I got the patterned light sources working, partly working anyway. The 
syntax is:
light_source {POSITION
    pigment {...}
   or
    color ...
    map_type 0
}
Either a plain color or a pigment can be used. The map_type keyword 
controls how the pigment is calculated, 1, 2, and 3 will be spherical 
and cylinderical, where the distance the light has travelled is used for 
the z distance. 0 will be "straight mapping", where the pigment is 
evaluated at each point without any warping or displacement.

I think it will work with photon mapping, I am not sure though. And the 
depth-dependant features don't work yet, so the really interesting 
experiments with photon mapping aren't possible. Also, the pigment is 
not transformed along with the light source. I think it should be, but I 
admit I haven't thought of it much.

I will upload an image to .binaries.images soon.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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What will be the main use of this feature?

  (Btw: My opinion is that povray 3.5 should not be filled with tons of
useless features only because they are "cool"; they only consume space and
make rendering slower (even if not used))

-- 
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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In article <38b91f92@news.povray.org>, Nieminen Juha 
<war### [at] sarakerttunencstutfi> wrote:

>   What will be the main use of this feature?

Probably the thing it will be used for most often is custom spotlights. 
You could control the falloff and the color at each angle precisely. And 
with function patterns, you would have a very versatile way of 
controlling the light source. Then there was the possibility of using it 
as a hologram projector...
The things I find most interesting, like the possibility of using it to 
simulate some of the wave behaviors of light, most likely wouldn't get 
used very much.

>   (Btw: My opinion is that povray 3.5 should not be filled with tons of
> useless features only because they are "cool"; they only consume space and
> make rendering slower (even if not used))

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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Chris Huff wrote:

> The things I find most interesting, like the possibility of using it to
> simulate some of the wave behaviors of light, most likely wouldn't get
> used very much.

Oh really ? That was the first thing I thought of (see my reply to your
thread in .images). If I thought of it I am sure that people interested
in such things will also jump to the same conclusion. I have since thought
of 10 - 1 applications for this feature and I have not concentrated on
it for very long. I see a lot of possibilities for it if it don't break
things in the process.

-- 
Ken Tyler -  1300+ Povray, Graphics, 3D Rendering, and Raytracing Links:
http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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In article <38B### [at] pacbellnet>, lin### [at] povrayorg wrote:

> Oh really ? That was the first thing I thought of (see my reply to your
> thread in .images).

When I said wave behaviors, I meant things like interference patterns. 
While simulating these using ray-tracing would be interesting, I don't 
see why anyone would want to use it in an actual scene.


Another idea: simulating different colors of fluorescent paint on an 
object. Use the light groups: make a white sphere which interacts with a 
patterned light source, and have it be the only thing that light source 
affects. Use another light source at the same position, but unpatterned, 
and set it to affect everything but the sphere. The sphere will be the 
only thing lit up by multi-colored light, which will make it look like 
it is covered with several colors of fluorescent paint.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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Is there some difference between the patterned light source and a regular
light source with a tiny sphere around it with the desired pattern applied?

-- 
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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In article <38b93cb7@news.povray.org>, Nieminen Juha 
<war### [at] sarakerttunencstutfi> wrote:

> Is there some difference between the patterned light source and a 
> regular light source with a tiny sphere around it with the desired 
> pattern applied?

Yes...the patterned light source evaluates a pigment at each point, so 
it depends on position instead of just angle to the light source.(And 
when I get the mappings working, it will also optionally depend on the 
distance the light has travelled.)

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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