I've been working with Google sketchup to create triangulated 3D models that I wanted to render in Processing.  I thought I would share a short list of c shell commands I wrote to do the conversion automatically.  The following list of commands take an obj file (input.obj) and covert it to a list of processing vertices (output.txt).  I've only tested this with OBJ files exported from sketchup (select the "all faces triangulated" and "swap YZ" options for exporting).

1. awk '/v /' input.obj | awk '{print "vertex (",$2,",",$3,",",$4,");"}' > temp1.txt
   awk '/f /' input.obj | tr '/' ' ' | awk '{print $2,"\n",$5,"\n",$8}' | awk '/[0-9]/ {print "sed -n ",$1," p temp1.txt"}' | sed "s/n  /n '/" | sed "s/  p/'p/" | sh > output.txt
   rm temp1.txt
   

I'm not sure how this code will render, but there should only be three lines, two beginning with an awk command and the third an rm command.
Someday I will learn a real scripting language.