Okay, I'm jumping in. I must admit at first I thought the way you did:
setting the normals would override the whole CCW computation of object
culling. After doing some research in my OpenGL "redbook", I found that
I was wrong.
In OpenGL, you can only specify normals at the vertex level, but that
normal is not used for culling purposes. *Only* the ordering of the
vertices and the current "front facing mode" (can be set to CCW or CW)
determines the front face for culling.
Final Answer: yep, you're stuck having to specify vertices in CCW
order. I do agree that I really couldn't find this tidbit in the API.
BTW, the reason I talk about OpenGL so much is that Java3D can't do
something that OpenGL doesn't allow. Also, I don't know jack about
DirectX. :)
-Lee
> -----Original Message-----
> From: Justin Couch [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, April 18, 2001 10:33 AM
> To: [EMAIL PROTECTED]
> Subject: Re: [JAVA3D] Lighting/Normals problem
>
>
> Alf Edgar Andresen wrote:
>
> > > anywhere. If so, it must be another one of these magic
> things that we
> > > don't really need to know about and therefore is not
> worth documenting.
> >
> > OpenGL-standard, I think.
>
> Well, putting on my Newbie hat as these are the sorts of
> questions I get
> asked:
>
> - I downloaded and installed the DirectX version. What has that got to
> do with OpenGL?
>
> - The documentation does not say that I must declare my
> vertex lists in
> ccw order so it's a bug in the API.
>
> - I provided normals and so the application must use those to
> calculate
> which way a face is pointing. If not, what is the point of supplying
> normals?
>
> Also, look at the other response about having to deal with unknown
> content coming in and not knowing whether to unwind or not.
>
> --
> Justin Couch http://www.vlc.com.au/~justin/
> Freelance Java Consultant http://www.yumetech.com/
> Author, Java 3D FAQ Maintainer http://www.j3d.org/
> -------------------------------------------------------------------
> "Humanism is dead. Animals think, feel; so do machines now.
> Neither man nor woman is the measure of all things. Every organism
> processes data according to its domain, its environment; you, with
> all your brains, would be useless in a mouse's universe..."
> - Greg Bear, Slant
> -------------------------------------------------------------------
>
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