In get_googlemap, zoom argument overrides visible argument

[birdnirdfoley]

In get_googlemap(), using the visible argument as a replacement for zoom doesn't work, since zoom is required to be numeric, the default is set to zoom = 10, and zoom is always pasted into the url. (The replacement of zoom with visible is discussed in this Google Maps Static Maps help article).

library(ggmap)
ggmap(get_googlemap(center = c(-75.90625, 37.9375), 
                    maptype = "satellite", color = "color", 
                    visible = data.frame(longitude = c(-75.93750,-75.87500), 
                                        latitude = c(37.95833,37.91667))))

This will use the default zoom = 10, not the smaller visible argument that is provided:

If the url is pasted into a browser and "zoom=10&" is deleted from the url, the updated map shows the desired extent.

The visible argument allows more precise fine-tuning, and includes the attribution information (there is also the known issue of non-square sizes being improperly displayed, making the size argument potentially problematic). Using the size parameter to resize the extent removes much of the attribution, eg:

library(ggmap)
ggmap(get_googlemap(center = c(-75.90625, 37.9375), 
                    maptype = "satellite", color = "color",
                    zoom = 13, size = c(450, 450)))