Google Chart Overlays using googleVis package in R

问题

Google Charts has overlay functionality that allows you to put an image over a plot at a specified position. Is this possible in the googleVis package or do I need to edit the chart html ad hoc to include an overlay?

回答1:

You can add an overlay to a Google map using my googleway package. To use Google Maps you need a valid API key

library(googleway)
map_key <- 'your_api_key'

google_map(key = map_key) %>%
    add_overlay(north = 40.773941,south = 40.712216, east = -74.12544, west = -74.22655,
                            overlay_url = "https://www.lib.utexas.edu/maps/historical/newark_nj_1922.jpg")

来源：https://stackoverflow.com/questions/37758585/google-chart-overlays-using-googlevis-package-in-r