In article <eric.medlin-37D475.12283223032004@news.povray.org> , Eric Medlin
<eri### [at] ipapercom>  wrote:

>> UV-mapping is a modifier that applies to the normal statement, as explained
>> in the manual.  The fact that it is set directly in front of the
>> image-pattern implies nothing.  It still applies to the normal statement,
>> not the image-pattern statement!  This is exactly like all modifiers in
>> POV-Ray work.
>
> I also thought it was applying it to the normal statement only, but it
> is applying it to the image pattern statement also.  In my example I
> used two normals statments one for below 0.5 and one for above 0.5.
> When uv mapping is applied you can clearly see that the image pattern is
> being uv mapped.  It is probly applying it to the normals to though
> causing the scaling.  Either way I don't see where it says it will apply
> it to both.

You are not understanding at all what an image-pattern does!  It does only
define a pattern of the image in the unit cube.  The pattern (the checker
pattern makes this easy to see) together with the normal map is part of the
the surface normal function, and that is then mapped onto the surface (this
is what the uv-mapping modifier specifies) using uv-mapping, which is a
2d-function, rather than specifying 3d-function.  This is exactly like it
works for every pattern and every other statement using patterns in POV-Ray.
In fact, it would not make any sense to just pick arbitrary parts of the
normal statement and use only them for uv-mapping.

Just imagine what would happen if what you seem to be expecting was the case
when using pigments.  The image-map would be uv-mapped and a pigment-map
would not? - This could never work in a predictable manner at all!

    Thorsten

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

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