Apply the RO ggplot2 theme and auto-fix common RO style requirements

ro_gg_plot() is a concept/draft function that explores applying the RO visual style in a single step, instead of requiring the separate calls to ro_gg_theme(), ro_gg_remove_axis_gap(), ro_gg_axis(), a manual thousands-separator, ro_gg_group_ticks(), and ro_gg_y_title() described in the vignette("ggplot2-in-ro-style") vignette.

Unlike ro_gg_theme(), which returns a theme() object that only carries cosmetic settings, ro_gg_plot() takes the whole plot as input and returns a modified plot. This is required because several RO style rules (axis limits/expansion, number formatting, y-axis title position) depend on the data, the scales, and the geoms already present on the plot, none of which a plain theme() object can see. Call ro_gg_plot() last, after all layers, scales, and labels have been added.

Usage

ro_gg_plot(
  plot,
  flip = FALSE,
  base_size = 12,
  base_family = "RijksoverheidSansWebText",
  lang = c("nl", "en"),
  auto_set_y_title = TRUE
)

Arguments

plot: A ggplot object, with all layers, scales, and labels already added.
flip: Logical. Passed on to ro_gg_theme(). Default = FALSE.
base_size: Integer. Passed on to ro_gg_theme(). Default = 12.
base_family: Character. Passed on to ro_gg_theme(). Default = "RijksoverheidSansWebText".
lang: Character. "nl" (default) uses a dot as thousands separator (e.g. "1.000"); "en" uses a comma (e.g. "1,000").
auto_set_y_title: Logical. If TRUE (default), relocates the y-axis title via ro_gg_y_title(), as described above. Set to FALSE to leave the y-axis title alone (ro_gg_plot() then only applies the cosmetic theme, legend, and axis changes) so you can position it yourself, e.g. with your own ggplot2::annotation_custom() call, or via theme(axis.title.y = ...) if the default placement isn't needed at all.

Value

A modified ggplot object.

What this does automatically

Applies the ro_gg_theme() cosmetic theme.
Removes legend titles (RO style never shows one), for fill, colour/color, shape, linetype, alpha, and size.
For bar/column charts (any layer using geom_col()/geom_bar()), sets the group width to 80% of each category slot, removes any padding between bars within the same group (switching position_dodge2() to position_dodge() if needed), and removes bar outlines. Tick marks are then moved from under each category to the boundary between groups via ro_gg_group_ticks(). Works for both the default and flipped (flip = TRUE) orientation.
For bar/column and line charts (any layer using geom_col()/geom_bar()/geom_line()), and only if the user has not already added a scale for the continuous axis, applies ro_gg_remove_axis_gap() expansion, ro_gg_axis() as the axis limits (so the continuous axis starts at 0), and a thousands separator on the labels. Other chart types (e.g. scatter plots) only get the thousands separator.
Relocates the y-axis title to the RO position via ro_gg_y_title(), when a y-axis title is present. Works for both the default and flipped (flip = TRUE) orientation.

Known limitations

The bar group width (80%), zero padding within a group, and tick-mark styling (color/width/length) are fixed and not user-configurable; if you need different values, apply ro_gg_group_ticks() and the geom parameters yourself instead of ro_gg_plot().
Detecting whether a scale was already set by the user relies on plot$scales$scales, which is a bit buggy.
Facetted plots are not specifically handled; ro_gg_y_title() and ro_gg_group_ticks() only look at the first panel.

Examples

if (FALSE) { # \dontrun{
library(ggplot2)

dat <- data.frame(
  agegroup = c("0-19", "20-39", "40-59"),
  n = c(1200, 4800, 6100)
)

p <- ggplot(dat, aes(x = agegroup, y = n)) +
  geom_col() +
  labs(title = "Cases by age group", y = "Number of cases", x = "Age group")

# build the plot fully with `+` first, then call ro_gg_plot() on the finished object
ro_gg_plot(p)
} # }