[R] ggplot2 - getting at the grobs

[Pedro de Barros]

Dear All,

I continue trying to get several of my plotting functions to use 
ggplot, because I really do like the concept of the graphical 
objects, and working with them in the abstract.
I am now trying to access the grobs to manipulate using grid. 
However, until now all I managed was to get the plot as a gTree 
object, and manipulate it as a gTree from there. The problem is that 
then it is no longer a ggplot, and thus I can no longer use the 
ggplot functions.
How to get at the grobs, without converting the ggplot into a gTree?

Thanks,
Pedro