R/theme-duncan.R

In dungates/DGThemes: Additional Themes, Theme Components and Utilities for 'ggplot2'

#' A precise & pristine [ggplot2] theme with opinionated defaults and an emphasis on typography
#'
#' Also has a "dark" / "modern" version for the new RStudio theme
#'
#' @md
#' @section Why Open Sans?:
#' First and foremost, Open Sans is generally installed by default or readily
#' available on any modern system, so it's "free"-ish; plus, it is a condensed font
#' with solid default kerning pairs and geometric numbers.
#'
#' @section Building upon `theme_duncan`:
#' The function is setup in such a way that you can customize your own one by just
#' wrapping the call and changing the parameters. See source for examples.
#'
#' @section Gotchas:
#' There are distinctions between font names and various devices. Names that work
#' for display graphics devices and bitmap ones such as `png` may not work well
#' for PostScript or PDF ones. You may need two versions of a font-based
#' theme function for them to work in a particular situation. This situation
#' usually only arises when using a newer font with many weights but somewhat
#' irregular internal font name patterns.
#'
#' There is an option `DGThemes.loadfonts` which -- if set to `TRUE` -- will
#' call `extrafont::loadfonts()` to register non-core fonts with R PDF & PostScript
#' devices. If you are running under Windows, the package calls the same function
#' to register non-core fonts with the Windows graphics device.
#'
#' @md
#' @param base_family,base_size base font family and size
#' @param plot_title_family,plot_title_face,plot_title_size,plot_title_margin plot title family, face, size and margi
#' @param subtitle_family,subtitle_face,subtitle_size plot subtitle family, face and size
#' @param subtitle_margin plot subtitle margin bottom (single numeric value)
#' @param strip_text_family,strip_text_face,strip_text_size facet label font family, face and size
#' @param caption_family,caption_face,caption_size,caption_margin plot caption family, face, size and margin
#' @param axis_title_family,axis_title_face,axis_title_size axis title font family, face and size
#' @param axis_title_just axis title font justification, one of `[blmcrt]`
#' @param plot_margin plot margin (specify with `ggplot2::margin()`)
#' @param grid_col,axis_col grid & axis colors; both default to `#cccccc`
#' @param grid panel grid (`TRUE`, `FALSE`, or a combination of `X`, `x`, `Y`, `y`)
#' @param axis_text_size font size of axis text
#' @param axis add x or y axes? `TRUE`, `FALSE`, "`xy`"
#' @param ticks ticks if `TRUE` add ticks
#' @export
#' @examples \dontrun{
#' library(ggplot2)
#' library(dplyr)
#'
#' # seminal scatterplot
#' ggplot(mtcars, aes(mpg, wt)) +
#'   geom_point() +
#'   labs(
#'     x = "Fuel efficiency (mpg)", y = "Weight (tons)",
#'     title = "Seminal ggplot2 scatterplot example",
#'     subtitle = "A plot that is only useful for demonstration purposes",
#'     caption = "Brought to you by the letter 'g'"
#'   ) +
#'   theme_duncan()
#'
#' # seminal bar chart
#'
#' update_geom_font_defaults()
#'
#' count(mpg, class) %>%
#'   ggplot(aes(class, n)) +
#'   geom_col() +
#'   geom_text(aes(label = n), nudge_y = 3) +
#'   labs(
#'     x = "Fuel efficiency (mpg)", y = "Weight (tons)",
#'     title = "Seminal ggplot2 bar chart example",
#'     subtitle = "A plot that is only useful for demonstration purposes",
#'     caption = "Brought to you by the letter 'g'"
#'   ) +
#'   theme_duncan(grid = "Y") +
#'   theme(axis.text.y = element_blank())
#' }
theme_duncan <- function(base_family = "Open Sans",
                         base_size = 11.5,
                         plot_title_family = "Fira Sans",
                         plot_title_size = 18,
                         plot_title_face = "bold",
                         plot_title_margin = 10,
                         subtitle_family = "Fira Sans",
                         subtitle_size = 12,
                         subtitle_face = "plain",
                         subtitle_margin = 15,
                         strip_text_family = base_family,
                         strip_text_size = 12,
                         strip_text_face = "bold",
                         caption_family = base_family,
                         caption_size = 9,
                         caption_face = "italic",
                         caption_margin = 10,
                         axis_text_size = base_size,
                         axis_title_family = subtitle_family,
                         axis_title_size = 9,
                         axis_title_face = "plain",
                         axis_title_just = "rt",
                         plot_margin = margin(30, 30, 30, 30),
                         grid_col = "#cccccc",
                         grid = TRUE,
                         axis_col = "#cccccc",
                         axis = FALSE,
                         ticks = FALSE) {
  ret <- ggplot2::theme_minimal(base_family = base_family, base_size = base_size)

  ret <- ret + theme(legend.background = element_blank())
  ret <- ret + theme(legend.key = element_blank())
  ret <- ret + theme(legend.position = "top")

  if (inherits(grid, "character") | grid == TRUE) {
    ret <- ret + theme(panel.grid = element_line(color = grid_col, size = 0.2))
    ret <- ret + theme(panel.grid.major = element_line(color = grid_col, size = 0.2))
    ret <- ret + theme(panel.grid.minor = element_line(color = grid_col, size = 0.15))

    if (inherits(grid, "character")) {
      if (regexpr("X", grid)[1] < 0) ret <- ret + theme(panel.grid.major.x = element_blank())
      if (regexpr("Y", grid)[1] < 0) ret <- ret + theme(panel.grid.major.y = element_blank())
      if (regexpr("x", grid)[1] < 0) ret <- ret + theme(panel.grid.minor.x = element_blank())
      if (regexpr("y", grid)[1] < 0) ret <- ret + theme(panel.grid.minor.y = element_blank())
    }
  } else {
    ret <- ret + theme(panel.grid = element_blank())
  }

  if (inherits(axis, "character") | axis == TRUE) {
    ret <- ret + theme(axis.line = element_line(color = "#2b2b2b", size = 0.15))
    if (inherits(axis, "character")) {
      axis <- tolower(axis)
      if (regexpr("x", axis)[1] < 0) {
        ret <- ret + theme(axis.line.x = element_blank())
      } else {
        ret <- ret + theme(axis.line.x = element_line(color = axis_col, size = 0.15))
      }
      if (regexpr("y", axis)[1] < 0) {
        ret <- ret + theme(axis.line.y = element_blank())
      } else {
        ret <- ret + theme(axis.line.y = element_line(color = axis_col, size = 0.15))
      }
    } else {
      ret <- ret + theme(axis.line.x = element_line(color = axis_col, size = 0.15))
      ret <- ret + theme(axis.line.y = element_line(color = axis_col, size = 0.15))
    }
  } else {
    ret <- ret + theme(axis.line = element_blank())
  }

  if (!ticks) {
    ret <- ret + theme(axis.ticks = element_blank())
    ret <- ret + theme(axis.ticks.x = element_blank())
    ret <- ret + theme(axis.ticks.y = element_blank())
  } else {
    ret <- ret + theme(axis.ticks = element_line(size = 0.15))
    ret <- ret + theme(axis.ticks.x = element_line(size = 0.15))
    ret <- ret + theme(axis.ticks.y = element_line(size = 0.15))
    ret <- ret + theme(axis.ticks.length = grid::unit(5, "pt"))
  }

  xj <- switch(tolower(substr(axis_title_just, 1, 1)),
    b = 0,
    l = 0,
    m = 0.5,
    c = 0.5,
    r = 1,
    t = 1
  )
  yj <- switch(tolower(substr(axis_title_just, 2, 2)),
    b = 0,
    l = 0,
    m = 0.5,
    c = 0.5,
    r = 1,
    t = 1
  )

  ret <- ret + theme(axis.text.x = element_text(size = axis_text_size, margin = margin(t = 0)))
  ret <- ret + theme(axis.text.y = element_text(size = axis_text_size, margin = margin(r = 0)))
  ret <- ret + theme(axis.title = element_text(size = axis_title_size, family = axis_title_family))
  ret <- ret + theme(axis.title.x = element_text(
    hjust = xj, size = axis_title_size,
    family = axis_title_family, face = axis_title_face
  ))
  ret <- ret + theme(axis.title.y = element_text(
    hjust = yj, size = axis_title_size,
    family = axis_title_family, face = axis_title_face
  ))
  ret <- ret + theme(axis.title.y.right = element_text(
    hjust = yj, size = axis_title_size, angle = 90,
    family = axis_title_family, face = axis_title_face
  ))
  ret <- ret + theme(strip.text = element_text(
    hjust = 0.5, size = strip_text_size,
    face = strip_text_face, family = strip_text_family
  ))
  ret <- ret + theme(panel.spacing = grid::unit(0.5, "lines"))
  ret <- ret + theme(plot.title = element_text(
    hjust = 0.5, size = plot_title_size,
    margin = margin(b = plot_title_margin),
    family = plot_title_family, face = plot_title_face
  ))
  ret <- ret + theme(plot.subtitle = element_text(
    hjust = 0, size = subtitle_size,
    margin = margin(b = subtitle_margin),
    family = subtitle_family, face = subtitle_face
  ))
  ret <- ret + theme(plot.caption = element_text(
    hjust = 1, size = caption_size,
    margin = margin(t = caption_margin),
    family = caption_family, face = caption_face
  ))
  ret <- ret + theme(plot.margin = plot_margin)

  ret <- ret + theme(panel.spacing = unit(0, "lines"))

  ret
}

# @title Pretty Colorbar
# @description Creates a wider, longer prettier colorbar for color or fill
# @examples
#' ggplot(mtcars, aes(mpg, wt, color = cyl)) +
#'   geom_point() +
#'   labs(
#'     x = "Fuel efficiency (mpg)", y = "Weight (tons)",
#'     title = "Seminal ggplot2 scatterplot example",
#'     subtitle = "A plot that is only useful for demonstration purposes",
#'     caption = "Brought to you by the letter 'g'"
#'   ) +
#'   pretty_bar() +
#'   theme_duncan()
# @export
# pretty_bar <- function(plot) {
#   if (length(unique(ggplot_build(plot)$data[[1]]["colour"]))) {
#     plot <- plot + ggplot2::guides(color = ggplot2::guide_colorbar(
#       title.position = "top", title.hjust = 0.5,
#       barwidth = unit(20, "lines"), barheight = unit(0.5, "lines")
#     ))
#   } else if (length(unique(ggplot_build(plot)$data[[1]]["fill"])) >= 2) {
#     plot <- plot + ggplot2::guides(fill = ggplot2::guide_colorbar(
#       title.position = "top", title.hjust = 0.5,
#       barwidth = unit(20, "lines"), barheight = unit(0.5, "lines")
#     ))
#   }
# }

#' Update matching font defaults for text geoms
#'
#' Updates [ggplot2::geom_label] and [ggplot2::geom_text] font defaults
#'
#' @param family,face,size,color font family name, face, size and color
#' @export
update_geom_font_defaults <- function(family = "Open Sans", face = "plain", size = 3.5,
                                      color = "#2b2b2b") {
  update_geom_defaults("text", list(family = family, face = face, size = size, color = color))
  update_geom_defaults("label", list(family = family, face = face, size = size, color = color))
}

#' @rdname OpenSans
#' @md
#' @title Open Sans font name R variable aliases
#' @description `font_on` == "`Open Sans`"
#' @format length 1 character vector
#' @export
font_os <- "Open Sans"

#' @rdname FiraSans
#' @md
#' @title Fira Sans font name R variable aliases
#' @description `font_fn` == "`Fira Sans`"
#' @format length 1 character vector
#' @export
font_fs <- "Fira Sans"