well, that's a bit old thing I wanted to post, I reminded it now thanks to aldo's post, btw I think that many here could find it useful
without smoothgroups
with smoothgroups
this is a mix of smooth and faceted shadings converted with cob2fs2, but you can obtain similar results using PCS and different autofaceted angles.
Why smoothgroups? (I hope you'll understand this despite my english)
smooth shadings are intended to simulate roundness.
Using autofacet you'll apply the smooth only to the gruop of faces with an angle lower than a defined degree to each other (well actually it depend by normals, and I still have to understand if it just affect the amount of roundness or if it dinamically select what faces to smooth and what not depending by the angle).
This means (in theory) that with a smoothing angle lower than 90° a cube will remain a cube with the shadings of a cube and not of a sphere..with autofacet you'll obtain better results than with smooth when generically applyed to the whole model.
Unfourtunately there are many situations where either smooth shadings and autofacet generate weird shadings. This depend usually by the hard edges connected to rounded parts, like in the example I made above.
How to solve this?
in two ways: splitting meshes or using autofacet
splitting the mesh mean to just cut the offending detail and have it as a submodel. All the rounded polys will stay together, without hard edges. Obviously this isn't very efficent in a game model, and it's stupid anyway if you can use smoothgroups.
Smoothgroups mean to give different shadings to different groups of polys. All the connected faces sharing the same shadings (type or angle) will stay together like if they're indipendent, the hard edges will not affect them and the smooth shadings will be as clean as possible.
To make smoothgroups in Truespace:
open the textured model
open the material editor
select a group of faces whith the same texture that you want to use the same shadings
select their texture and the type/angle of shading you want to use and press the paint tool: all those faces will be painted with the selected texture and will be a smoothgroup.
Remember to don't use the same type/angle of shading of the neighbor faces
that's it