#Hair/fur materials
5 messages in this thread
Any clues as to making hair or fur look more life like? I have various hair and
fur maps but the edges always look to smooth. Perhaps some sort of selective
pixel dithering routine?
Also, after spending two days creating an animated cat ( it's stil a little
rough) from sctrach, I can see why 3D clip art is $$…
Bill
William,
>> making hair or fur look more life like? <<
to my knowledge this is a very hard thing to do in 3d. The way I believe it is
done, is to post-process the images in 2d with a "fur" filter which would
detect and fuzz-up the edges. This is probably how the polar bear commercials
were done. I don't know of such a filter on the PC but I'll bet there's such a
thing available on the SGI and/or MAC – they seem to get the coolest filters
first, unfortunately 🙁
Martin, I don't know how far along rapture (by xaos) is but as far as I've seen
it will do a fantastic job of hair type effects.
Dave Mennenoh
David,
it seems like Rapture might be useful for fur/like effects but I haven't had a
chance to try it yet.
Hi William,
Seconding the comments of the other participants, and also:
— I saw a very effective use of opacity mapping by Alan Henry in Phil
Shaddock's "3D Modeling Lab" [Waite Group Press, 1994]. He modeled a closeup of
a honeybee in Imagine/PC, and the body had some fairly convincing hair.
The body was texture-mapped to give the proper appearance for most of the
bee. But the silhouettes, as you point out, were too smooth.
Alan solved this by duplicating the body and scaling it up just a smidgin.
This was given a sparse opacity map… the only visible areas were hairlike
strands. This gave the bee a "hairy" silhouette… clever solution.
— As David points out, the Xaos filters excel at this kind of "brushing
engine" work. While you could do this during post within Painter or
DeBabelizer, I don't think it would work for animations — the particles would
need to refer to the object's 3D coordinates in order to look "right" during
movement. Posting in 2D would make the hairs jump around and twitch with each
frame.
Real pretty for stills, though… have you seen Auguste Raffael's "Hairy
Eye" on the Xaos postcards?
— Which brings up procedural pixel-based displacement. Sorry to say, but I
haven't seen anyone hit this on personal computers yet, at least not for
something as involved as hair.
I'm not sure how Rhythm & Hues did the polar bears — I sure as heck hope
they didn't describe geometry for it! — but suspect that it was some sort of
structured particle system, like that explored in Bill Reeve's 1985 SIGGRAPH
paper describing Pixar's "Adventures of Andre and Wally B."
Sort of a wash, Bill, but perhaps that opacity-mapping technique may, ah,
provide a hair-raising experience…. <g>
Regards,
John Dowdell
Macromedia Tech Support