OK everyone, here's a tuff little cookie for you...

How do you make something *look* reflective? How do you make something
*look* transparent?

Of course, making something reflective is easy - just add the appropreate
block to the texture statement. But that doesn't necessarily make the object
*look* reflective... For example, take a shiny white sphere, and add a
reflection statement. Since there is nothing else in the scene, the
resulting image is identical. The sphere IS reflective, but still doesn't
LOOK reflective. Ditto for refraction.

Now, I find that if the surfaces in question are curved, animating the scene
so that the surface itself or something else in the scene moves immediately
gives the desired effect. But how do you make objects in still images look
right?

Don't get me wrong - I have managed to do it before now. I'm just asking if
anyone out there has any specific tips on how to do this. (Aside from the
obviouse "have something else in the scene to reflect/refract"!)

What kinds of things make for good reflections/refractions? Checkered floors
tend to emphasise the curved nature of non-flat surfaces, but the image can
get rather "busy" and confusing to look at. Stone-like or shy-like textures
seem to work better, but I still have trouble finding good colours.

In particular, the reflections/refractions can make an object look the wrong
colour - that is, sometimes it looks like the object itself is coloured and
the image being reflected in black and white... Is there a general answer
these sorts of questions, or is it just a case of fiddling for hours until
it looks right?

OK, well, let's see what people can come up with...

Thanks.
Andrew.

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Andrew Coppin wrote:

>How do you make something *look* reflective? How do you make something
>*look* transparent?
>
>Of course, making something reflective is easy - just add the appropreate
>block to the texture statement. But that doesn't necessarily make the object
>*look* reflective... For example, take a shiny white sphere, and add a
>reflection statement. Since there is nothing else in the scene, the
>resulting image is identical. The sphere IS reflective, but still doesn't
>LOOK reflective. Ditto for refraction.
>

Well, as you said, a lot of it depends on whats in the scene. But what I
often do when I'm testing a scene so not all the objects are there yet, or
when I don't want a slooow reflection making my test render needlessly
long, is give it a low reflection value and a high specular value. This
shows off contours and highlights, gives me some idea of how reflection and
lighting are playing with the surface, but renders quickly and looks
acceptable. (Sometimes good enough that I forget to change it in the
final...)

RG - if Microsoft had invented senility, it wouldn't be a problem, it would
be a feature

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gonzo <rgo### [at] lansetcom> wrote in message news:web.3e18ca874b2
> Well, as you said, a lot of it depends on whats in the scene. But what I
> often do when I'm testing a scene so not all the objects are there yet, or
> when I don't want a slooow reflection making my test render needlessly
> long, is give it a low reflection value and a high specular value. This
> shows off contours and highlights, gives me some idea of how reflection
and
> lighting are playing with the surface, but renders quickly and looks
> acceptable. (Sometimes good enough that I forget to change it in the
> final...)
>
> RG - if Microsoft had invented senility, it wouldn't be a problem, it
would
> be a feature
>

I agree with gonzo that specular helps with this some. It gives it a
polished look sort of, instead of a reflective look. like a black polished
shoe, it doesnt relfect (atleast mine dont) but it still has some quality
about it that makes you think its shiney. If i have an object that i think
might be shiney or reflective i start with a specular of 0.35

as for making something look transparent without making it transparent? i
dont know anything about that :)



ross

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"Ross Litscher" <lit### [at] osuedu> wrote in message
news:3e1b7cb6@news.povray.org...
>

> as for making something look transparent without making it transparent? i
> dont know anything about that :)

You could use the old theatre-trick of reflecting it in a sheet of glass, and
only viewing the reflection.

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"Tom Melly" <tom### [at] tomandlucouk> wrote in message
news:3e1ef35f$1@news.povray.org...
>
> You could use the old theatre-trick of reflecting it in a sheet of glass, and
> only viewing the reflection.

... which might be a useful general trick to avoid slow merges or artifacts in,
for example, poser meshes*

* I was thinking of modelling the Fantastic Four, and considered doing this for
the invisible woman

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Tom Melly wrote:
<snip>
>* I was thinking of modelling the Fantastic Four, and considered doing this for
>the invisible woman
>

I can't see that

:-)

John
--

Run Fast
Run Free
Run Linux

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>>
>> You could use the old theatre-trick of reflecting it in a sheet of glass, and
>> only viewing the reflection.
>
This would have the drawback of also reflecting other lights in the scene,
although a light group would probably solve that.

>
>* I was thinking of modelling the Fantastic Four, and considered doing this for
>the invisible woman
>

I think the specular trick would work very well here. Make her completely
transparent, but set the specularity high enough to highlight facial
features and such (.3 - .5). In a light group this would give you a great
deal of control. You probably don't want reflection in this case.

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