Have you guys seen NVidia's real-time Gas Station demo?  It uses radiosity 
& soft-shadows.  The radiosity must have been done in another renderer and 
applied as texture maps.  The lighting and soft shadows seem to be done in 
real-time.

Is there a way to use Povray to render the required texture maps to use in 
real-time 3D?  I guess it would involve to take each object's side, one at 
a time, render it with an orthogonal camera, scaled to the objects's field 
of view, with the rest of the objects in the scene to "no_image", or 
something like that?

They have a video of the Gas Station demo available:
(you need to put following three lines on one for link)

http://www.nvidia.com/content/5900_videos/index_dl_720.asp?
task=settings&video=http://download.nvidia.com/downloads/5900
_videos/demos/Gas_Station_Demo

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None <Non### [at] onca> wrote:
> Is there a way to use Povray to render the required texture maps to use in 
> real-time 3D?

  The lightmaps used in real-time rendering engines are precalculated
usually with the so-called hemicube algorithm (use google for more info).
The great thing about this algorithm is that it can be used with hardware
(ie. the 3D-card), which accelerates the calculation of the lightmaps
a lot faster.
  Naturally the same job could be done with POV-Ray. The problem would
be that while a 3D-card renders at least a hundred of lightpatches per
second, it would take POV-Ray at least some seconds, if not minutes
(depending on scene complexity) to do one lightpatch.

  Thus, it would be possible, but not very feasible.

  (By the way, with POV-Ray the hemisphere algorithm could be used, which
is the "original" algorithm used by radiosity. The hemicube algorithm is a
variant developed so that 3D-cards could be used for the calculations.
However, the differences are so minimal that there isn't really any
advantage of this fact.)

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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Warp <war### [at] tagpovrayorg> wrote in news:3f356e5a@news.povray.org:

> [...]
>   The lightmaps used in real-time rendering engines are precalculated
> usually with the so-called hemicube algorithm (use google for more
> [...]

Yes, that's exactly what I was wondering, if Povray could be used to pre-
calculate the light-maps and textures for use in real-time 3D.

Thanks very much for the info..., I'll do some reading on that.

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The demos alone that came with my gforce card are amazing to watch.  The
card, unfortunately, only seems to find support in video games.  While we're
on the radiosity topic, I ran across this the other day:

http://bunny.blueskystudios.com/

The good old bunny short film.... one of the few computer animated films to
use radiosity.  I was actual checking out how they did the fur :P

--
Doug Eichenberg
www.getinfo.net/douge
dou### [at] nlsnet

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In article <Xns### [at] 204213191226>, None <Non### [at] onca> 
wrote:

> Yes, that's exactly what I was wondering, if Povray could be used to pre-
> calculate the light-maps and textures for use in real-time 3D.

Technically, it may be possible, but I don't see an easy way to do it, 
or many possible benefits. You could use POV to render the hemicubes, 
which would be really slow. Or you might be able to do some source code 
hacking to output radiosity values in a useable form, but POV radiosity 
makes some simplifications and compromises for speed that are of no help 
for this.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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None wrote:
>Have you guys seen NVidia's real-time Gas Station demo?  It uses radiosity
>& soft-shadows.  The radiosity must have been done in another renderer and
>applied as texture maps.  The lighting and soft shadows seem to be done in
>real-time.
>
>Is there a way to use Povray to render the required texture maps to use in
>real-time 3D?  I guess it would involve to take each object's side, one at
>a time, render it with an orthogonal camera, scaled to the objects's field
>of view, with the rest of the objects in the scene to "no_image", or
>something like that?
>
>They have a video of the Gas Station demo available:
>(you need to put following three lines on one for link)
>
>http://www.nvidia.com/content/5900_videos/index_dl_720.asp?
>task=settings&video=http://download.nvidia.com/downloads/5900
>_videos/demos/Gas_Station_Demo
>

Hi, I'm newbie with pov, but I got involved in the making of a 3D realtime
environment recently, so I think that you need a Baking procedure, I've
seen one in a commercial program that first makes an Atlas map of each
object involved on the baking, then calculates the options that user want
to be baked, such as shadows, radiosity, procedural mapping, etc. So you
get a map that is applied on a second term to the object. The result is
that you get a completely detailed scene and with only ambient lights the
work is done.

Since we are with a free software, I can tell you that Blender can bake and
publish realtime scenes.

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