well the look in that clip is not that hard to do actually, it’s a quite simple outline and most of the work is done at the shader level, the trick is always to have a line on separate layer to be able to do masking.
Lines are getting hard to managed in mental ray in Maya once you have to do something other that a simple outline, like line only at specifics place, lines that should get thiner at other place, lines with noise etc…the workflow in mental ray is actually the worst you can imagine, having to deal with shader contrast, shader store and what’s not…I hate it it’s totally worthless and I’d like to punch the developper who though it was artist friendly.
Anyway line is always a bunch of tips and trick, but if you want a simple outline that is clean around a character, then yes mental ray contrast works good, just make sure you put enough sample 12-20 should do it.
I’ve been doing toon for over a decade and not much have evolve in that sense.
Maya Toon is actually quite cool, but unfortunatly is quite hard also to get nice line with eavy model, because it work only on non smooth object, or you have to subdivide your model manually and sample the line quite a lot which gets really heavy for maya.
To have a nice line where you want, you sometime have to have a model exclusively for the line with the hard edge where you want the line etc… it’s awfull to do it that way but it’s often the best solution.