
+#' @export scale_fill_iterm
+#' @importFrom ggplot2 discrete_scale
+#' @rdname scale_iterm
+scale_fill_iterm <- function(palette = iterm_palettes(), variant = c("normal", "bright"), alpha = 1, ...) {
+  palette <- match.arg(palette)
+  variant <- match.arg(variant)
+  if (is_ggplot2_350()) {
+    discrete_scale("fill", palette = pal_iterm(palette, variant, alpha), ...)
+  } else {
+    discrete_scale("fill", scale_name = "iterm", palette = pal_iterm(palette, variant, alpha), ...)
+  }
+}