In article <3ea03fdb@news.povray.org> , Andreas Kreisig <and### [at] gmxde> 
wrote:

> BTW: to work
> with primitives (CSG) is somewhat outdated.

No, here you are wrong.  It simply happens that CSG is harder to do if you
don't use plain ray-tracing.  And the default renderers shipped with any
commercial package today do not use plain ray-tracing, but various hybrid
scanline/ray-tracing methods.  And those methods cannot easily do CSG, but
they need to precompute what they call CSG in the modeler interfaces...

    Thorsten

____________________________________________________
Thorsten Froehlich
e-mail: mac### [at] povrayorg

I am a member of the POV-Ray Team.
Visit POV-Ray on the web: http://mac.povray.org

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On Fri, 18 Apr 2003 20:17:55 +0200, Andreas Kreisig <and### [at] gmxde> wrote:
> > http://news.povray.org/povray.binaries.images/19709/127888/MyCar.jpg
> > http://news.povray.org/povray.binaries.images/30145/214068/recar3dc5.jpg
> > http://news.povray.org/povray.binaries.images/22626/156738/susp.jpg
> > http://news.povray.org/povray.binaries.images/30945/220060/FORDTRCK.jpg
> > http://news.povray.org/povray.binaries.images/31112/221106/WALL.jpg
>
> That's exactly what I mean: this images shows something like a car, but no 
> really car.

Is that becouse they have no name ?

> When I write cars I mean something like this:
>
> http://www.kk.iij4u.or.jp/~knight/images/gallery_image/enzo_re.jpg
> http://www.ays-arts.de/gallery/lw7/mz6-01.jpg
> http://www.simonreeves.co.uk/3d/rs6/rs6front.jpg

You mean level of details ? Background ? Making exactly along sheet of plans ?
In what way those cars are better then those from my links ? And why Nekar has
won with his model?

> > You have to understand that everything what modeller do is just some
> > interactive action to get input for algorithm performed over primitive
> > objects and textures to make some complexity which looks soft, organic
> > etc.
>
> The difference is that a modeller like Maya or XSI don't need algorithms to 
> work with primitives.

They usually need triangles. Triangle is one of primitives, isn't it?

> They just store the x|y|z coordinates. BTW: to work 
> with primitives (CSG) is somewhat outdated. Nowadays most artists use 
> boxmodelling, splinecages or something similar.

And some use POV. Please do not compare images from povray.binaries.images with
works of artists working with other packages. Please compare POV artists with
artists in other packages. Please compare scientist working with POV and
scientist working with other packages.

> Impossible or very hard to 
> do with POV-Rays SDL. To get smoothed results you have to use NURBS, 
> subdivision surfaces, Hypernurbs, weighted vertices or whatever. All this 
> needs a modeller when you want to get good results because you need the 
> optical feedback.

Yes and no. Nobody is saying POV is for every work.

> > And as such this action can be recreated in scripting language with
> > necessary programing capabilities and set of 3D functions to create
> > primitives. The difference is that in modeller everything is 'on-screen'
> > in windows while in SDL everything is 'in-manual' and 'in-brain' ;-)
>
> True but misleading. When I make something more complex in Wings3D (a great 
> tool!!) then I have to tweak and fine tune a lot. When you use an algorithm 
> based language you don't have enough controll to move one vertex by one. 

Yes. Because you develope algorithm to work the way you want. If algorithm is
good you do not need to move one vertex. If algorithm is not best you can
"postprocess" otput outputing data and introducing some noise with just one
loop. And I do not say POV is better than modelers here. Some users work one
way. Some users work another way. Some minds are oriented on view and some are
oriented on concept, coordinates, paths and properities expressed with values.
For some pixel resolution is the truth. For some it is floating point accuracy.

> And you don't want to tell me that you make an object by using a hand coded 
> mesh2?

That's because you seem think trangle-oriented modelling is the only way.
CSG is another:
http://news.povray.org/search/advanced/?s=Rasmussen&g=povray.binaries.images&a=1
Isosurface is another:
http://news.povray.org/povray.binaries.images/13780/
http://news.povray.org/povray.binaries.images/13083/
Blob is another. Media is another.

> This is not realistic of course but try something like this with SDL. I 
> needed 5 hours to build it in Wings - it was just a test to figure out how 
> Wings works.

Great! You made head in one tool. Now you can use another tool to make another
element of scene. In other words. You have head. Put a tree in perspective. Nice
unique tree. With enough resolution for high quality image (8000x6000). With
great SDL macros written by somebody it takes seconds. And you can modify it to
go outside of some area (head?). Can you be faster with modeller ?

> Hey, I don't want to start a flame war here. POV-Ray is a great tool but the 
> SDL is limited by its concept not by the user. At least under practical 
> circumstances.

No. Under lazyness and unpatience of user ;-)

ABX

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On Fri, 18 Apr 2003 20:17:55 +0200, Andreas Kreisig <and### [at] gmxde> wrote:
> Nowadays most artists

BTW: How nowadays artists solve distributed workgroup cooperation?

ABX

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ingo wrote:
> How many hours did it take DAZ to create Vicky? Does she look realistic?

Vicky was not built by hand.  Vicky was made using a 3d-scanner.
Hideously expensive to own, not exactly cheap to rent use of one
either, but that's how they build human meshes that look realistic.

-- 
Tim Cook
http://home.bellsouth.net/p/PWP-empyrean

-----BEGIN GEEK CODE BLOCK-----
Version: 3.12
GFA dpu- s: a?-- C++(++++) U P? L E--- W++(+++)>$
N++ o? K- w(+) O? M-(--) V? PS+(+++) PE(--) Y(--)
PGP-(--) t* 5++>+++++ X+ R* tv+ b++(+++) DI
D++(---) G(++) e*>++ h+ !r--- !y--
------END GEEK CODE BLOCK------

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Andreas Kreisig wrote:
> 
> [...]
> 
> The difference is that a modeller like Maya or XSI don't need algorithms to
> work with primitives. They just store the x|y|z coordinates. BTW: to work
> with primitives (CSG) is somewhat outdated. Nowadays most artists use
> boxmodelling, splinecages or something similar. 

Hah!

Don't believe all the stuff the marketing guys from the CG industry are
trying to tell you.  They are trying to sell their software and if it
can't handle anything but triangles because it works with scanline
rendering techniques triangles are of course presented as the only way to
represent geometries efficiently.  Apart from that you will have a hard
time creating a nice tree or anything similarly detailed by hand.  It's
just the contrary of being outdated - with increasing computation power
algorithmically generated geometry will become more and more important
because the time necessary to model complex things by hand will no more be
affordable.

As an example - you will hardly find a detailed tree or terrain model that
is created manually.  On the other hand both can be created with POV-SDL
very efficiently.

Christoph

-- 
POV-Ray tutorials, include files, Sim-POV,
HCR-Edit and more: http://www.tu-bs.de/~y0013390/
Last updated 28 Feb. 2003 _____./\/^>_*_<^\/\.______

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Yes, SDL is limited as there are many things (mostly women and cars) 
which are really difficult to describe in it and you cant get imidiate 
visual feedback but modelers are as limited as there are also many 
things (the grass and the trees) which are best described algorithmically.

I think the best you can do is to combine the two approaches, you 
wouldn't want to model a forest but deciding what it will look like by 
painting some maps to controll some paramenters adding some noise and 
then have a cool forest which although its random is inside the 
parameters you wanted it to be is really powerfull.

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Thorsten Froehlich wrote:
> In article <3ea03fdb@news.povray.org> , Andreas Kreisig <and### [at] gmxde> 
> wrote:
> 
> 
>>BTW: to work
>>with primitives (CSG) is somewhat outdated.
> 
> 
> No, here you are wrong.  It simply happens that CSG is harder to do if you
> don't use plain ray-tracing.  

I think even if people used plain raytracing, they wouldn't use CSG as 
their primary modelling method.

>And the default renderers shipped with any
> commercial package today do not use plain ray-tracing, but various hybrid
> scanline/ray-tracing methods.  

Are you sure? Cinema4d seems to do raytracing and when I last saw it you 
could do "zu Grundobjekt konvertieren" when you were doing CSG with 
primitives.

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in news:3ea05673@news.povray.org Timothy R. Cook wrote:

>> How many hours did it take DAZ to create Vicky? Does she look
>> realistic? 
> 
> Vicky was not built by hand.

I knew that ;)


Ingo

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in news:3EA06029.C923BFC9@gmx.de Christoph Hormann wrote:

> with increasing computation power
> algorithmically generated geometry will become more and more
> important because the time necessary to model complex things by hand
> will no more be affordable.
> 

And in the future POV-Ray will have a groundbreaking DNA{} object. You 
yust add the right DNA-sequence to it and the model will be build.

Ingo

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In article <3ea07c18$1@news.povray.org> , Simon Adameit 
<sim### [at] gaussschule-bsde>  wrote:

> Are you sure? Cinema4d seems to do raytracing

Yes, it is the closest you can get to plain ray-tracing.  Still, it is
hybrid method as it relies at least on various light and reflection tricks;
at least that is what the images suggest when looking closely at light,
shadow and reflection compared to knwon ray-traced images.  I actually
downloaded to manual (the whole 42 MB), but it does not say anything about
technical issues at all :-(

> and when I last saw it you
> could do "zu Grundobjekt konvertieren" when you were doing CSG with
> primitives.

That sure sounds like it could have something to do with primitives, but it
is very hard to tell without actually seeing their code...

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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