I was looking at the source for the scene file "Brilliant" and noticed
that the artist used vectors for describing the reflection values of each
facet. This possibility had totaly excaped me until now. What benefit
if any is gained by doing so ?

An example: finish { reflection <0.5,0.75,0.5> }

--
Ken Tyler

tyl### [at] pacbellnet

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i think it defines how each colour will be reflected...

//Spider

Ken wrote:
> 
> I was looking at the source for the scene file "Brilliant" and noticed
> that the artist used vectors for describing the reflection values of each
> facet. This possibility had totaly excaped me until now. What benefit
> if any is gained by doing so ?
> 
> An example: finish { reflection <0.5,0.75,0.5> }
> 
> --
> Ken Tyler
> 
> tyl### [at] pacbellnet

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Ken wrote:
> 
> I was looking at the source for the scene file "Brilliant" and noticed
> that the artist used vectors for describing the reflection values of each
> facet. This possibility had totaly excaped me until now. What benefit
> if any is gained by doing so ?
> 
> An example: finish { reflection <0.5,0.75,0.5> }

It modifies the color of the reflected light.  You could, for instance,
have a silver mirror (neutral tones in the pigment) that reflected a blue
image of the things in view.

Regards,
John

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Thanks John, Spider.

--
Ken Tyler

tyl### [at] pacbellnet

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Ken wrote:
> 
> I was looking at the source for the scene file "Brilliant" and noticed
> that the artist used vectors for describing the reflection values of each
> facet. This possibility had totaly excaped me until now. What benefit
> if any is gained by doing so ?
> 
> An example: finish { reflection <0.5,0.75,0.5> }
> 
> --
> Ken Tyler
> 
> tyl### [at] pacbellnet

I have used that feature. The vector is a colorvector :) rgb that is.

cu
Bjarne Nygaard

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Surprised that you, Ken, of all people had failed to notice the
vectorable reflection before now. Though I must admit I did not, and
presume, do not (which comes in handy) know all there is to know.
Cross-threading a bit here, but, I tried to do a mixture of spectral
dispersion and reflection color shifting together to no avail.
Seems that the reflection simply refuses to be averaged as refraction
does. Been puzzled ever since. As others may already know, normals have
a difficult time being layered or averaged too (or so I think) so it
follows that there are probably many such impossible(?) characteristics,
along with a few good pluses which balances things out thank goodness.


Ken wrote:
> 
> I was looking at the source for the scene file "Brilliant" and noticed
> that the artist used vectors for describing the reflection values of each
> facet. This possibility had totaly excaped me until now. What benefit
> if any is gained by doing so ?
> 
> An example: finish { reflection <0.5,0.75,0.5> }
> 
> --
> Ken Tyler
> 
> tyl### [at] pacbellnet

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/POVring.htm
=Bob

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Bob Hughes wrote:

> Surprised that you, Ken, of all people had failed to notice the
> vectorable reflection before now.--

It just goes to show that even for someone who is well versed with
the program there are still things to learn. There are so many variables
in this program I doubt that I will ever learn them all. Can you without
looking right now type every possible pigment pattern type ? I did it
once to test myself about three months ago. I missed only two. One
of which I didn't know exsisted (new for 3.1).

Did you know you can use a negative number for a cone diameter and
end up with two cones kissing at their points ? Try this on for size:
cone{x*-1,1,x*1,-1 pigment{rgb 1}}

Who would ever think of using negative values like this especialy since
it's not documented anywhere ? I found out by way of typo. Wanna
see weird ? Try negative values with superellipsoids.
There are some other unique things you can do that are not documented
because the program has so much flexibility that I imagine even the
programmers don't know all that it can do.

I'm not to blame for not knowing because I'm only human and not some
perfect machine. I know little about media and next to nothing about using
blobs. Who cares ? Theres plenty of other features to keep me busy for
years. Implementing and using nested and recursive while loops will keep
me busy for most of 1999 and then it's time to master macros

Ken Tyler

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Ken wrote:
> 
> Bob Hughes wrote:
> 
> > Surprised that you, Ken, of all people had failed to notice the
> > vectorable reflection before now.--
> 
> It just goes to show that even for someone who is well versed with
> the program there are still things to learn. There are so many variables
> in this program I doubt that I will ever learn them all. Can you without
> looking right now type every possible pigment pattern type ? I did it
> once to test myself about three months ago. I missed only two. One
> of which I didn't know exsisted (new for 3.1).
Oopa... Skilled as imagined.

> 
> Did you know you can use a negative number for a cone diameter and
> end up with two cones kissing at their points ? Try this on for size:
> cone{x*-1,1,x*1,-1 pigment{rgb 1}}
Kewl... 

> 
> Who would ever think of using negative values like this especialy since
> it's not documented anywhere ? I found out by way of typo. Wanna
> see weird ? Try negative values with superellipsoids.
> There are some other unique things you can do that are not documented
> because the program has so much flexibility that I imagine even the
> programmers don't know all that it can do.
Porbably not, but then, programmers in general aren't noteworthy for their great
patience
in documentation.... (I know, I'm one of them.)

> 
> I'm not to blame for not knowing because I'm only human and not some
> perfect machine. I know little about media and next to nothing about using
> blobs. Who cares ? Theres plenty of other features to keep me busy for
> years. Implementing and using nested and recursive while loops will keep
> me busy for most of 1999 and then it's time to master macros
We don't blame you... I wonder what would happen the day I stopped learning and
testing in
pov.... Hmm. I maybe will get a scene finished... Yeah, that's it.


//Spider

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Actually, at least up to now there as little point in using rgb values in
reflection. The following would give exactly the same results:

pigment {rgb 1} finish {reflection <1,0,0>}
pigment {rgb <1,0,0>} finish {reflection 1}

i.e. you can do the same thing with pigments.
Now with the variable reflection patch, I'm not so sure... Must try it out.

Margus

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Margus Ramst wrote:
> 
> Actually, at least up to now there as little point in using rgb values in
> reflection. The following would give exactly the same results:
> 
> pigment {rgb 1} finish {reflection <1,0,0>}
> pigment {rgb <1,0,0>} finish {reflection 1}
> 
> i.e. you can do the same thing with pigments.
> Now with the variable reflection patch, I'm not so sure... Must try it out.
> 
> Margus

Not true, in the first instance the object has a red pigment and in the
second, white.

Try the following

plane{	-z,0
  pigment{White}
  finish{ reflection Red } }
sphere{
  <3,0,-3>,1
  pigment{Blue+Green} }

White plane, no reflection of the sphere because the plane reflects none
of the primaries in the sphere's pigment.

Cheers, PoD.

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