I'm currently creating plots in ggplot2 by importing custom images and using them as geom_points, similar to this post, except I am looping through different images for unique levels of a factor.
Is there an easy way to add these images to the legend? I've seen multiple posts on custom legends in ggplot2, but nothing that deals with imported images.
Using html tags with element_markdown, you can specify anything you want in your legend.
Assuming that you have a png image in a file, that this file is located in a certain folder having a filename image, then you can run, for example:
p = ggplot(mtcars, aes(mpg, disp, colour = factor(vs))) +
geom_point() +
theme(legend.key.size = unit(1, "cm"))
labels <- c()
labels[1]=paste0("<img src='", folder, image, ".png' width='16' />")
labels[2]="<strong>Faces</strong>"
p + theme(legend.text = element_markdown(color = "black", size = 11)) +
scale_color_manual(name = "factor(vs)", labels = labels, , values = c(1,2))
will return this:
