When generating animations, it's extremely helpful to be able
to render a very fast, very low-quality version of the images
to check for object motion and the like. I know thatPOV-Ray
has the Q switch to lower quality by removing expensive
calculations, but I'd like to see a mode where it just
renders wireframes of the objects involved. This would probably
be even faster and would serve the purpose. Perhaps the +Q0
setting (which is already a duplicate of +Q1) could be re-
defined to turn on wireframe display.

If this is not already under consideration for the next version
of POV-Ray, I'd like to suggest that it be considered for
inclusion in the next version. Thanks.

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Steve Martin wrote:

> If this is not already under consideration for the next version
> of POV-Ray, I'd like to suggest that it be considered for
> inclusion in the next version. Thanks.

This subject comes up from time to time and it is considered not something
that would be easy to implement because of the way objects are represented
internaly in the rendering engine - rather they are not represented at all
since they are mostly mathematical constructs that are rendered to screen.
As I understand it about the only Pov primitives that it would be possible
with would be bicubic patches, height fields, and triangle meshes. To make
this possible in POV-Ray for all objects you would have to add the ability
to intenaly represent all objects as a triangle mesh object.  POV-Ray is a
rendering program and not a modelling program.

-- 
Wishing you Seasons Greetings and A Happy New Millennium !
Ken Tyler -  1300+ Povray, Graphics, 3D Rendering, and Raytracing Links:
http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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In article <38676743.40549E0C@usit.net>, sma### [at] usitnet wrote:

> When generating animations, it's extremely helpful to be able
> to render a very fast, very low-quality version of the images
> to check for object motion and the like. I know thatPOV-Ray
> has the Q switch to lower quality by removing expensive
> calculations, but I'd like to see a mode where it just
> renders wireframes of the objects involved. This would probably
> be even faster and would serve the purpose. Perhaps the +Q0
> setting (which is already a duplicate of +Q1) could be re-
> defined to turn on wireframe display.

Well, because POV renders mathematical shapes instead of meshes, this 
would not be easy. How would you reduce a julia fractal to a wireframe? 
Or an isosurface? You would have to add code for every shape, and this 
would also make adding new shapes harder. And from what I have heard, 
the CSG code for the wireframe will be much more difficult to write.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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Steve Martin wrote:
> 
> When generating animations, it's extremely helpful to be able
> to render a very fast, very low-quality version of the images
> to check for object motion and the like. I know thatPOV-Ray
> has the Q switch to lower quality by removing expensive
> calculations, but I'd like to see a mode where it just
> renders wireframes of the objects involved. This would probably
> be even faster and would serve the purpose. Perhaps the +Q0
> setting (which is already a duplicate of +Q1) could be re-
> defined to turn on wireframe display.

Agreeing with the other comments about wireframe-is-difficult,
i structure my code with conditionals to speed up renders.
Like i have a Christmas Tree which can be rendered as a single cone
rather than 90000 objects.

http://www.buckosoft.com/office/cvsweb/pov/cvsweb.cgi/tteoac/ctree.inc?rev=1.1&content-type=text/x-cvsweb-markup
See #if (UseRealTree) and #if (UseFakeTree)

You could do the same thing.  Choose either a monopigment cube or sphere depending
on the "real" shape of the complex object and use that for checking motion
for your real objects.

dik

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> calculations, but I'd like to see a mode where it just
> renders wireframes of the objects involved.

Thanks to everyone who responded to the above. It appears
that I was laboring under misinformation, that POV-Ray
breaks objects down into triangles before it renders.
If that were true, it would in fact probably (at least
it seems to me) be easier to render the wireframes than
it would be to render the shaded triangles; just draw
the edges with solid lines. However, my information
being obviously incorrect, I concur that this would be
something that would be unworkable to implement.

Back to the drawing board...

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Steve Martin <sma### [at] usitnet> wrote:
: Thanks to everyone who responded to the above. It appears
: that I was laboring under misinformation, that POV-Ray
: breaks objects down into triangles before it renders.

  Of course this is not so. If it were, there would be, of course, some
method to specify the quality of the triangulation, etc (like with
bezier patches).
  For some objects triangulation is impossible, for example the paraboloid
or the hyperboloid quadrics. (It's impossible because the area of these
surfaces is infinite.)

  What povray (and almost every raytracer) does is to mathematically
calculate the intersection of a line and the object in question (which
is only represented as a mathematical entity, not as a true object).

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Q0 has always been adequate for me

Chris Huff wrote:

> In article <38676743.40549E0C@usit.net>, sma### [at] usitnet wrote:
>
> > When generating animations, it's extremely helpful to be able
> > to render a very fast, very low-quality version of the images
> > to check for object motion and the like. I know thatPOV-Ray
> > has the Q switch to lower quality by removing expensive
> > calculations, but I'd like to see a mode where it just
> > renders wireframes of the objects involved. This would probably
> > be even faster and would serve the purpose. Perhaps the +Q0
> > setting (which is already a duplicate of +Q1) could be re-
> > defined to turn on wireframe display.
>
> Well, because POV renders mathematical shapes instead of meshes, this
> would not be easy. How would you reduce a julia fractal to a wireframe?
> Or an isosurface? You would have to add code for every shape, and this
> would also make adding new shapes harder. And from what I have heard,
> the CSG code for the wireframe will be much more difficult to write.
>
> --
> Chris Huff
> e-mail: chr### [at] yahoocom
> Web page: http://chrishuff.dhs.org/

--
Bryan Valencia
Software Services - Making Windows Scream
http://www.209software.com
mailto:bry### [at] 209softwarecom

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I seldom use the +Q switch. I always use the +SP switch.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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