Does anyone know how to control the color of a specular highlight?  Ie, I
want the color of a material to be, say, rgb 1, but the highlight to be rgb
<1,0,0>.  I've tried using light groups, but if I use a second light source
of a different color for the highlight, then it affects the base color of
the object as well.

Any thoughts?

...Chambers

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"Ben Chambers" <bdc### [at] hotmailcom> wrote in message
news:3bce0910$1@news.povray.org...
> Does anyone know how to control the color of a specular highlight?  Ie, I
> want the color of a material to be, say, rgb 1, but the highlight to be
rgb
> <1,0,0>.  I've tried using light groups, but if I use a second light
source
> of a different color for the highlight, then it affects the base color of
> the object as well.
>
> Any thoughts?

Only way I know of is to put a underlayer texture which is highly specular
and metallic (and red) with the upper layer being highlightless and slightly
transparent but not enough to show.  Checking on it I could get a decent red
highlight using rgbt<1,1,1,0.01> for the top layer and specular 50 to 100
for the bottom layer.

Bob H.

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maybe try 'metallic' keyword.

-tgq


"Bob H." <omn### [at] msncom> wrote in message
news:3bce132c@news.povray.org...
> "Ben Chambers" <bdc### [at] hotmailcom> wrote in message
> news:3bce0910$1@news.povray.org...
> > Does anyone know how to control the color of a specular highlight?  Ie,
I
> > want the color of a material to be, say, rgb 1, but the highlight to be
> rgb
> > <1,0,0>.  I've tried using light groups, but if I use a second light
> source
> > of a different color for the highlight, then it affects the base color
of
> > the object as well.
> >
> > Any thoughts?
>
> Only way I know of is to put a underlayer texture which is highly specular
> and metallic (and red) with the upper layer being highlightless and
slightly
> transparent but not enough to show.  Checking on it I could get a decent
red
> highlight using rgbt<1,1,1,0.01> for the top layer and specular 50 to 100
> for the bottom layer.
>
> Bob H.
>
>
>

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Well I was checking that out some more and the white texture really washes
it out so it might not have been a good idea after all.
Being able to light_group textures alone instead of objects would be of
great use for this sort of thing.

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"Ben Chambers" <bdc### [at] hotmailcom> wrote in message
news:3bce0910$1@news.povray.org...
> Does anyone know how to control the color of a specular highlight?  Ie, I
> want the color of a material to be, say, rgb 1, but the highlight to be rgb
> <1,0,0>.  I've tried using light groups, but if I use a second light source
> of a different color for the highlight, then it affects the base color of
> the object as well.
>
> Any thoughts?
>

Sounds tricky, in that, as far as I can tell, you're trying to model very
unrealistic behaviour...

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"Tom Melly" <tom### [at] tomandlucouk> wrote in message
news:3bcec198@news.povray.org...
> "Ben Chambers" <bdc### [at] hotmailcom> wrote in message
> news:3bce0910$1@news.povray.org...
> > Does anyone know how to control the color of a specular highlight?  Ie,
I
> > want the color of a material to be, say, rgb 1, but the highlight to be
rgb
> > <1,0,0>.  I've tried using light groups, but if I use a second light
source
> > of a different color for the highlight, then it affects the base color
of
> > the object as well.
> >
> > Any thoughts?
> >
>
> Sounds tricky, in that, as far as I can tell, you're trying to model very
> unrealistic behaviour...

So?  And a reflective sphere really -does- float above a checkered plane? :)

Actually, I -would- just use reflection min and max to give my object a
colored tint, but that then depends on the surroundings for the color.  I'd
rather have it based on the surrounding -lights- than the
surrounding -objects-.

...Chambers

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"Ben Chambers" wrote:
> Does anyone know how to control the color of a specular highlight?

Yes, the following workaround is tested and works. (I used it for my Compact
Disc Include File, which can be found on my website.)

Use a texture_map with an average pattern to average two textures. One of
the textures is whatever texture you want. The other is a texture with just
a highlight.

The texture with the highlight should have a pigment with the color that you
want the highlight to be. Use metallic for the highlight. Use ambient 0 and
diffuse 0.

The other texture can be practically anything you want.

If you don't specify any weights for the two textures in the average, they
will both have a weight of 0.5. That means that you need to multiply
practically all the values in the finish statement (ambient, diffuse,
reflection, specular etc.) with 2. In both textures that is.

You can probably also specify a weight of 1 for the highlight texture and a
weight of 10000 for the other texture; then you only need to remember to
multiply the highlight by 10000, but the other texture you can leave alone.
That's probably easier, but I haven't tested it myself.

Rune
--
3D images and anims, include files, tutorials and more:
Rune's World:    http://rsj.mobilixnet.dk (updated June 26)
POV-Ray Users:   http://rsj.mobilixnet.dk/povrayusers/
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> want the color of a material to be, say, rgb 1, but the highlight to be
rgb
> <1,0,0>.

I'll take a crack at this.

texture {
pigment {color rgb 1}
}

texture {
pigment {color rgbt <1, 0, 0, 1>}
finish {phong 1 phong_size 40 metallic}
}

Would be better if phong and specular took a color like every other renderer
out there.

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