How to create outlines around edges

[patrickroykirkby]

Hi everyone, I'm trying to render a UV template with white highlights around certain edges of this rock that I have created. In the first image you can see my UV map, the 2nd image is just my rock, and the 3rd image I put an ink and paint material on it and rendered it.

I don't want to use the ink and paint material in the end, but I do want to paint those highlights on manually. However, since I'm making lots of rocks, I want to find a quicker process. When I render the UV template, it has all those white lines around each polygon, but I don't want that many outlines.

I would love to find a way to render the material or extract it somehow with white outlines only around specific edges, similar to the way the ink and paint material renders. Then I will know my edges and would be able to paint them as I see fit in photoshop. Thanks in advance!

[RobH2]

There's probably a better way but what if you 'detach' the specific parts that you want to have isolated for painting? UV those as separate elements of the whole rock. Link the parts together so when you move the main rock everything follows. It's still going to take some time. I can't think of something that's automatic or faster. 

[patrickroykirkby · Accepted solution]

I ended up doing something similar, I just highlighted the faces of each flat section of the rock, then in photoshop I outlined the rendered template area. It's tedious but ended up with a desired result. Thanks for your time!