R/si_style.R

In USAID-OHA-SI/glitr: Adorned SI style plots

#' @title Create Standard SI Plots
#'
#' @description This function adorns your ggplot to convert it into a SI style plot. The default font is Source Sans Pro
#' @param font_title font family for titles, defaults to Source Sans Pro/Arial
#' @param font_subtitle font family for subtitles, defaults to Source Sans Pro/Arial
#' @param font_plot font family for the plot space, defaults to Source Sans Pro/Arial
#' @param font_caption font family for captions, defaults to Source Sans Pro/Arial
#' @param facet_space controls how far apart facets are from each other
#' @param text_scale scalar that will grow/shrink all text defined within
#' @param FO make everything black (why, who knows)
#' @param ... pass any parameters from theme that are not already defined within
#'
#' @export
#' @importFrom magrittr %>%
#' @importFrom ggplot2 %+replace% aes geom_point theme_minimal theme
#'
#' @examples
#' \dontrun{
#' library(systemfonts)
#' library(ggplot2)
#' ggplot(iris, aes(Sepal.Length, y = Sepal.Width, colour = Species)) +
#'   geom_point() + si_style()
#'   }


si_style <- function(font_title,
                     font_subtitle,
                     font_plot,
                     font_caption,
                     facet_space = 2,
                     text_scale = 1,
                     FO = FALSE,
                     ...) {

  if(!isNamespaceLoaded("systemfonts"))
    cli::cli_alert_warning("The {.pkg systemfonts} package is not loaded. Run {.code library(systemfonts)}")

  if(isNamespaceLoaded("extrafont"))
    cli::cli_alert_warning("The {.pkg extrafont} package is loaded. Remove this library and restart your session as it conflicts with {.pkg systemfonts}")

  if(is.null(getOption('glitr_font')))
    choose_font()

  glitr_font_default <- getOption('glitr_font')

  if(missing(font_title))
    font_title <- glitr_font_default
  if(missing(font_subtitle))
    font_subtitle <- glitr_font_default
  if(missing(font_plot))
    font_plot <- glitr_font_default
  if(missing(font_caption))
    font_caption <- glitr_font_default

  half_line <- 5.5

  if(FO == TRUE) {
    # Use only black colors b/c grey color non gray
    color_plot_text <- "#000000"
    color_title <- "#000000"
    color_caption <- "#000000"

    ggplot2::theme_minimal() %+replace%

      ggplot2::theme(
        plot.title = ggplot2::element_text(
          family = font_title,
          size = 14 * text_scale,
          face = "bold",
          color = color_title,
          margin = ggplot2::margin(b = half_line),
          hjust = 0),

        #This sets the font, size, type and colour of text for the chart's subtitle, as well as setting a margin between the title and the subtitle
        plot.subtitle = ggplot2::element_text(
          family = font_subtitle,
          size = 12  * text_scale,
          color = color_title,
          margin = ggplot2::margin(b = half_line),
          hjust = 0),
        plot.caption = ggplot2::element_text(
          family = font_caption,
          size = 9 * text_scale,
          color = color_caption,
          margin = ggplot2::margin(t = half_line/2),
          hjust = 1, vjust = 1),
        plot.margin = ggplot2::margin(15, 15, 10, 15), #top, right, bottom, left
        plot.title.position = "plot", #Move plot.title to the left
        plot.caption.position = "plot",

        #Legend format
        # Set the legend to be at the top left of the graphic, below title
        legend.position = "top",
        legend.text.align = 0,
        legend.justification = c(0, 0),
        legend.background = ggplot2::element_blank(),
        #legend.title = ggplot2::element_blank(),
        legend.key = ggplot2::element_blank(),
        legend.title = ggplot2::element_text(
          family = font_title,
          size = 11 * text_scale,
          color = color_plot_text),
        legend.text = ggplot2::element_text(
          family = font_title,
          size = 11 * text_scale,
          color = color_plot_text),

        #Axis format
        axis.text = ggplot2::element_text(
          family = font_plot,
          size = 10 * text_scale,
          color = color_plot_text),
        axis.ticks = ggplot2::element_blank(),
        axis.line = ggplot2::element_blank(),
        axis.title = ggplot2::element_text(
          family = font_plot,
          size = 10 * text_scale,
          colour = color_plot_text),

        #Grid lines
        panel.grid.minor = ggplot2::element_blank(),
        panel.grid.major.y = ggplot2::element_line(colour = color_gridline, linewidth = 0.25),
        panel.grid.major.x = ggplot2::element_line(colour = color_gridline, linewidth = 0.25),

        #Blank background
        panel.background = ggplot2::element_blank(),
        panel.border = ggplot2::element_blank(),
        panel.spacing = ggplot2::unit(facet_space, "lines"),

        # Plot fill and margins
        plot.background = ggplot2::element_rect(fill = "white", color = NA),

        #Strip background (This sets the panel background for facet-wrapped plots to white)
        strip.background = ggplot2::element_blank(),
        strip.text = ggplot2::element_text(
          family = font_title,
          size  = 11 * text_scale,
          hjust = 0,
          color = color_plot_text,
          margin = ggplot2::margin(0.6 * half_line, 0.6 * half_line, 0.6 * half_line, 0.6 * half_line)
        ),
        ...
      )
  }

  # build off of theme_minimal settings
  ggplot2::theme_minimal() %+replace%

    ggplot2::theme(
      plot.title = ggplot2::element_text(
        family = font_title,
        size = 14 * text_scale,
        face = "bold",
        color = color_title,
        margin = ggplot2::margin(b = half_line),
        hjust = 0),

      #This sets the font, size, type and colour of text for the chart's subtitle, as well as setting a margin between the title and the subtitle
      plot.subtitle = ggplot2::element_text(
        family = font_subtitle,
        size = 12  * text_scale,
        color = color_title,
        margin = ggplot2::margin(b = half_line),
        hjust = 0),
      plot.caption = ggplot2::element_text(
        family = font_caption,
        size = 9 * text_scale,
        color = color_caption,
        margin = ggplot2::margin(t = half_line/2),
        hjust = 1, vjust = 1),
      plot.margin = ggplot2::margin(15, 15, 10, 15), #top, right, bottom, left
      plot.title.position = "plot", #Move plot.title to the left
      plot.caption.position = "plot",

      #Legend format
      # Set the legend to be at the top left of the graphic, below title
      legend.position = "top",
      legend.text.align = 0,
      legend.justification = c(0, 0),
      legend.background = ggplot2::element_blank(),
      #legend.title = ggplot2::element_blank(),
      legend.key = ggplot2::element_blank(),
      legend.title = ggplot2::element_text(
        family = font_title,
        size = 11 * text_scale,
        color = color_plot_text),
      legend.text = ggplot2::element_text(
        family = font_title,
        size = 11 * text_scale,
        color = color_plot_text),

      #Axis format
      axis.text = ggplot2::element_text(
        family = font_plot,
        size = 10 * text_scale,
        color = color_plot_text),
      axis.ticks = ggplot2::element_blank(),
      axis.line = ggplot2::element_blank(),
      axis.title = ggplot2::element_text(
        family = font_plot,
        size = 10 * text_scale,
        colour = color_plot_text),

      #Grid lines
      panel.grid.minor = ggplot2::element_blank(),
      panel.grid.major.y = ggplot2::element_line(colour = color_gridline, linewidth = 0.25),
      panel.grid.major.x = ggplot2::element_line(colour = color_gridline, linewidth = 0.25),

      #Blank background
      panel.background = ggplot2::element_blank(),
      panel.border = ggplot2::element_blank(),
      panel.spacing = ggplot2::unit(facet_space, "lines"),

      # Plot fill and margins
      plot.background = ggplot2::element_rect(fill = "white", color = NA),


      #Strip background (This sets the panel background for facet-wrapped plots to white)
      strip.background = ggplot2::element_blank(),
      strip.text = ggplot2::element_text(
        family = font_title,
        size  = 11 * text_scale,
        hjust = 0,
        color = color_plot_text,
        margin = ggplot2::margin(0.6 * half_line, 0.6 * half_line, 0.6 * half_line, 0.6 * half_line)
      ),
      ...
    )
}