A very nice image, I like the lighting and also didn't notice any artifacts
with the radiosity. Is the photograph just mapped onto a plane/box or did
you map it to the inside of a sphere?

My only complaint is I would like to see a higher resolution render ;-)
Especially when you add the furniture etc..

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"Tim Nikias" <JUSTTHELOWERCASE:timISNOTnikias(at)gmx.netWARE> wrote in
message news:43058731@news.povray.org...
> > If you would like a nice leather sofa, feel free to use this one:
> > http://www.onewhiteraven.com/povray_models/pages/image006.php
> > Wings3D model on request if you want to tweak the sagginess of the seats
> or
> > move the cushions.
>
> Thanks for the offer, but I plan on doing all the stuff myself. Just like
I
> script my own particle systems, water simulations and whatnot, I like to
> model my own stuff (especially since I bought Silo, its just so much fun
> :-).
>
> Regards,
> Tim
>

cool, keep us posted on the work.

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> The backdrop was rendered... Nah. It's a photo.

*takes a few breaths and sits back down*

That's a really neat image... I've always wanted to make a CG image that 
looks "sunny". But bathing everything in slightly yellow light just 
makes everything look... slightly yellow. :-S

Oh well...

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> Very nice image. I'm currently trying to model our "house to be
constructed
> in the (hopefully) not so far future". Could you tell me how you did the
> two-pass technique? What material do you use for your glass in the window?

The two-pass technique is also described on my website, here:
http://www.nolights.de/projects/radiosity/radiosity.html

Basically, I render the first pass with high pretrace-settings, a high
error_bound (mostly 0.1) and, of course, save_file. In the second pass, I
use load_file to load the radiosity, set error_bound higher (mostly 0.4 or
0.8) and use pretrace_begin and -end at 1.

Here's the radiosity-block for this scene, quite some high settings used:
  radiosity{
    #if (Save)
      pretrace_start 0.2
      pretrace_end 0.0125
      save_file "windows.rad"
      error_bound 0.1
    #else
      pretrace_start 1
      pretrace_end 1
      load_file "windows.rad"
      error_bound 0.8
    #end
    recursion_limit 2
    minimum_reuse 0.01
    nearest_count 10
    count 900
    brightness 2.0
    always_sample off
  }

As for the window, that's a very plain, transparent pigment with some
reflection:
  pigment{rgbt <1,1,1,1>}
  interior{ior 1.55}
  finish{
    reflection{0,1 fresnel exponent .98}
    diffuse 1
    specular 1 roughness .001
  }

Since I'm using radiosity, I've defaulted "ambient" to 0 (using
#default{finish{ambient 0}}).

Regards,
Tim

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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> A very nice image, I like the lighting and also didn't notice any
artifacts
> with the radiosity. Is the photograph just mapped onto a plane/box or did
> you map it to the inside of a sphere?

It's mapped onto a pair of triangles which are calculated to sit in direct
line of the camera's viewing frustrum, using my Glare-Macros (available on
my website in the Downloads Section). I've simpled used the following setup
to do that:

#declare Camera_Location = <1.32,1.1,-3.8>;
#declare Camera_Look_At = <-1.51,.85,0>;

camera{
  location Camera_Location
  look_at Camera_Look_At
}

#if (!Save)
  #declare Backdrop = texture{pigment{image_map{jpeg "windows_bk4.jpg"}scale
<-1,1,1>}finish{ambient .9 diffuse 0} translate <-.1,.035,0>}
  Glare_PlaceImage(Backdrop,20)
#end

The #if is to check if I'm doing the 1st Pass (collecting  samples) or the
2nd, to avoid placing samples onto the image or having the image itself
influence the calculations.

> My only complaint is I would like to see a higher resolution render ;-)
> Especially when you add the furniture etc..

Sure thing, once this is done and rendered at an appropriate resolution, it
should be available for download on my website, but I'll post on the
development as well.

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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> This is a really good example how smooth and appealing lighting in such
> a scene can be done in POV-Ray with quite reasonable render times (care
> to mention?)

I've written a post in reply to my image which covers the radiosity-settings
and the rendering times for the two passes. Since so many asked, I only went
through the hassle of answering once. :-)

> And i think the lighting - despite not being highly accurate - is better
> than in a lot of images of similar scenes done with commercial renderers.

High praise (though most of it goes to POV-Ray, but I had a little influence
in it. :-) Thank you very much!

But I agree totally, there are quite a few commercial renderers which I find
truly lacking, though one could argue that if an experienced User would sit
at it, he/she would get good results too. It's not like this is the first
time I've played with radiosity. :-)

Regards,
Tim

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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> Very nice image!

Thank you!

> I'm wondering what was the rendering time and what radiosity settings have
> you used? The radiosity looks very well. My attempts were never so good,
> though they've taken many hours to render.

I've written a reply to my original post, so that I wouldn't have to post
the same answer in concern of radiosity-settings to every one. I'm a bit
lazy, I admit it. :-)

Regards,
Tim

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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First off, thanks to all for the praise, it's nice to get some good feedback
and feel proud to have accomplished something that's worth noting. :-)

As several have voiced questions concerning the rendering-times and the
radiosity-settings, here's the radiosity-block from the global_settings:

  radiosity{
    #if (Save)
      pretrace_start 0.2
      pretrace_end 0.0125
      save_file "windows.rad"
      error_bound 0.1
    #else
      pretrace_start 1
      pretrace_end 1
      load_file "windows.rad"
      error_bound 0.8
    #end
    recursion_limit 2
    minimum_reuse 0.01
    nearest_count 10
    count 900
    brightness 2.0
    always_sample off
  }

I simply #declare Save in the beginning to decide if I'm doing the 1st Pass
(collecting lots of samples and save it) or the 2nd Pass
(combining/averaging several samples by using a higher error_bound).

My PC is a 2.4Ghz Athlon XP running on Win2000 with 768MB DDR-RAM.

The 1st Pass took 13 minutes, but the pretracing went real fast and the
final render took quite long. No glass, backdrops or complex textures used
in that pass, but I kept the floor and the metal parts on the windows
slightly reflective.

The 2nd Pass rendering, with Anti-Aliasing at 800x600 with +am2 +a0.2 +r2
took 15 minutes.

Note that I've described this technique on my website as well, and the
origins of the two-pass render are in these same newsgroups, developed by
various Povers quite some time ago, so I don't claim full responsibility for
the good outcome. :-)

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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> That's a really neat image...

Thanks!

> I've always wanted to make a CG image that
> looks "sunny". But bathing everything in slightly yellow light just
> makes everything look... slightly yellow. :-S

Well, I guess usually, sunlight is more white than yellow, and only tends to
get orange/reddish at early or late times. So maybe you just picked the
wrong color? Ambient colors also play a major role. There's no shame in
looking at photographs and using the RGB-Values from there... :-)

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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I have to take my comment about the artifact above the left window back.
Just noticed today that I actually accidently had the window pass on through
the ceiling, so the "artifact" was in fact a proper reflection. Thus, the
radiosity doesn't have to be tweaked to get even better results, as you will
see when I post updates.

Regards,
Tim

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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