Make a solid black (r0,b0,g0) 64x64 texture with single pixels of whatever color you want the tint to be... this is a crappy example, but just to get the idea....
then you select all the faces that you want to be tinted and open up binmapper. select all the vertice points in the mapper and push them all together in a corner until thay all are on top of each other (one point). then move that group next to any of the colored pixels and press ok to finish mapping. that's it.
you can also create L or U shapes with the colored pixels on the texture to create a darker tint by covering more than one side of the vertice group.
and.. you can layer faces on top/behind each other with different colors to create different shades/effects.
one thing to keep in mind is these tranparent faces must be added last to your model or everything behind them will appear transparent as well.
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>>>Can the technique be used to make realistic windows in trucks?
yes, I've done an entire truck body and it worked, except in some camera angles portions of the interior were rendered invisible.
I've probably made 50 trucks in the past several weeks that I never uploaded lol, I just play around with things to see what works and what doesn't then toss em in the trash can.
(I may release my forklift tho if someone ever finshes the warehouse lol)
it was neat - it looked like an animated model on a truck