Customize Contour Labels in ggplot2 - r

Question

I'm relatively new to ggplot2, and I'm having trouble adding appropriate labels to my contours. I would love to be able to add the labels without the directlabels package, but I haven't found a way to, so if you know of a way to customize labels without directlabels, I would love to here it.
Using the classic volcano example, I can add labels to the default contour plot using the directlabels packet in the following way:
library(plyr)
library(ggplot2)
library(directlabels)
library(reshape)
volcano<-melt(volcano)
v<-ggplot(volcano, aes(x,y,z=z))
e<-v + stat_contour(aes(colour=..level..))
direct.label(e)
In the above example, the labels are added appropriately, but things become more complicated if I try to specify my own break points for the contours:
e<-v + stat_contour(aes(breaks=c(160, 170, 180), colour=..level..))
direct.label(e)
Now, the contours are specified by the breaks I have provided, but labels still appear for all of the default contours. How do I only plot only labels for the graphed contours?
A related issue, how would I plot labels for contour levels not included in the default? Say a break of 165:
e<-v + stat_contour(aes(breaks=c(165), colour=..level..))
direct.label(e)
Thanks for any help!

Answer 1

The current development version (directlabels_2013.6.15 with ggplot2_0.9.3.1) should fix your problem (as the author of the directlabels package explained to me). You can install it with:
install.packages("directlabels", repos="http://r-forge.r-project.org")
And then:
library(plyr)
library(ggplot2)
library(directlabels)
library(reshape)
volcano<-melt(volcano)
v<-ggplot(volcano, aes(X1,X2,z=value))
e<-v + stat_contour(aes(colour=..level..), breaks=c(165))
direct.label(e)
I noted several other limitations with simple workarounds:
the first ggplot call must contain the z aesthetic
this works only with the stat_contour (and not with the geom_contour)
the colour aesthetic must be defined in the stat_contour call and set to ..level..
Finally, if you want to control the label and contour line colours (black labels and blue contour lines for instance), you can achieved this as follow:
e<-v + stat_contour(aes(colour=..level..), colour = "blue", breaks=c(165))
e<-e + scale_colour_continuous(low = "#FF0000", high = "#FF0000")
direct.label(e)