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From: Jim Charter
Subject: Mesh etc.
Date: 4 Mar 2004 15:53:55
Message: <40479763@news.povray.org>
POV-Ray has a long and distinguished history supporting hand-coded csg 
modelling and procedural textures.  Seemingly, as a way to extend POV's 
capabilities and include the import of mesh models from the web, 
sopisticated mesh2 support was added to POV.  With the recent boom in 
the availability of mesh (polygonal) modellers in the 
freeware/shareware/hobbiest space, more and more POVers seem to be 
embracing mesh modelling as an creative tool.

What are peoples' thoughts on this.  Who are beginning to experiment 
with mesh tools and what tools are you using?  How do you see them 
fitting in with your style and expressive intentions?

Further, commercial software producers seem to understand the role of 
the amateur market in creating a workerpool with software skills.  So 
marketshare there can influence marketshare in the commercial venue. 
This has lead to highend vendors making training versions of these 
powerful products available to the hobbiest community.  What role does 
this leave for POV?


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From: Warp
Subject: Re: Mesh etc.
Date: 5 Mar 2004 07:55:43
Message: <404878cf@news.povray.org>
Jim Charter <jrc### [at] msncom> wrote:
> Seemingly, as a way to extend POV's 
> capabilities and include the import of mesh models from the web, 
> sopisticated mesh2 support was added to POV.

  Actually no.

  mesh2 is not a new primitive type added to POV-Ray 3.5. It's just an
alternative syntax for an already-existing primitive, the mesh (which
was added to POV-Ray 3.1 to effectively replace unions of triangles,
which consumed more memory).

  mesh2 was not added for enhanced support with third-party programs
(because you could already do the same things with a mesh, which most
third-party programs supporting POV-Ray did), but to make the pov files
containing meshes smaller (and probably a bit faster to parse). mesh2 does
not add anything new renderwise which mesh would not support, only
syntaxwise.
  So the main advantage of mesh2 over mesh is smaller file size.

-- 
#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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From: Gilles Tran
Subject: Re: Mesh etc.
Date: 5 Mar 2004 09:45:11
Message: <40489277@news.povray.org>

news:404878cf@news.povray.org...

>   Actually no.

Actually yes ;-)
You forgot uv-mapping which offers uv-mapping on meshes for the masses, and
it certainly made a big difference. I'm aware that uv-mapping is somehow
feasible with a union of triangles (by giving a texture to every vertex),
but it's not exactly a practical method. uv-mapping is one feature that
helped to build a bridge between POV-Ray and commercial applications. We can
now model and texture objects in any modeller and render them in POV-Ray.

Also, I wouldn't play down the smaller size advantage. The mesh2 format
gives mesh sizes which are roughly half of what they are with the old mesh
format. They are created much faster, parse much faster and can be loaded
much faster in an editor if necessary. As a long-time mesh user, this had a
major influence on the way I would use meshes, as it cut down drastically
the time needed to manage them. So, from a user's standpoint, mesh2 is
certainly a new feature, since it allows things that were difficult or
impossible to do without it.

G.


**********************
http://www.oyonale.com
**********************
- Graphic experiments
- POV-Ray and Poser computer images
- Posters


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From: ingo
Subject: Re: Mesh etc.
Date: 5 Mar 2004 11:03:02
Message: <Xns94A3AD724237Aseed7@news.povray.org>
in news:40479763@news.povray.org Jim Charter wrote:

> [...] and what tools are you using?

For me an interseting thing with mesh2 is that it is easier to create 
complex mesh' by using macros within POV-Ray SDL.

Ingo


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From: Gilles Tran
Subject: Re: Mesh etc.
Date: 5 Mar 2004 19:20:31
Message: <4049194f$1@news.povray.org>

news:40479763@news.povray.org...
> What are peoples' thoughts on this.  Who are beginning to experiment
> with mesh tools and what tools are you using?  How do you see them
> fitting in with your style and expressive intentions?

For some time now, most of my images have been basically mesh-based. It
seems to have been a natural evolution.

Until recently, primitive-based modelling had a real superiority over mesh
modelling. For the average POVer with a regular desktop machine, meshes were
just too heavy to handle: a character, tree or car model must be 20-40 Mb
(in mesh2, twice that number in 3.1 mesh) to look good enough at screen
resolution. Smaller meshes, while easier to handle, tend to look ugly due to
the lower poly number.  By comparison, a primitive-based object required
little parsing time and scales up very gracefully (it's always smooth).
Thanks to POV-Ray's amazing number of complex primitives and to its SDL, it
has been possible to create extremely complex images out of primitives.

But now, the current machines have enough RAM to digest gigantic meshes
without complaining so that primitives have become much less competitive.
This is why, for instance, my Maketree objects are no longer interesting,
since we have POV-Tree, which exports in mesh (with a better algorithm) and
allows the creation of entire forests thanks to mesh instanciation.

In some way, the limitations of primitives were like the proverbial elephant
in the middle of the room... There were objects that were impossible or at
least very difficult to represent, so we didn't talk about them :) This
concerns characters, of course, but in fact most objects in the real world
are hard to do right with primitives (or bezier patches) if only because
they have those little rounded edges...
For me, Poser (in 1996) and uv-mapping (in 1999) really opened the door to
mesh use in POV-Ray but it's only recently that I made the jump and started
modelling stuff myself, first in Rhino, then in Wings and now in Cinema4D
(Blender I learned for a week but didn't like enough to continue with it).

The big remaining issue for hobbyists, however, is uv-mapping. AFAIK there
is no free uv-mapping tool allowing real-time 3D painting and some
automatisation for vertex unwrapping (such as the expensive Bodypaint).
Until we have such a tool, mapping will remain a limitation for mesh users.

> Further, commercial software producers seem to understand the role of
> the amateur market in creating a workerpool with software skills.  So
> marketshare there can influence marketshare in the commercial venue.
> This has lead to highend vendors making training versions of these
> powerful products available to the hobbiest community.  What role does
> this leave for POV?

In fact, I'm rather under the impression that commercial software vendors
tend to shun the amateur market, simply because the money is in professional
production, no with the penniless hobbyists. Poser, for instance, is now
sold by the makers of Shade, a Japanese professional 3D software. Xfrog is
no longer a stand-alone product (though the 3.5 version is still available)
but a plug-in for C4D. Accordingly, while POV-Ray images find their way in
magazines and books, articles about POV-Ray are not exactly in high demand.
True, the highend vendors make training versions available, but it's more an
attempt to lure future paying professional users (these versions are
crippled or unusable for final professional work) than to woo hobbyists,
most of whom won't be able to fork over 2000-7000$ for the full version +
the 1000$ plug-ins.  POV-Ray seems relatively safe from this sort of
competition.

G.


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From: gonzo
Subject: Re: Mesh etc.
Date: 6 Mar 2004 00:37:44
Message: <404963a8@news.povray.org>
Jim Charter <jrc### [at] msncom> wrote in message
news:40479763@news.povray.org...
<snip>
> With the recent boom in
> the availability of mesh (polygonal) modellers in the
> freeware/shareware/hobbiest space, more and more POVers seem to be
> embracing mesh modelling as an creative tool.
>
> What are peoples' thoughts on this.  Who are beginning to experiment
> with mesh tools and what tools are you using?  How do you see them
> fitting in with your style and expressive intentions?

For me two things heavily define my tools.  The first is cost.  I have very
limited funds to spend on a hobby, so any tool I can get free is a good
tool.  I do have Bryce and Poser, but only because someone gave them to me
as gifts a few years ago.  I will also pay for inexpensive shareware
programs if I find them useful enough, but that is usually limited to the
under $25 - $30 range.  I may extend that range and register Terragen since
even though I find it fairly useless for creating heightfields, it does such
great skies that I keep finding myself going back to it just for the sky.

The second thing is workflow.  Anything that speeds up the process is good.
I was pretty good with Hamapatch, but only for certain things.  I tried
Wings3d sometime ago, but didn't like it because I was trying to do the same
things I did in Hamapatch, and they simply didn't work as well.  But having
just spent the last IRTC round actually learning Wings3d, I am quite
impressed with how quickly I can create good models. I will definitely be
using it a lot more in the future.

Back to your original question specifically regarding mesh tools, they're
great!  I am not mathmatically inclined, so building meshes in POV is pretty
much an exercise in frustration.  While there is a lot that can be done in
POV with CSG, prisms, lathes and sphere_sweeps, some things just require the
ability to work with a model in a more interactive and intuitive way, and
mesh tools provide that.  You can't take a CSG shape and bend it just to see
what it looks like.  In both Hamapatch and Wings, I'm free to experiment
with my shapes and change them on the fly.  That leads to new ideas and
often produces something that I would simply never be able to produce using
SDL.

Blender has some interesting and powerful modeling tools also, but I have
been put off in the past by it's non-friendly interface.  I see that since
it's gone open-source it has changed a lot, so I'll be giving it another try
again soon.  (Well, if I can ever get linux running on this machine
   otherwise it will have to wait til spring when I get another box...)


> Further, commercial software producers seem to understand the role of
> the amateur market in creating a workerpool with software skills.  So
> marketshare there can influence marketshare in the commercial venue.
> This has lead to highend vendors making training versions of these
> powerful products available to the hobbiest community.

Key word "training versions"...  I haven't noticed that the commercial
products are being marketed to hobbyists so much as they are trying to lure
CG students into spending the big bucks on a full version.  And student
versions are still out of my price range, at least the good ones like 3DS &
Maya.  The free versions of lesser apps like Truespace are crap IMO, awkward
interfaces and crippled features that have you running back to POV in short
order.


> What role does this leave for POV?

POV is a whole different approach to CG as far as I can tell.   While some
of the high end apps have scripting languages built in to do some of the
things POV does, the bottom line is the SDL gives a flexibility that a
strictly mesh based app just doesn't have.  As long as that is true, POV
will have it's own niche.  It certainly has more geek appeal.  I constantly
see posts about different kinds of optical projects or scientific
visualizations people are trying to work POV into, and I don't think even
the high end apps can do some of that stuff, again because of the
flexibility of SDL.  And you'll never see a short code contest in 3DS, I
guarantee it.

Plus, POV forces you to actually learn what you're doing, since you have to
code it all yourself.  Since I started using POV, my Bryce images have
gotten a lot better because now I actually know what some of those buttons
and sliders do.  One of the first things POVers taught me was "ambient 0".
Going back to Bryce's texture editor and looking at the defaults for its
textures, most of them default to the equivilent of "ambient .28".  No
wonder I could never get decent looking lighting and shadows!  I have since
gone back and completely redone all the textures in several of my Bryce
scenes.

RG


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From: Warp
Subject: Re: Mesh etc.
Date: 6 Mar 2004 04:34:39
Message: <40499b2f@news.povray.org>
Gilles Tran <tra### [at] inapginrafr> wrote:
> You forgot uv-mapping which offers uv-mapping on meshes for the masses

  But it still isn't a feature exclusive to mesh2. You can use UV-mapping
with mesh as well.
  mesh2 is simply an alternative syntax to mesh, that's it.

  UV-mapping was added as a very requested new property of the internal
mesh primitive, but it's nothing exclusive to the mesh2 syntax.

>, and
> it certainly made a big difference. I'm aware that uv-mapping is somehow
> feasible with a union of triangles

  I was not comparing mesh2 with a union of triangles. I was comparing
mesh2 with mesh.
  The original claim was that mesh2 was added for greater compatibility.
No, it was added as an alternative, more efficient syntax for an
already-existing primitive: mesh.
  It's true that UV-mapping was added at the same time as this alternative
syntax, but it still isn't something exclusive to mesh2.

> Also, I wouldn't play down the smaller size advantage.

  I'm not belittling that. I'm saying it was the main reason for the mesh2
syntax.

> So, from a user's standpoint, mesh2 is
> certainly a new feature, since it allows things that were difficult or
> impossible to do without it.

  Is there something which is impossible to achieve with a mesh and which
is possible with a mesh2?

  mesh2 is a new feature, but it's a new *syntax* feature, not a new
primitive. mesh2 didn't add anything POV-Ray couldn't already do.

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -


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From: Warp
Subject: Re: Mesh etc.
Date: 6 Mar 2004 04:39:12
Message: <40499c40@news.povray.org>
ingo <ing### [at] tagpovrayorg> wrote:
> For me an interseting thing with mesh2 is that it is easier to create 
> complex mesh' by using macros within POV-Ray SDL.

  That's curious.
  Every time I create a mesh algorithmically with POV-Ray SDL I find it
much easier to create it with the 'mesh' syntax and much harder with
the 'mesh2' syntax. That's because with 'mesh' you can just create
the triangles and that's it. With 'mesh2' you need to create quite
lot more (basically you need to create all the unique vertex points
and then create index values to them in order to create your triangles).

  The mesh2 syntax is more compact and efficient, but when you are
creating triangles algorithmically it makes it a lot more complicated
to do it the mesh2-way. Creating triangles the mesh-way is easier
(even though not so efficient parsing-speed-wise, of course).

  There are, of course, cases where doing it the mesh2-way is easier,
but in my personal experience rarely.

-- 
plane{-x+y,-1pigment{bozo color_map{[0rgb x][1rgb x+y]}turbulence 1}}
sphere{0,2pigment{rgbt 1}interior{media{emission 1density{spherical
density_map{[0rgb 0][.5rgb<1,.5>][1rgb 1]}turbulence.9}}}scale
<1,1,3>hollow}text{ttf"timrom""Warp".1,0translate<-1,-.1,2>}//  - Warp -


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From: Gilles Tran
Subject: Re: Mesh etc.
Date: 6 Mar 2004 06:22:38
Message: <4049b47e@news.povray.org>

news:40499b2f@news.povray.org...
>   UV-mapping was added as a very requested new property of the internal
> mesh primitive, but it's nothing exclusive to the mesh2 syntax.

Well yes, it's not exclusive. In fact, by looking to my scene files I
realise that my first uv-mapped meshes were actually mesh{} with uv vectors
attached (in 1999). However, the few tools that supported it were faulty and
dropped from sight, so for a while the only converter that supported
uv-mapping was 3DWin, which only writes uv-mapped mesh2{} (and non-uv mapped
mesh{}). Poseray now supports uv-mapping for both mesh and mesh2, but since
having uv-mapped mesh{} makes little sense (for converted models) it's no
wonder that mesh2 is perceived like the definitive mesh format.

>  Is there something which is impossible to achieve with a mesh and which
>  is possible with a mesh2?

Depends on your definition of "impossible" ;-) Stricly speaking, we can
conclude that mesh and mesh2 are equivalent, but in the real world things
are just more complicated. I just ran a test on Poseray and the uv-mapped
mesh{} equivalent of a uv-mapped mesh2{} is 2.6 time bigger. For a given
amount of resource (disc space, patience...) you can do things with mesh2
you cannot do with mesh. They're not theoretically impossible, for for all
practical purpose, they are. For instance, I'm prepared to handle a 100 Mb
mesh but not a 260 Mb one because I'd run out of time and patience. Also,
I'll be able to put a good number of mesh2{} objects for download on my
website without having to buy extra space...

G.

-- 
**********************
http://www.oyonale.com
**********************
- Graphic experiments
- POV-Ray and Poser computer images
- Posters


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From: Tom Galvin
Subject: Re: Mesh etc.
Date: 6 Mar 2004 11:48:29
Message: <Xns94A4781ED35AFtomatimporg@203.29.75.35>
"gonzo" <rgo### [at] lansetcom> wrote in news:404963a8@news.povray.org:


> 
> Blender has some interesting and powerful modeling tools also, but I
> have been put off in the past by it's non-friendly interface.  I see
> that since it's gone open-source it has changed a lot, so I'll be
> giving it another try again soon.  (Well, if I can ever get linux
> running on this machine otherwise it will have to wait til spring 
> when I get another box...) 
> 
> 

Blender is available for Windows, Mac OS X, Linux, Solaris ....

http://www.blender3d.org/Download/

-- 
Tom
_________________________________
The Internet Movie Project
http://www.imp.org/


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