OK, just showing off my progress here.
Fur can now be added to any object, irrespective of shape/position etc.
But, TINSTAFL. Parse times skyrocket: this one took >15 minutes to
parse. I can probably reduce this, but the memory hit remains. This
scene has 85000 cones (~17000 hairs at 5 cones/hair for smooth
curvature). Unless you have at least 128M RAM - and I don't - it's a
real pain.
You can see that hairs still sprout out in a regular grid; I'll fix this
soon. The "baldness" at the top is partly intentional - hairs get
shorter towards the top. Just for fun.
When all is done (and there's sufficient interest) I'll post the source,
ASAP, for your inspection. Beware, it has a load of parameters and I
ain't gonna reduce them by much. Also, it is restricted to the
Superpatch, as it uses trace()

Oh, and TINSTAFL = There Is No Such Thing As a Free Lunch

Margus

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Attachments:
Download 'shagtxt2.jpg' (112 KB)

Preview of image 'shagtxt2.jpg'

Whoa... needs some brill-creme and a razor and you'll be done.

I've run into the same problem... get around 120,000 objects and if you don't have a
machine with 100meg of memory or better,
you top out about there for any kind of rendering.  I usually hope for enough detail
to say I've finished a particular scene
but as with any render, you always could add a few thousand more itty bitty things.

Great Hair!

Regards,
Robert J Becraft
aka cas### [at] aolcom

Margus Ramst wrote:

> OK, just showing off my progress here.
> Fur can now be added to any object, irrespective of shape/position etc.
> But, TINSTAFL. Parse times skyrocket: this one took >15 minutes to
> parse. I can probably reduce this, but the memory hit remains. This
> scene has 85000 cones (~17000 hairs at 5 cones/hair for smooth
> curvature). Unless you have at least 128M RAM - and I don't - it's a
> real pain.
> You can see that hairs still sprout out in a regular grid; I'll fix this
> soon. The "baldness" at the top is partly intentional - hairs get
> shorter towards the top. Just for fun.
> When all is done (and there's sufficient interest) I'll post the source,
> ASAP, for your inspection. Beware, it has a load of parameters and I
> ain't gonna reduce them by much. Also, it is restricted to the
> Superpatch, as it uses trace()
>
> Oh, and TINSTAFL = There Is No Such Thing As a Free Lunch
>
> Margus
>
>                                                  
------------------------------------------------------------------------
>  [Image]

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Yeah, my sentiments exactly (about the memory/object amount). I have a
Christmas tree written yet unrendered due to my meager 64 megs. Usually
there seems little need for such great numbers of "objects" in the
everyday scene, though this is an oversight since you never know when
you'll ditto objects so prolifically.
The shag is novel, like it a lot. I threw a food item away yesterday
that looked related to it.


Robert J Becraft wrote:
> 
> Whoa... needs some brill-creme and a razor and you'll be done.
> 
> I've run into the same problem... get around 120,000 objects and if you don't have a
machine with 100meg of memory or better,
> you top out about there for any kind of rendering.  I usually hope for enough detail
to say I've finished a particular scene
> but as with any render, you always could add a few thousand more itty bitty things.
> 
> Great Hair!
> 
> Regards,
> Robert J Becraft
> aka cas### [at] aolcom
> 
> Margus Ramst wrote:
> 
> > OK, just showing off my progress here.
> > Fur can now be added to any object, irrespective of shape/position etc.
> > But, TINSTAFL. Parse times skyrocket: this one took >15 minutes to
> > parse. I can probably reduce this, but the memory hit remains. This
> > scene has 85000 cones (~17000 hairs at 5 cones/hair for smooth
> > curvature). Unless you have at least 128M RAM - and I don't - it's a
> > real pain.
> > You can see that hairs still sprout out in a regular grid; I'll fix this
> > soon. The "baldness" at the top is partly intentional - hairs get
> > shorter towards the top. Just for fun.
> > When all is done (and there's sufficient interest) I'll post the source,
> > ASAP, for your inspection. Beware, it has a load of parameters and I
> > ain't gonna reduce them by much. Also, it is restricted to the
> > Superpatch, as it uses trace()
> >
> > Oh, and TINSTAFL = There Is No Such Thing As a Free Lunch
> >
> > Margus
> >
> >                                                  
------------------------------------------------------------------------
> >  [Image]

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/POVring.htm
 mailto:inv### [at] aolcom?PoV

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> Oh, and TINSTAFL = There Is No Such Thing As a Free Lunch

Great picture, but its sposed to be "TANSTAFL" - There ain't no such
thing as a free lunch.  In the original Heinlein at least.

I really do like the hair though.

<sighs at great quotes being brought kicking and scremaing into proper
english>

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What book is that from?  I seem to remember it.  Was that "The Moon is a
Harsh Mistress"?  It seems like something I can see the professor
saying.

Steve


Scott McDonald wrote:
> 
> > Oh, and TINSTAFL = There Is No Such Thing As a Free Lunch
> 
> Great picture, but its sposed to be "TANSTAFL" - There ain't no such
> thing as a free lunch.  In the original Heinlein at least.
> 
> I really do like the hair though.
> 
> <sighs at great quotes being brought kicking and scremaing into proper
> english>

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Stephen Lavedas wrote:
> 
> What book is that from?  I seem to remember it.  Was that "The Moon is a
> Harsh Mistress"?  It seems like something I can see the professor
> saying.

Yup.  Was the motto of the moon colony.  

-- 
+----------------------------------------------------------------------+
|Colin Scott McDonald                                  Metro Link, Inc.|
|                veni, vici, volo in dominum redirre                   |
|sco### [at] metrolinkcom                                  www.metrolink.com|
+----------------------------------------------------------------------+

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Margus Ramst wrote:
> 
> OK, just showing off my progress here.
> Fur can now be added to any object, irrespective of shape/position etc.
> But, TINSTAFL. Parse times skyrocket: this one took >15 minutes to
> parse. I can probably reduce this, but the memory hit remains. This
> scene has 85000 cones (~17000 hairs at 5 cones/hair for smooth
> curvature). Unless you have at least 128M RAM - and I don't - it's a
> real pain.
> You can see that hairs still sprout out in a regular grid; I'll fix this
> soon. The "baldness" at the top is partly intentional - hairs get
> shorter towards the top. Just for fun.
> When all is done (and there's sufficient interest) I'll post the source,
> ASAP, for your inspection. Beware, it has a load of parameters and I
> ain't gonna reduce them by much. Also, it is restricted to the
> Superpatch, as it uses trace()
> 
> Oh, and TINSTAFL = There Is No Such Thing As a Free Lunch
> 
> Margus

I was hammering away at a different approach to the problem last night.
I ripped off some code out of Paul T. Dawsons tree.inc file and adapted
it to sphere/cone generation. It's a recursive while loop that spawns
branches. By constraining the child to one branch and adding control
to the angle of the spawn it offered some good control over the shape
of the hair. One problem that remains, and a big one at that, is the
distributions of the object(s) over a non uniform topography or surface.
You seem to have figured that part out but requires a patch or two
to make that work. 

I achieved a 220,000 object render last night. Instead of the hoped for
individual strands it looked nearly like a solid object. And yes there
was a very large memory hit for this. I have 128 megs installed and it
consumed close to 195 megs. My swap kicked in after about 1.2 minutes
and did not stop until the render was over. Parse time wasn't too bad
at around 8 minutes and the render time for the near solid objects was
much shorter than this. It took longer to release the memory than it
did to do the trace.

 Much more work to be done on this and I may abandon all hope.

  For those who are interested but don't wan't to waste time perfecting
their own proceedures for this there is hope in sight for you.

  Chris Colefax is also working on this issue and he has informed me that
he is very close to having it finished and ready for release to the public.
Most of his final work has been in the optimizing of the code to reduce
the memery requirements and reduce object count. He admits there are limits
and people with older computers may have to wait until they can afford a
faster machine, with enough memory to handle the large number of objects
required. That is if they want to get any kind of realistic covrerage for
the object needing hair growth.

-- 
Ken Tyler

mailto://tylereng@pacbell.net

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Ken wrote in message <36CDA893.21865D9A@pacbell.net>...
/.../
>branches. By constraining the child to one branch and adding control
>to the angle of the spawn it offered some good control over the shape
>of the hair.

    I'm not sure I understand, but this sounds a lot like the method I use.
Hairs are created with a separate macro which creates a segmented "worm" out
of cones. It is very controllable - start/end thickness, start/end segment
length, initial orientation, bend, rigidity, randomness etc... I even added
branching once - obviously I wasn't using the macro for hairs then :)

>One problem that remains, and a big one at that, is the
>distributions of the object(s) over a non uniform topography or surface.
>You seem to have figured that part out but requires a patch or two
>to make that work.
>
    That's my main problem, too. Especially getting an even coverage with
few
hairs. Right now, if I want even coverage, I have to use a very high
sampling rate, which inevitably results in a very large number of hairs. To
reduce this number, I would have to implement some kind of a sorting
function. Anybody willing to make a kd-tree or octree in POV code? Not me.
    As for the parse time, I'll revamp the sampling function. This _should_
reduce parse time dramatically. Also, the example uses several features that
are generally unnecessary. For example, each hair has an individual color
gradient that goes from brown at the bottom to white at the top. Did you
notice? Anybody...?

>  Chris Colefax is also working on this issue and he has informed me that
>he is very close to having it finished and ready for release to the public.


This will also be an include file/macro, yes? If so, does it work in
official POV, too? And how?
I think I'll continue my effort despite this daunting competition. It's just
plain fun.

Margus

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Just when I thought I was getting somewhere with Pov, you guys prove I
still have a long ways to go! :)

GrimDude
vos### [at] arkansasnet

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GrimDude wrote:
> 
>   Just when I thought I was getting somewhere with Pov, you guys prove I
> still have a long ways to go! :)
> 
> GrimDude
> vos### [at] arkansasnet

  Margus is ahead of me and we probably both still have quite a ways to go still.
It's probably only relative to where you started and where you intend be when your
done. I haven't set an end point yet so I it's possible that I'm actually less
experienced,
proportionately, than you. Relatively speaking of course.

-- 
Ken Tyler

mailto://tylereng@pacbell.net

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