"Chris Huff" wrote:
> It *is* possible to have displacement be independant of
> gradient... just displace the coordinates you give to the
> blob function, instead of adding to/subtracting from the
> function.

Aha, I didn't know that.

> Use 3 displacement functions with outputs from -1 to 1,
> each one offset a bit so it doesn't synchronize with the
> others

It sounds to me like a displacement pattern value will displace the surface
in a specific direction rather than displacing it in the direction of the
surface normal (or vnormalized gradient vector). That makes me think that it
is not useful for displacing a surface by a specific and detailed 3D solid
pattern. Is that correct? Maybe there's another method for handling this?

Rune
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In article <3a9ecbf4@news.povray.org>, "Rune" <run### [at] inamecom> 
wrote:

> It sounds to me like a displacement pattern value will displace the 
> surface in a specific direction rather than displacing it in the 
> direction of the surface normal (or vnormalized gradient vector). 
> That makes me think that it is not useful for displacing a surface by 
> a specific and detailed 3D solid pattern. Is that correct? Maybe 
> there's another method for handling this?

Correct, it works more like the first type of displace warp (which 
actually may be a more efficient way of doing it...), pushing the 
surface in a direction depending only on it's position.
I'm not sure what you mean by "displacing a surface by a specific and 
detailed 3D solid pattern", could you explain what you want?

Maybe another type of displace warp, using the gradient to determine the 
direction of displacement, and another pattern to define the amount of 
displacement. Also, the ability to use a spline as a "float_map" instead 
of a pigment.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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Chris Huff wrote:
> 
> Maybe another type of displace warp, using the gradient to determine the
> direction of displacement, and another pattern to define the amount of
> displacement. 

I think that could approximately be done by using a pigment_map
construction or a function pigment combining both patterns, not totally
sure about it though.

> Also, the ability to use a spline as a "float_map" instead
> of a pigment.

Could you explain more detailed?

Christoph

-- 
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other 
things on: http://www.schunter.etc.tu-bs.de/~chris/

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In article <3A9F5FAB.EC816B6E@gmx.de>, Christoph Hormann 
<chr### [at] gmxde> wrote:

> I think that could approximately be done by using a pigment_map
> construction or a function pigment combining both patterns, not totally
> sure about it though.

I don't think so...well, you could do it all by hand, but it would be 
extremely tedious, even using the blob_pigment feature. A modification 
of the displace warp would be faster and tremendously easier.


> > Also, the ability to use a spline as a "float_map" instead
> > of a pigment.
> 
> Could you explain more detailed?

The displace warp uses the gradient of the grayscale value of the color 
of a pigment to determine the direction and amount of warping to do. 
Instead of taking a pigment (pattern + color_map), it will be able to 
take a pattern and spline, and get the float value directly instead of 
converting colors to floats. In other words, using a spline {} as a 
"float_map {}", mapping float values to pattern values.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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Chris Huff wrote:
> 
> The displace warp uses the gradient of the grayscale value of the color
> of a pigment to determine the direction and amount of warping to do.
> Instead of taking a pigment (pattern + color_map), it will be able to
> take a pattern and spline, and get the float value directly instead of
> converting colors to floats. In other words, using a spline {} as a
> "float_map {}", mapping float values to pattern values.
> 

Wouldn't a spline wavetype for patterns do that?

Christoph

-- 
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other 
things on: http://www.schunter.etc.tu-bs.de/~chris/

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In article <3A9F97C4.1DEE44C9@gmx.de>, Christoph Hormann 
<chr### [at] gmxde> wrote:

> Wouldn't a spline wavetype for patterns do that?

Right, you won't need separate patterns and splines, it would work just 
fine using a pattern with a spline_wave waveform. I should have thought 
of that, I *wrote* the patch!

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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"Chris Huff" wrote:
> I'm not sure what you mean by "displacing a surface by
> a specific and detailed 3D solid pattern", could you
> explain what you want?

> Maybe another type of displace warp, using the gradient
> to determine the direction of displacement, and another
> pattern to define the amount of displacement.

I think so.

I want the function A to be displaced by the vector V according to the
pattern B. The direction (but not the length) of vector V is determined by
the gradient of function A (before displacement). The length of vector V is
determined by the value of pattern B.

As you can imagine, this will have an effect much like normals, except that
it isn't faked.

Rune
--
\ Include files, tutorials, 3D images, raytracing jokes,
/ The POV Desktop Theme, and The POV-Ray Logo Contest can
\ all be found at http://rsj.mobilixnet.dk (updated January 28)
/ Also visit http://www.povrayusers.org

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Rune <run### [at] inamecom> wrote in message
news:3a9abd33@news.povray.org...
> "Margus Ramst" wrote:
> > Whoa, I had to look twice to make sure you weren't BS-ing
> > us with a photo - in fact I'm still a bit suspicious :)
>
> Any particular thing that gives away that it isn't a photo?

Well to me most cgg stuff looks like clay anyway for some reason. I'm not
sure exactly what (probably the lighting and shadows like the others have
said) but something about it just says computer generated. (I've been
looking at cgg images too long probably and have learned to tell what to
look for ^_^)

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Rune <run### [at] inamecom> wrote in message
news:3a9bffdf$1@news.povray.org...
> "Christoph Hormann" wrote:
> > Very realistic, i would really try radiosity lighting.
>
> Thank you, I will try out radiosity.
>
> > Maybe put it right in front of a goldfish bowl... :-)
>
> Nah, I don't think those would fit well together...

A clay goldfish bowel ^_^

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> A clay goldfish bowel ^_^

You were correct in your other reply . . .
 . . . you have been looking at cgg images too long . . . :))
**
Y

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