您可以使用coord_map
ggplot 的参数记录在这里 http://docs.ggplot2.org/current/coord_map.html
这使用投影来改变坐标网格。曲线将包括等距离投影,但你应该看看here http://www.inside-r.org/packages/cran/mapproj/docs/mapproject获取所有允许的投影的列表。您选择哪一个是一种偏好。
Using azequidistant
(我认为这是方位等距投影 https://en.wikipedia.org/wiki/Azimuthal_equidistant_projection),并手动添加标签:
axis_labels <- rbind(
data.frame(long = rep(-140,5),lat = seq(40,80,10), labels = seq(40,80,10)), # x axis labels
data.frame(long = seq(-140,-60,40),lat = rep(85,3), labels = seq(140,60,-40)) # y axis labels
)
ggplot() +
geom_polygon(data=countries,aes(x=long,y=lat,group=group),fill='white',color = "black") +
coord_map("azequidistant") +
scale_x_continuous(breaks = seq(-140,60, by = 20))+
scale_y_continuous(breaks = seq(40,80, by = 10)) +
geom_text(data = axis_labels, aes(x = long, y = lat, label = labels)) +
theme_bw() +
theme(panel.grid.major = element_line(colour = "grey"),
panel.border = element_blank(),
axis.text = element_blank())