Consistent exported font sizes

consistent_fontsize.R

# Only needed if using theme_cowplot. Otherwise, use any theme. 
library(cowplot)

theme_cowplot_consistent_text <- function (font_size = 8) {
  
  theme_cowplot() %+replace%
       theme(strip.text = element_text(size = font_size),
             axis.text = element_text(colour = "black", size = font_size),
             plot.title = element_text(size = font_size),
             axis.title = element_text(size = font_size),
             legend.text = element_text(size = font_size),
             legend.title = element_text(size = font_size),
             legend.key.size = unit(0.5, "lines"),
             axis.title.x = element_text(margin = ggplot2::margin(t = 0, r = 0, b = 0, l = 0), vjust = 1),
             axis.text.x = element_text(margin = ggplot2::margin(t = 1, r = 0, b = 0, l = 0), vjust = 1),
             axis.title.y = element_text(margin = ggplot2::margin(t = 0, r = 0, b = 0, l = 0), angle = 90, vjust = 1),
             axis.text.y = element_text(margin = ggplot2::margin(t = 0, r = 1, b = 0, l = 0), hjust = 1)
            )
  
}

theme_set(theme_cowplot_consistent_text(font_size = 8))

This is the theme I use to get all pdf images exported with ggsave to have font size 8 for all text elements in the plot.

The theme doesn't seem to carry through to ggrepel, so use geom_text_repel(size = 2.5) to get about size 8 font. (size = 2 for about 6 pt).

Font will be size eight when exported as in:
plt %>% ggsave("figures/plot.pdf", ., device = "pdf", width = 3, height = 1.75, units = "in")

To load it do:
library(cowplot)
theme_set(theme_cowplot_consistent_font(size = 8))