TonyB <ben### [at] panamaphoenixnet> wrote:
: There can be a max of 30 user defined Light groups

  Why?

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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On 16 Nov 1999 07:27:57 -0500, Nieminen Juha wrote:
>TonyB <ben### [at] panamaphoenixnet> wrote:
>: There can be a max of 30 user defined Light groups
>
>  Why?

Because MCB used a 32-bit integer to store which light groups are 
in effect for a given object or light source.  It's a design decision,
basically.

-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html

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On Tue, 16 Nov 1999 01:07:04 -0500, "Mark Wagner"
<mar### [at] gtenet> wrote:

>On a similar subject, I think the 'no_shadow' keyword should be removed, and
>the keyword 'shadowless' should work in place of it.  As is, there are two
>keywords that are doing essentially the same thing, and it is difficult to
>remember which one is for objects, and which one is for lights.
>
>Mark

Not quite. Shadowless in a light source turns off not only shadow ray
calculations for this particular light but also any specular
highlighting. It was initially intended for use as a fill light, and
there are references in the source code inticating this.


Peter Popov
ICQ: 15002700

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Nieminen Juha wrote:
> Charles <cfu### [at] enternet> wrote:
> : I would
> : also add, though, that I never understood why the default was to
> : NOT accept media unless a keyword was added.
> 
>   Usually fog doesn't go inside objects. That's why.

Ahhhh, yes. Fog. In six years, I've only had two uses for it, and
neither involved transparent objects, so the first time the hollow
keyword became an issue for me was when halo hit the scene. I had
forgotten (or never read) any previous applications of the word.

>   There might be situations where you want media inside an object but not
> fog (or other medias). Perhaps there should be more keywords to specify
> these kind of things, as someone already suggested.

Yes, that's  true. For flexibility's sake, you probably shouldn't
have fog and media accepted or forbidden with the same keyword. 

Technically for maximum flexibility, it wouldn't hurt if objects 
could accept or forbid any number of named media in whatever 
combinations the artist sees fit, although I don't know how much more
complexity that might add to the code internally, so I'm not sure
whether people would consider it worth the trouble. 

It might, at the least, involve adding some kind of "name" keyword 
inside media that would enable them to become recognizable to the 
renderer as distinct independent named entities. Then you could
add lines to your object such as...

forbid FireMedia //forbid the specific named entity "FireMedia"
//or...
forbid fog //forbid fog within the object boundary

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Ron Parker wrote in message ...
>On 16 Nov 1999 07:27:57 -0500, Nieminen Juha wrote:
>>TonyB <ben### [at] panamaphoenixnet> wrote:
>>: There can be a max of 30 user defined Light groups
>>
>>  Why?
>
>Because MCB used a 32-bit integer to store which light groups are
>in effect for a given object or light source.  It's a design decision,
>basically.


Just today I finished debugging a modification to the Superpatch which
removes the limits on the number of light groups and the number of entries
in a pure spline.  I can send you the modifications tomorrow if you want me
to.

Mark

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Peter Popov wrote in message <0dMxOC8Ugw8=f17WiV4EWjVSy1kk@4ax.com>...
>On Tue, 16 Nov 1999 01:07:04 -0500, "Mark Wagner"
><mar### [at] gtenet> wrote:
>
>>On a similar subject, I think the 'no_shadow' keyword should be removed,
and
>>the keyword 'shadowless' should work in place of it.  As is, there are two
>>keywords that are doing essentially the same thing, and it is difficult to
>>remember which one is for objects, and which one is for lights.
>>
>>Mark
>
>Not quite. Shadowless in a light source turns off not only shadow ray
>calculations for this particular light but also any specular
>highlighting. It was initially intended for use as a fill light, and
>there are references in the source code inticating this.


True, but you will never need to use both the 'shadowless' keyword and the
'no_shadow' keyword on the same object, so there is no need for two keywords
for the general effect of eliminating shadows.

Mark

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Nieminen Juha wrote in message <3831214f@news.povray.org>...
>  Or perhaps there should be more keywords to control how shadows are
>calculated for an object:
>
>  self_shadow [on|off]  // specifies whether it should cast shadows on
itself
>                        // or not (ie. if off, it will be shadowless for
>                        // itself but not for other objects)
You can get this effect with either finish{ambient 1 diffuse 0} or in UVPov
specifying 'double_illuminate', depending on the specific effect you want.


Mark

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On Wed, 17 Nov 1999 01:01:37 -0500, "Mark Wagner"
<mar### [at] gtenet> wrote:

>>Not quite. Shadowless in a light source turns off not only shadow ray
>>calculations for this particular light but also any specular
>>highlighting. It was initially intended for use as a fill light, and
>>there are references in the source code inticating this.
>
>
>True, but you will never need to use both the 'shadowless' keyword and the
>'no_shadow' keyword on the same object, so there is no need for two keywords
>for the general effect of eliminating shadows.
>
>Mark

The best solution would be to have keywords controlling highlights and
shadows on a per-object and per-light basis. I don't know, does the
light groups patch offer control over highlighting?


Peter Popov
ICQ: 15002700

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Mark Wagner <mar### [at] gtenet> wrote:
: You can get this effect with either finish{ambient 1 diffuse 0}

  No, that will not achieve that effect. That would mean that the object
is not shaded. That's not the same as not casting shadows on itself.
  A sphere can't cast shadows on itself but a torus can (due to their
form).

: or in UVPov
: specifying 'double_illuminate', depending on the specific effect you want.

  I think that double_illuminate will not eliminate any shadow calculations.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Peter Popov <pet### [at] usanet> wrote:
: Not quite. Shadowless in a light source turns off not only shadow ray
: calculations for this particular light but also any specular
: highlighting.

  In my opinion this should be changed. I have had scenes where I really
wanted the highlights but not the shadows (for one light source; for the
other light sources I wanted both).

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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