library(silicate)
x <- rnaturalearth::countries110[9, ]
a <- SC(x)
library(RTriangle)
ps <- RTriangle::pslg(P = as.matrix(a$vertex[c("x_", "y_")]), S = cbind(match(a$edge$.vertex0, a$vertex$vertex_), match(a$edge$.vertex1, a$vertex$vertex_)))
b <- RTriangle::triangulate(ps)
V <- b$VE;  V <- V[V[,1] > 0 & V[,2] > 0, ]
plot(ps, pch = ".", asp = 1)
segments(b$VP[V[,1],1], b$VP[V[,1],2], b$VP[V[,2],1], b$VP[V[,2],2], col = "firebrick")