Plot intersecting areas

Ever had to plot intersecting areas?
From now on I would use rgeos to do similar things. The following does the trick:

library(rgeos)
library(DescTools)

Canvas(, xpd=TRUE)
p1 <- as(DrawCircle(0.5)[[1]], "gpc.poly")
p2 <- as(DrawCircle(-0.5,0.5)[[1]], "gpc.poly")
p3 <- as(DrawCircle(0,-0.5)[[1]], "gpc.poly")
plot(append.poly(append.poly(p1, p2), p3), axes=FALSE, frame.plot=FALSE, xlab="", ylab="")
plot(intersect(p1, p2), poly.args = list(col = "red"), add = TRUE)
plot(intersect(intersect(p1, p2), p3), poly.args = list(col = "blue"), add = TRUE)