I discussed this topic on povray.general already, but I'll discuss it
also here, since I think this is a real bug and not only a "feature".

  When you make a light source 'shadowless', that light source also stops
causing highlights (phong and specular) on objects.
  I don't know if this is intentional or if it's a real bug (can somebody
who knows, eg someone from the povteam reading this, tell me?), but it surely
is a big flaw sometimes.
  I got this problem yesterday. I wanted nice highlights but I didn't want
the shadows. I couldn't. No shadows, no highlights, sorry.
  Making the object shadowless was not an option, since there were other
light sources as well, and those had to cast shadows.

  If this is intentional, then I suggest adding a 'highlightless' keyword
(or whatever) to the light source syntax. This way you could specify if
you want a light source to cause highlights or not.

-- 
main(i){char*_="BdsyFBThhHFBThhHFRz]NFTITQF|DJIFHQhhF";while(i=
*_++)for(;i>1;printf("%s",i-70?i&1?"[]":" ":(i=0,"\n")),i/=2);} /*- Warp. -*/

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On 21 Jan 1999 07:15:51 -0500, Nieminen Mika <war### [at] cctutfi> wrote:

>  I discussed this topic on povray.general already, but I'll discuss it
>also here, since I think this is a real bug and not only a "feature".
>
>  When you make a light source 'shadowless', that light source also stops
>causing highlights (phong and specular) on objects.
>  I don't know if this is intentional or if it's a real bug (can somebody
>who knows, eg someone from the povteam reading this, tell me?), but it surely
>is a big flaw sometimes.
>  I got this problem yesterday. I wanted nice highlights but I didn't want
>the shadows. I couldn't. No shadows, no highlights, sorry.
>  Making the object shadowless was not an option, since there were other
>light sources as well, and those had to cast shadows.
>
>  If this is intentional, then I suggest adding a 'highlightless' keyword
>(or whatever) to the light source syntax. This way you could specify if
>you want a light source to cause highlights or not.

This is built into POV. Shadowless lightsources were introduced with
the purpose to be used as floodlights. At least this is the feeling I
get from the "FLOODLIGHT" light source type I encountered in the
source code. And yes, floodlights or directional lights usually don't
give nice highlights (in real life, I guess that's why they are used)
while providing an overall lightning much better than
ambient_lighting. So the FLOODLIGHT flag skips highlight calculation
at all.
As you suggested, a 'highlighless ' keyword would be useful. Actually,
it is more precise to call the current implementation 'floodlight' and
then have have a 'shadowless'-only keyword, but this would not be
backwards compatible. Or, what is best, have a 'shadowless' and
'highlightless' flag to control both features, made
backwards-comatible by means of the #version directive.

Peter

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