R plot filled.contour() output in ggpplot2

Question

I want to plot this figure created with filled.contour(), but in ggplot2, how do I do this?

I want to use ggplot2 because the graphing conventions are easier. The r

Answer 1

To follow up on @hrbrmstr's minimal example, you can also have ggplot2 compute "z" for you:

library(ggplot2)
ggplot(data = faithful, aes(x = eruptions, y = waiting)) +
  stat_density2d(aes(colour = ..level.., fill = ..level..), geom = "polygon")