On the other hand... How many times have you used a transformed plane?-)

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

Post a reply to this message

Peter Popov <pet### [at] usanet> wrote:
: Can a similar approach be taken for triangles?

  Why not? Transforming a triangle results in another triangle. The
transformation could be done by changing the vertices of the triangles at
parse time.

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

Post a reply to this message

Warp wrote:
> 
>   On the other hand... How many times have you used a transformed plane?-)
> 

Is a rotated plane a transformed plane ???

If so, the answer is:
Many, in CSG difference or intersection...

Bouf.

Post a reply to this message

Bouf <Chr### [at] nanterremarellifr> wrote:
: Is a rotated plane a transformed plane ???

  Yes.

: If so, the answer is:
: Many, in CSG difference or intersection...

  Perhaps. I usually use a box, though.

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

Post a reply to this message

[Warp <war### [at] tagpovrayorg>]
|   Perhaps. I usually use a box, though.

A box could be implemented as a test on 3 pairs of planes.
Anyone here know how POV-Ray implements it? 

-- 
A penny for your thoughts.
Mine are more expensive.

Post a reply to this message

POVray team HAVE my permission for all my POV patch to:
 - add in POV ray tracer.
 -  modify. Bug killing, comments adding, etc.
 - and other necessary thigs which makes povray.exe better.

TonyB <ben### [at] panamac-comnet> wrote in message
news:38f69fd4@news.povray.org...
> >Hard telling.  There's the matter of getting permission from the
> >author, for one thing.  There's also the matter of my sig, which
> >I seem to have misplaced.  I don't speak for the POV-Team.
>
>
> I never said anything about your sig. I just know that if something better
> is out there, then it should become official. (With the author's
permission,
> of course, although I don't know why an author wouldn't want his work to
> enter the official version.)
>
>

Post a reply to this message

Peter Popov <pet### [at] usanet> wrote in message
news:fifcfs8diqum0iapiudcvp7j762sm9mup5@4ax.com...
> On Thu, 13 Apr 2000 14:28:15 +0200, "Dejan D. M. Milosavljevic"
> <dmi### [at] xoommailcom> wrote:
>
> >Entire source and test scenes at  -- Plane patch --  page  via
> >http://members.xoom.com/dmilos/prg/pov/mypovpage.htm
>
> <snip>
>
> >Any comment?!
>
> Yes. I am not a programmer, but I must tell you I really respect your
> work with these patches. Correct me if I'm wrong in thinking that the
> real art of it seems to be in finding the right spot to correct and
> then leaving everyone else slapping their foreheads asking themselves
> how they haven't thought of that first :)
>

I have few theory.
1.One of  programming's  rule said :   if ( work_properly() )
 do_not_touch(); }.
2. Many people see that. Doubtlessly. But they think there is no need to do
it.


> This plane patch is a really nifty one (now that Ron has explained
> what you've done). Can a similar approach be taken for triangles? IIRC
> the intersection point of the test ray and the plane of the triangle
> is tested for insidedness using a lemma of one of Jordan's theorems.
> This requires several steps of manipulating 3D vectors. Maybe if one
> of the coordinates is stripped down (the triangle and intersection
> point are projected on a coordinate plane), these calculations would
> only require 2D vectors. Of course the right projecting plane should
> be chosen.
>
> What do you think? Is it worth the trouble?
>

Triangle is one of the most investigated primitive.
For ray tracer version with 2D vector is one of  the best in theory.
In a real life we have specialized processors and question: "How to use
their ability".

>
> Peter Popov ICQ : 15002700
> Personal e-mail : pet### [at] usanet
> TAG      e-mail : pet### [at] tagpovrayorg

Post a reply to this message

On 14 Apr 2000 03:21:39 -0400, Warp wrote:
>  On the other hand... How many times have you used a transformed plane?-)

I use them a lot for clipping.

-- 
Ron Parker   http://www2.fwi.com/~parkerr/traces.html
These are my opinions.  I do NOT speak for the POV-Team.

Post a reply to this message

Dejan D. M. Milosavljevic <dmi### [at] xoommailcom> wrote...
> Entire source and test scenes at  -- Plane patch --  page  via
> http://members.xoom.com/dmilos/prg/pov/mypovpage.htm
>

This is a great patch and will be included in MegaPov 0.5 (unless Dejan
doesn't want it to be).  :-)

-Nathan

Post a reply to this message

Include granted!

Go and get it!

http://members.xoom.com/dmilos/prg/pov/plane/plane.zip


Nathan Kopp <Nat### [at] Koppcom> wrote in message
news:38f718e2$1@news.povray.org...
>
> Dejan D. M. Milosavljevic <dmi### [at] xoommailcom> wrote...
> > Entire source and test scenes at  -- Plane patch --  page  via
> > http://members.xoom.com/dmilos/prg/pov/mypovpage.htm
> >
>
> This is a great patch and will be included in MegaPov 0.5 (unless Dejan
> doesn't want it to be).  :-)
>
> -Nathan
>
>

Post a reply to this message