In article <403### [at] univ-savoiefr> , Christophe Raffalli 
<raf### [at] univ-savoiefr>  wrote:

> But how ? It is nowwhere in the doc ?
>
> Lets say you have a triangle <A,B,C>.
>
> If the normal defining tre front face the vertor product of (B-A) and (C
> -A) ? Is it somthing else ?

To solve your problem, it does not matter which order is used.  All that
matters is that the same order is always used, which obviously is the case
in a computer program.  From there it is really easy to determine which
order defines the frontface and the backface, as there are only exactly two
combinations possible as a triangle has exactly two sides.  So it is
extremely easy to find out by just applying a backface and frontface texture
even if this is not defined in the documentation (I did not search if it
is).  All you have to do is to always supply your vertices in the same
order.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

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