r - ggmap stamen map accuracy glitch -

r - ggmap stamen map accuracy glitch -

ggmap appears handling map tiles google , stamen inconsistently, @ to the lowest degree @ global scale. stamen problem. next code illustrates.

require(ggplot2); require(ggmap) m_google = get_map(location = c(-.2, 51.5), zoom=3) m_stamen = get_map(location = c(-.2, 51.5), zoom=3, source = "stamen", maptype = "toner") ggmap(m_google, extent = 'panel') + geom_point(data=null, aes(-.2, 51.5), col='red', size=5) ggmap(m_stamen, extent = 'panel') + geom_point(data=null, aes(-.2, 51.5), col='red', size=5)

glitch?

r ggmap