I'm happy to hear that Christopher,
what I will do is preparing a package for you with comparsion shots and some
time frames, the technology itself is not quicker than gi solutions but the
results look definetly different. due to the fact that the files I have to
sent will be a bit bigger than usual could you contact me under
Tob### [at] gmxde?

Best regards,

Thorsten

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McHannemann schrieb:

> I'm happy to hear that Christopher,
> what I will do is preparing a package for you with comparsion shots and some
> time frames, the technology itself is not quicker than gi solutions but the
> results look definetly different. due to the fact that the files I have to
> sent will be a bit bigger than usual could you contact me under
> Tob### [at] gmxde?

If you have some useful comparisons you should make them available to 
everyone.  It is unsure if i have the time to work on this at all so it 
would not be a good idea to send them privately to me.  In most cases 
size restrictions on this server should be sufficiently broad to post 
example images (in p.b.i of course).

-- Christoph

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Ben Chambers <ben### [at] pacificwebguycom> wrote:
> Actually, this brings up one point I've run into in the past: since 
> POV-Ray computes radiosity samples by tracing rays from the camera, and 
> then lighting them, I've run into some issues in scenes lit entirely by 
> radiosity that don't light up the way they should (for instance, if a 
> large object with high ambience is partially (or entirely) out of view).

  Perhaps your settings were just too low?

  Care to give a small example scene?

-- 
                                                          - Warp

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Warp wrote:
>   Perhaps your settings were just too low?
> 
>   Care to give a small example scene?
> 

I don't have any lying around, though it would be trivial to construct 
an artificial scene showing this.

However, no matter how high your settings are, an ambient object which 
is completely off screen will never light the scene, no matter its size 
or brightness.

...Chambers

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45c96904$1@news.povray.org...
> However, no matter how high your settings are, an ambient object which is 
> completely off screen will never light the scene, no matter its size or 
> brightness.

Hmm, this always worked OK for me. Are you sure that in your examples the 
ambient object wasn't blocked by something else?

global_settings {radiosity {count 1600 error_bound 1}}
camera {right x*1.33 location y look_at y+z}
sphere{0,0.5 translate <-2,2.5,-1> texture{pigment{rgb x} finish{ambient 
100}}}
sphere{0,0.5 translate <0,2.5,-1> texture{pigment{rgb y} finish{ambient 
100}}}
sphere{0,0.5 translate <2,2.5,-1> texture{pigment{rgb z} finish{ambient 
100}}}
box{<-3,0,-2>,<3,3,6> texture{pigment{rgb 1}finish{ambient 0}}}

G.

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45c82c5a$1@news.povray.org...

> great.  But you should take care this is a valid comparison (i.e. no mesh 
> only scene compared to a complex CSG in POV-Ray) and giving render times 
> is essential of course.  Gilles made such a comparison for C4D some time 
> ago (the result was that the techniques seem very similar in results 
> although there are also differences).

This was in 2003 with C4D's "advanced render", and indeed the techniques 
seemed very similar to POV-Ray's own. However, I recently tested the same 
scene with finalRender and its Advanced Quasi Montecarlo engine and the gain 
in speed and quality is really amazing (artifact-free render of the scene in 
10-20% of the original render time). I don't know whether these latest GI 
(proprietary) techniques would work for scenes not based on meshes, but they 
are quite impressive. finalRender can end up crawling like any other 
renderer, but one can throw a lot of things at it before it does.

G.

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Ben Chambers <ben### [at] pacificwebguycom> wrote:
> However, no matter how high your settings are, an ambient object which
> is completely off screen will never light the scene, no matter its size
> or brightness.

I too have lit several scenes using only radiosity, with a large white
sphere behind the camera acting as a light source (this was using MegaPOV,
although I'm unaware of any differences in this regard). My count was
between 800-1200, so perhaps your settings were indeed too low as Warp
suggested.

Bill

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Ben Chambers <ben### [at] pacificwebguycom> wrote:
> However, no matter how high your settings are, an ambient object which 
> is completely off screen will never light the scene, no matter its size 
> or brightness.

  Care to explain why? I can't think of any reason why being on-screen
would have anything at all to do with that. Radiosity samples don't care
where the camera is looking at. It shoots rays to all directions.

-- 
                                                          - Warp

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Gilles Tran schrieb:
> 
> This was in 2003 with C4D's "advanced render", and indeed the techniques 
> seemed very similar to POV-Ray's own. However, I recently tested the same 
> scene with finalRender and its Advanced Quasi Montecarlo engine and the gain 
> in speed and quality is really amazing (artifact-free render of the scene in 
> 10-20% of the original render time). I don't know whether these latest GI 
> (proprietary) techniques would work for scenes not based on meshes, but they 
> are quite impressive. finalRender can end up crawling like any other 
> renderer, but one can throw a lot of things at it before it does.

It would be great to see some results.  Testing with a single relatively 
simple sample scene is of course not really representative but still it 
would be very interesting.  Note there can of course be a difference 
between good-looking and accurate results.

-- Christoph

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Warp wrote:
> Ben Chambers <ben### [at] pacificwebguycom> wrote:
>> However, no matter how high your settings are, an ambient object which 
>> is completely off screen will never light the scene, no matter its size 
>> or brightness.
> 
>   Care to explain why? I can't think of any reason why being on-screen
> would have anything at all to do with that. Radiosity samples don't care
> where the camera is looking at. It shoots rays to all directions.
> 

It appears I've been proven wrong once again, and here's where I got 
confused.

I was under the impression that the Radiosity pretrace only created 
samples from objects that were on-screen.  Since ideally the pretrace 
will create all necessary samples and further sampling would be 
unnecessary, this would result in only having samples for onscreen objects.

Second, I never thought to bump up the count setting to 1600, as Gilles 
suggested.  I always assumed that 100-150 was enough, as further detail 
isn't noticable in many scenes.

Some quick tests I just did show that simply going with much higher 
settings than I had (in fact, before I would have called them insane :) 
) was sufficient.

I stand corrected ;)

...Chambers

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