Warp <war### [at] tagpovrayorg> wrote in news:3d7a59f0@news.povray.org

>   To get environment mapping, make a sky_sphere with your map (which
>   could 
> be generated by rendering a scene with a spherical camera or whatever)
> as as spherical map and simply make your object reflective. If there
> are no other objects in the scene, you'll get exactly the same
> environment mapping as in scanline renderers (if there are other
> objects, they will be reflected as well, unless they have
> no_reflection defined). 

no - this will work only for convex shapes like sphere, box
other shapes will reflect they selfs (and their should reflect ONLY 
sky_sphere)

This, and other effects will be trivial to make in SDL if only :
- functions will be allowed to work on <x,y,z> AND <xn,yn,zn> normals
- we can load image into array and access it from function
realy nobody will like this future :) it gives so many possibilites...

> Of course the advantage of doing this is debatable.

with with argument You do not agree :

- allow to have POV scenes acting _same_ as in some other renderers 
(sometimes POV is working too good - almost every other future can be 
turned off, instead of this)
- it saves time (in heave reflection secenes)
- can be used in some artistics effects

-- 
#macro g(U,V)(.4*abs(sin(9*sqrt(pow(x-U,2)+pow(y-V,2))))*pow(1-min(1,(sqrt(
pow(x-U,2)+pow(y-V,2))*.3)),2)+.9)#end#macro p(c)#if(c>1)#local l=mod(c,100
);g(2*div(l,10)-8,2*mod(l,10)-8)*p(div(c,100))#else 1#end#end light_source{
y 2}sphere{z*20 9pigment{function{p(26252423)*p(36455644)*p(66656463)}}}//M

Post a reply to this message

> no - this will work only for convex shapes like sphere, box
> other shapes will reflect they selfs (and their should reflect ONLY
> sky_sphere)
not if you add no_reflection to the reflecting objects.

cu!
--
ZK AKA SaD
http://www.povplace.be.tf
"Don't think you are. *Know* you are!"

Post a reply to this message

see image in p.b.i

cu!
--
ZK AKA SaD
http://www.povplace.be.tf
"He can breathe OK, long as nobody unplugs him"

Post a reply to this message

"Christoph Hormann" <chr### [at] gmxde> wrote in message
news:3D79EB22.B5958C53@gmx.de...
> You just should notice that refusing to take some care about correct
> typing clearly shows disrespect towards the readers of the posting.
>


    Don't forget that for quite a large proportion of people reading and
posting here English _is not_ their native language and may well be using
non-English OS's - being picky about a few minor errors in their posts
clearly shows disrespect towards these people - and quite frankly,
Christoph, I would have thought you would be one of the more forgiving
people in this respect...

--
Pandora/Scott Hill/[::O:M:C::]Scorpion
Software Engineer.
http://www.pandora-software.com

Post a reply to this message

On Sun, 8 Sep 2002 01:43:09 +0100, "Pandora"
<pan### [at] pandora-softwarecom> wrote:

>    Don't forget that for quite a large proportion of people reading and
>posting here English _is not_ their native language and may well be using
>non-English OS's - being picky about a few minor errors in their posts
>clearly shows disrespect towards these people - and quite frankly,
>Christoph, I would have thought you would be one of the more forgiving
>people in this respect...

Well, Scott, I am not a native speaker, and I am not using an English
OS nor the keyboard layout I am used to. In fact, the OS and software
I use are almost without exception in a language I don't know, German.
I still care to run my posts through a spell-checker nonetheless. I am
not saying that I have to, or even that I should, only that I do.
Neither am I obliged to shave every morning before I go to work, but I
do so anyway. Nor is anyone making me call my boss (with whom we are
good friends) "Sir" when there are guests at the office. It all comes
down to respect and/or sloppiness.


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

Post a reply to this message

"Zeger Knaepen" <zeg### [at] studentkuleuvenacbe> wrote in 
news:3d7a8574@news.povray.org

> see image in p.b.i

solutnion #1 with no_reflection would be perfect, UNLESS :

A - object with no_reflection
B,C - standart objects with standart pov's relfection { }

now :
+ A will reflect sky-sphere and will look like with env_mapping
+ A will NOT reflect itself (if it is a complex shape)
+ B will relfect C (and vice-versa)
+ B and C will reflect A

but:
- A will reflect not only sky, but alsow B and C objects.

I know that the last effect is photo-realistic, but it disallow some 
artistics effects (and speed improvment)

-- 
#macro g(U,V)(.4*abs(sin(9*sqrt(pow(x-U,2)+pow(y-V,2))))*pow(1-min(1,(sqrt(
pow(x-U,2)+pow(y-V,2))*.3)),2)+.9)#end#macro p(c)#if(c>1)#local l=mod(c,100
);g(2*div(l,10)-8,2*mod(l,10)-8)*p(div(c,100))#else 1#end#end light_source{
y 2}sphere{z*20 9pigment{function{p(26252423)*p(36455644)*p(66656463)}}}//M

Post a reply to this message

"Rafal 'Raf256' Maj" <raf### [at] raf256com> schreef in bericht
news:Xns### [at] 204213191226...
> solutnion #1 with no_reflection would be perfect, UNLESS :
> A - object with no_reflection
> B,C - standart objects with standart pov's relfection { }
> now :
> + A will reflect sky-sphere and will look like with env_mapping
> + A will NOT reflect itself (if it is a complex shape)
> + B will relfect C (and vice-versa)
> + B and C will reflect A
> but:
> - A will reflect not only sky, but alsow B and C objects.
> I know that the last effect is photo-realistic, but it disallow some
> artistics effects (and speed improvment)
Oh, I see... You want pure environment_mapping for 1 object and real
reflection for another object?
Hmmm, I don't reall think that's possible, unless you're happy with Gilles
Tran's solution (which might indeed give nice effects in some cases).

cu!
--
ZK AKA SaD
http://www.povplace.be.tf
"Don't think you are. *Know* you are!"

Post a reply to this message

"Zeger Knaepen" <zeg### [at] studentkuleuvenacbe> wrote in
news:3d7b344a$1@news.povray.org 

> Oh, I see... You want pure environment_mapping for 1 object and real
> reflection for another object?
> Hmmm, I don't reall think that's possible, unless you're happy with
> Gilles Tran's solution (which might indeed give nice effects in some
> cases). 

or unless this future-requst will be used in pov 3.6 / 4 :)

-- 
#macro g(U,V)(.4*abs(sin(9*sqrt(pow(x-U,2)+pow(y-V,2))))*pow(1-min(1,(sqrt(
pow(x-U,2)+pow(y-V,2))*.3)),2)+.9)#end#macro p(c)#if(c>1)#local l=mod(c,100
);g(2*div(l,10)-8,2*mod(l,10)-8)*p(div(c,100))#else 1#end#end light_source{
y 2}sphere{z*20 9pigment{function{p(26252423)*p(36455644)*p(66656463)}}}//M

Post a reply to this message

Rafal 'Raf256' Maj <raf### [at] raf256com> wrote:
> no - this will work only for convex shapes like sphere, box
> other shapes will reflect they selfs (and their should reflect ONLY 
> sky_sphere)

  So what? The better it looks. I can't think of any reason of wanting
it to look unrealistic.
  Besides, as already suggested, no_reflection can achieve this.

> with with argument You do not agree :

> - allow to have POV scenes acting _same_ as in some other renderers 

  But why would you want to?
  Scanline renderers can't calculate reflections for curved surfaces (without
using raytracing). In order to relieve this problem a more limited trick
was developed: Environment mapping. This simulates reflection if the map
is properly done and the other objects in the scene it "reflects" are not
too close to this one (if they are, the reflections get distorted in an
unrealistic way). It's also impossible to make self-reflection with this
trick. Another problem with environment mapping is the introduced resolution
limit of the map.
  That is, it's a trick which simulates reflection, and it does an acceptable
job only in certain cases, while there are cases where it does a very poor
job.

  In raytracing you don't *need* to resort to this kind of trick, as you
have a very easy way of getting a perfect reflection.
  Why would you want to degrade POV-Ray and introduce a cheap trick which
doesn't even work very well? Reflection is one of the strongest features
of a raytracer. Adding a worse trick makes no sense.

> - it saves time (in heave reflection secenes)

  Heavy reflection scenes have many inter-reflecting and self-reflecting
objects. Environment mapping simply does not work with this.
  Setting max_trace_level to 2 gives you a very similar result as
environment mapping and it shouldn't even be radically slower (in fact,
it could even be faster in many cases).
  Besides, environment maps consume lots of memory. You need pretty high
resolution maps if you want to avoid pixelation.

> - can be used in some artistics effects

  IMHO that's not reason enough to add such feature.

-- 
#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 -

Post a reply to this message

Rafal 'Raf256' Maj <raf### [at] raf256com> wrote:
> but:
> - A will reflect not only sky, but alsow B and C objects.

  And this is bad because...?

-- 
#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 -

Post a reply to this message