cairo_pdf("cairo-faces.pdf", width=4.5, height=.5)
grid.rect(gp=gpar(col="grey"))
grid.text("hello", x=1/5, 
          gp=gpar(fontfamily="Ubuntu"))
grid.text("hello", x=2/5, 
          gp=gpar(fontfamily="Ubuntu", fontface="bold"))
grid.text("hello", x=3/5, 
          gp=gpar(fontfamily="Ubuntu", fontface="italic"))
grid.text("hello", x=4/5, 
          gp=gpar(fontfamily="Ubuntu Condensed"))
dev.off()