tm_shape(World)


tm_shape(World) +  tm_fill("pop_est_dens", fill.scale = tm_scale_intervals(c("yellow", "orange", "red"))) + tm_facets(by = "continent")

tm_shape(World) +  tm_fill("pop_est_dens",
fill.scale = tm_scale_intervals(c("yellow", "orange", "red"))) + tm_facets(by = "continent")