R/PaletteColors.R

In ggRtsy: Add Some Van Gogh Colors and Overlay Colors on Your 'ggplot()'

#' Different color palettes created from Van Gogh paintings
#' @export
#'

gogh_palettes_pop <- list(
  `starryNight` = c("#23338C", "#30478C", "#5377A6", "#BDBF7E", "#BFA72C"), # https://uploads4.wikiart.org/00142/images/vincent-van-gogh/the-starry-night.jpg!Large.jpg
  `sunflowers` = c("#74A629", "#F2EB80", "#F2E085", "#BF9821", "#A6681C"), # https://uploads7.wikiart.org/images/vincent-van-gogh/still-life-vase-with-fifteen-sunflowers-1888-1.jpg!Large.jpg
  `selfPortrait` = c("#021F59", "#63A5BF", "#8C701C", "#BF9B6F", "#730202"), # https://uploads8.wikiart.org/images/vincent-van-gogh/self-portrait-1889-1.jpg!Large.jpg
  `wheatField` = c("#73A9D9", "#477332", "#D9B13B", "#D98E32", "#A66329"), # https://uploads4.wikiart.org/images/vincent-van-gogh/wheat-field-with-cypresses-at-the-haude-galline-near-eygalieres-1889-2.jpg!Large.jpg
  `cafeTerrace` = c("#2A6BBF", "#3F6CA6", "#F2C84B", "#D99036", "#BF6734"), # https://uploads2.wikiart.org/images/vincent-van-gogh/cafe-terrace-place-du-forum-arles-1888(1).jpg!Large.jpg
  `rhoneStarry` = c("#073359", "#27668C", "#5A98BF", "#60734D", "#A3A658"), # https://uploads0.wikiart.org/00175/images/vincent-van-gogh/starry-night-over-the-rhone.jpg!Large.jpg
  `irises` = c("#415AA6", "#6382BF", "#65A67C", "#8CA653", "#A66D58"), # https://uploads0.wikiart.org/00213/images/vincent-van-gogh/antique-3840759.jpg!Large.jpg
  `almondBlossoms` = c("#236E8C", "#20788C", "#49B3BF", "#41BFBF", "#BDBF75") # https://uploads6.wikiart.org/images/vincent-van-gogh/branches-with-almond-blossom-1890(1).jpg!Large.jpg
)

#' Interpolate the color palette
#' @param palette the ggRtsy painting color palette of choice
#' @param reverse Boolean, will be TRUE if the user wants the palette reversed
#' @param ... further arguments passed to [ggRtsy::gogh_interpolate()]
#' @export
#' @return A color interpolation function.
#'   If `reverse` is TRUE, it returns a reversed color interpolation function.
gogh_interpolate <- function(palette = "starryNight", reverse = FALSE, ...) {
  pal <- gogh_palettes_pop[[palette]]
  if (reverse == TRUE) {
    pal <- rev(pal)
  }
  grDevices::colorRampPalette(pal, ...)
}

#' Creating the color scale for Van Gogh Colors
#' @param palette the ggRtsy painting color palette of choice
#' @param reverse Boolean, will be TRUE if the user wants the palette reversed
#' @param discrete Boolean if color aesthetic is discrete
#' @param ... further arguments passed to [ggRtsy::scale_color_gogh()]
#' @examples
#' if (require(ggplot2)) {
#'   data <- data.frame(c = LETTERS[1:3],x = c(1,5,7),y = c(5,9,13))
#'   ggplot(data, aes(x,y,color = c))+geom_point()+scale_color_gogh()
#' }
#' @export
#' @return A ggplot2 color scale.
#'   If `discrete` is TRUE, it returns a discrete color scale; otherwise, a continuous color scale.
scale_color_gogh <- function(palette = "starryNight",
                             discrete = TRUE, reverse = FALSE, ...) {
  pal <- gogh_interpolate(palette, reverse)

  if (discrete == TRUE) {
    ggplot2::discrete_scale("colour", paste0("gogh_", palette), palette = pal, ...)
  } else {
    ggplot2::scale_colour_gradientn(colours = pal(256), ...) # gradient is the default for continuous
  }
}

#' Creating the color fill scale for Van Gogh Colors
#' @param palette Character name of palette in gogh_palettes_pop
#' @param discrete Boolean if color aesthetic is discrete
#' @param reverse Boolean if the palette should be reversed
#' @param ... Additional arguments used to discrete_scale() or scale_fill_gradientn()
#'   to automatically interpolate between colors.
#' @examples
#' if (require(ggplot2)) {
#'   data <- data.frame(c = LETTERS[1:3],x = c(1,5,7),y = c(5,9,13))
#'   ggplot(data, aes(x,fill=c))+geom_bar()+scale_fill_gogh()
#' }
#' @export
#' @return No return value. Called for side effects.
scale_fill_gogh <- function(palette = "sunflowers", discrete = TRUE, reverse = FALSE, ...) {
  pal <- gogh_interpolate(palette = palette, reverse = reverse)
  if (discrete) {
    ggplot2::discrete_scale("fill", paste0("gogh_", palette), palette = pal, ...)
  } else {
    ggplot2::scale_fill_gradientn(colours = pal(256), ...)
  }
}