What is meant by the 'duplicate and invert geometry method'?

written by piraniac in his toon shader demo file.

How would you use that to create the toon look?

Thanks much for any info on this…

I just was thinking it would be fun to have just one little toon. Maybe…

‘duplicate and invert geometry method’ it’s probably not a shader, but the
old trick to made a dark outline in you character…if I understood well…

It refers to when you duplicate your mesh, enlarge it (typically using shrink/fatten), then recalculate the normals inside (CTRL+SHIFT+N), then color the copy black. This creates the illusion of a black outline around your model.

Use it with caution though–it also duplicates the polycount of your model!

ahoh… I get it, thanks very much.