Scannng a page from the National Geographic
does not count as ray-tracing ;)

IMHO lose the bubbles or fix them completely.
they look "cartoon-like" and ruin your beautiful picture.

"Chris S." <chr### [at] bluelectrodecom> wrote in message
news:39838531@news.povray.org...
> Similar scene from my previous post with isosurface boulders.
> Comments/suggestions welcome.
>
> -Chris-
>
>
>

Post a reply to this message

"ryan constantine" <rco### [at] yahoocom> wrote :
>
> aren't round?  where do you get your bubbles?

    I get mine in the swimming pool and unless they are so small that
surface tension is the only significant force, 1/2 inch or smaller, they
distort heavily because of their travel through the water. They look like a
mushroom or a jelly fish.

    Here is a photo from my Aquarium.

Post a reply to this message

Attachments:
Download 'Bubb02.jpg' (24 KB)

Preview of image 'Bubb02.jpg'

Actually I agree with Bill DeWitt if you ever look at pictures of bubbles rising
to the surface from scuba divers they look flattened out, more like jelly fish as
Bill said.

ryan constantine wrote:

> > Bubbles aren't round
> > (they look more like jelly fishes as the rise) and they might ought to be a
> > little clearer.
>
> aren't round?  where do you get your bubbles?  mine are round.  i
> checked in the bathtub today :)  just kidding.  but seriously, the real
> problem is that bubbles group together, keeping individual membranes,
> but travelling together and touching each other.  but they will always
> try to destroy those membranes and make one bubble.  an individual
> bubble will always be a near perfect sphere (slightly distorted in the
> direction of travel) because that is the most compact shape the pressure
> inside (air) can exert on the pressure outside (water).  so keep them
> round, sort of.
>
> i agree on the color thing.  they should be clear.

--
Come visit my web site:-) : http://www.geocities.com/~thomaslake/

Post a reply to this message

"Chris S." wrote:
> 
> Similar scene from my previous post with isosurface boulders.
> Comments/suggestions welcome.

Very convincing rocks! But those bubbles gotta go...

-Xplo

Post a reply to this message

On Sat, 29 Jul 2000 21:20:07 -0700, "Chris S."
<chr### [at] bluelectrodecom> wrote:

>Similar scene from my previous post with isosurface boulders.
>Comments/suggestions welcome.

Comments? You already know about the bubbles :)

Suggestions? Let some sunrays filter through the water making
beautiful speckles on the sea floor and a spectacle of light in the
water itself. That would require photons and media, hmm, and maybe a
Cray, but hey, it would be worth the wait I am certain.


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

Post a reply to this message

"Chris S." wrote:
> 
> Similar scene from my previous post with isosurface boulders.
> Comments/suggestions welcome.
> 

Looks great, very realistic.  What pattern do you use for the roughtness of the
surface ? Is it only noise3d or some pigment ?

There are two light and flat parts in the dark areas on the right, one not much
visible on the left, not sure what it is, but it looks somewhat wrong.  

Christoph

--
Christoph Hormann <chr### [at] gmxde>
Homepage: http://www.schunter.etc.tu-bs.de/~chris/

Post a reply to this message

Xplo Eristotle <inq### [at] unforgettablecom> wrote in message
news:3983B7DD.7B52B225@unforgettable.com...
>
>
> "Chris S." wrote:
> >
> > Similar scene from my previous post with isosurface boulders.
> > Comments/suggestions welcome.
>
> Very convincing rocks! But those bubbles gotta go...
>
> -Xplo

Wow, my bubbles are really getting trashed!  However, I agree with previous
comments that they should be whiter and more organically shaped...but
therein lies the problem.  The bubbles themselves are clear and would be
invisible if not for a .25 reflective finish.  I suppose I could try a blob
macro on the bubbles, but common, get rid of the bubbles!?...how can you say
no to bubbles;)

-Chris-

Post a reply to this message

Christoph Hormann <Chr### [at] schunteretctu-bsde> wrote in message
news:3983CBBE.C4240AFD@schunter.etc.tu-bs.de...
> Looks great, very realistic.  What pattern do you use for the roughtness
of the
> surface ? Is it only noise3d or some pigment ?

Thanks.  The texture is a rather simple bozo with a highly turbulence
normal.  The rock itself is a bloby isosurface eaten away by a "big"
noise3d, creating basic shape, and a "small" noise3d, giving the rock pits
and bumbs.

> There are two light and flat parts in the dark areas on the right, one not
much
> visible on the left, not sure what it is, but it looks somewhat wrong.

That's an area where the rock has been completely eaten through by the
noise3d, so you're able to see another rock, which has become more faded due
to fog.

Post a reply to this message

In article <3984314f$1@news.povray.org>, "Chris S." 
<chr### [at] bluelectrodecom> wrote:

> Wow, my bubbles are really getting trashed!  However, I agree with 
> previous comments that they should be whiter and more organically 
> shaped...but therein lies the problem.  The bubbles themselves are 
> clear and would be invisible if not for a .25 reflective finish. 

Ah, here is one problem. Use angle-dependant reflection, some 
refraction(ior 0.67? Or just ior 1, and difference the bubbles away from 
your water object, which should be around ior 1.33), and very small 
specular highlights.


> I suppose I could try a blob macro on the bubbles,

For the largest bubbles a blob macro would help, but for the 
medium-sized ones, an asymmetrically scaled sphere would work. To do 
this, just sandwich together a hemisphere and a sphere with different 
scales, and use merge to remove the interior surfaces. Something like 
this:

merge {
    difference {
        sphere {< 0, 0, 0>, 1}
        plane {y, 0}
    }
    sphere {< 0, 0, 0>, 1 scale < 1, 0.5, 1>}
} 

Or you should be able to get some interesting isosurface bubbles...

-- 
Christopher James Huff - Personal e-mail: chr### [at] maccom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://homepage.mac.com/chrishuff/
TAG Web page: http://tag.povray.org/

Post a reply to this message

"Chris S." <chr### [at] bluelectrodecom> wrote :
>
> Wow, my bubbles are really getting trashed!

    This group is  known for our unreasoned hatred for bubbles.

> However, I agree with previous
> comments that they should be whiter and more organically shaped...but
> therein lies the problem.  The bubbles themselves are clear and would be
> invisible if not for a .25 reflective finish.  I suppose I could try a
blob
> macro on the bubbles, but common, get rid of the bubbles!?...how can you
say
> no to bubbles;)

    I would go with blobs and interior, making the ior of the bubbles less
than the ior of the water. You want refraction, not reflection.

Post a reply to this message