I need to map a height field onto the inside of a hollow box, but I can only
think of one
way to do this: generate the image that will be used for the height field,
then cut it into
5 pieces (there's no top on the box) and map each piece separately.  I need
to make
sure the edges meet up smoothly... no areas where the separate maps don't
fit together
right.  It would be a lot easier with UV mapping; is it possible to UV map a
heightfield?
I don't think it is, but I haven't really messed with UV mapping yet.

Any help would be greatly appreciated!

--
- Doug Eichenberg
  http://www.getinfo.net/douge
  dou### [at] nlsnet

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In article <39b294c4$1@news.povray.org>, "Doug Eichenberg" 
<dou### [at] nlsnet> wrote:

> I need to map a height field onto the inside of a hollow box, but I 
> can only think of one way to do this: generate the image that will be 
> used for the height field, then cut it into 5 pieces (there's no top 
> on the box) and map each piece separately.  I need to make sure the 
> edges meet up smoothly... no areas where the separate maps don't fit 
> together right.  It would be a lot easier with UV mapping; is it 
> possible to UV map a heightfield? I don't think it is, but I haven't 
> really messed with UV mapping yet.

First, what do you mean by "map a height field onto the inside of a 
hollow box", and what would UV-mapping have to do with a height field 
other than for texturing? You aren't thinking of a bump map instead of a 
height field, are you? A height field is an object, and can't be 
"mapped".

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

<><

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> First, what do you mean by "map a height field onto the inside of a
> hollow box", and what would UV-mapping have to do with a height field
> other than for texturing? You aren't thinking of a bump map instead of a
> height field, are you? A height field is an object, and can't be
> "mapped".

Sorry, my language wasn't too clear on that one.  I want to texture the
inside of a box (minus one side, call it the top, through which the camera
will be looking) with a water-like surface (ripples, wrinkles, whatever).
The texture (or hieght field, or bump map, or whatever I use) needs to
appear like one unified surface over the surface area of the boxes
sides (as if it were UV mapped)  Does that make any sense?  It's a very
simple idea, I'm just having a hard time describing it.

--
- Doug Eichenberg
  http://www.getinfo.net/douge
  dou### [at] nlsnet

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Doug Eichenberg wrote:
> 
> Sorry, my language wasn't too clear on that one.  I want to texture the
> inside of a box (minus one side, call it the top, through which the camera
> will be looking) with a water-like surface (ripples, wrinkles, whatever).
> The texture (or hieght field, or bump map, or whatever I use) needs to
> appear like one unified surface over the surface area of the boxes
> sides (as if it were UV mapped)  Does that make any sense?  It's a very
> simple idea, I'm just having a hard time describing it.
> 

If i understood you right, you want a box with walls of a certain thickness and
with a rough interior surface that is open on the top.

The easiest way would be probably the difference between a regular box and a box
shape isosurface with some additional roughness (noise3d/pigment function)

Christoph

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

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"Doug Eichenberg" <dou### [at] nlsnet> wrote in message
news:39b2a6bb$1@news.povray.org...
| The texture (or hieght field, or bump map, or whatever I use) needs to
| appear like one unified surface over the surface area of the boxes
| sides (as if it were UV mapped)  Does that make any sense?  It's a very
| simple idea, I'm just having a hard time describing it.

I know what you are talking about but even tiling couldn't mesh height
fields in such a way.
You'd get it close to right but every bit of relief on the surfaces would
simply leave a crease.  And even if that were okay the tiling would make
each side the same, or look-alikes.

Bob

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> I know what you are talking about but even tiling couldn't mesh height
> fields in such a way.
> You'd get it close to right but every bit of relief on the surfaces would
> simply leave a crease.  And even if that were okay the tiling would make
> each side the same, or look-alikes.

Exactly the problem I've run into.  I might try Christoph's idea... I'll
have to
check out isosurfaces (ugh...) which I haven't messed with yet.

Thanks for the feedback!
--
- Doug Eichenberg
  http://www.getinfo.net/douge
  dou### [at] nlsnet

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