This make it (theoriticaly) compatible with all supported hardware with
consistent results.
Also we now draw the lines with analytic anti-aliasing instead of relying
on MSAA (which offers less benefits in our case).
The remaining aliasing comes from edges cut in half by the mesh which is
not rendered with MSAA. Hopefully this is not too much distracting and only
happen if the face is almost parallel to the view.
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