ggplot2 multiline title, different indentations

Question

I am generating graphs for a publication and I\'d like to be able to label the panels of a figure in ggplot itself (as opposed to exporting to publisher, etc) so that they j

Answer 1

You can do this by manipulating Grobs. Using gtable and grid on top of ggplot2.

library("ggplot2")
library("gtable")
library("grid")

p <- ggplot(iris, aes(x = Sepal.Length, y = Sepal.Width, color = Species, shape = Species))+
  geom_jitter(size = 6.5)+
  ggtitle("The Actual Long, Normal Title of Titliness")+
  theme(plot.title = element_text(hjust = 0.5, face = "bold", size = 30),
        axis.ticks = element_blank(),
        legend.text = element_text(size = 25),
        axis.title = element_text(size = 25, face = "bold"),
        axis.text = element_text(size = 25, vjust = 0.05),
        legend.position = "bottom",
        plot.margin = unit(c(4, 1, 1, 4), "lines"))  # We need bigger top/left margins to show the letter

gt <- ggplot_gtable(ggplot_build(p))  # Building a gtable from the ggplot object
# Adding the textGrob for the panel letter
panel_letter = textGrob("A", x = 0.5, y = .9, 
                        just = c("left", "top"), 
                        gp = gpar(fontsize = 40, col =  "black", face="bold"))
gt <- gtable_add_grob(gt, panel_letter, t=1, l=1, r=1)  # Append the Grob to the table

p <- grid.draw(gt)  # Display the plot
ggsave("plot.png",gt, width=10, height=10)  # If you want to save it.