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Perfect Digital Skin
ILMfan writes "BBC Technology is describing a new graphics algorithm for creating perfect virtual skin. This technique by graphics wizard Henrik Jensen (the guy who invented photon mapping) is already being used in movies (it was used on Gollum in Lord of the Rings, and it will be used in the soon-to-be-released van Helsing movie). And perhaps more exciting is that several game companies are planning on using it for their next generation games. So John Carmack are you listening? Any chance this can be included in DOOM3? Of course there are endless other opportunities for virtual humans with perfect skin :-)"
Henrik Wann Jensen also got a technical Oscar earlier this year. This work is actually quite old. See the original Siggraph 2001 paper here.
Don't Panic
http://www.tomshardware.com/graphic/20040504/ati-x 800-04.html
It's gonna make everything look that much sweeter...
-Christopher Wu
http://www.christopherwu.net/
Oops... links from ATI site MUCH faster:
s s-Demo-v1.0.mov
e -Demo-v1.0.mov
http://www2.ati.com/misc/demos/ATI-X800-DoubleCro
http://www2.ati.com/misc/demos/ATI-X800-Subsurfac
-Christopher Wu
http://www.christopherwu.net/
Actually, depending on how long it takes to crank out a flick, it might be cheaper to pay the engineers. Remember, girls are getting paid anywhere from $200-$3000 PER SCENE, maybe 2-3 scenes per day. Add in pay for the guys, cameraman, location rental, etc. (all of which could be pennies based on the current "gonzo" porno trend), and you are talking upwards of 5-10 grand a day. 4 engineers @ $30/hour * 8 hours = $960 / day. Even if it took them a week you might still be saving money.
Green-voting, republican-registered, socialist-libertarian.
The most ridiculous part to me of lens-flare is that originally, it was to be avoided at all costs since it interfered with the suspension of disbelief (ie. it reminds the viewer that they're viewing something seen by a camera, not them), but somehow it got absorbed into the grammar of cinema as being cool. Videogames, not actually using a lens in the rendering process, were immune to the effect, but labored hard in efforts to reproduce it.
Not A Sig
This is also mentioned in his book, (2001), which I highly recommend to anyone interested in raytracing. It's short and about as easy to understand as photon mapping could possibly be.
He has a lot of stuff on his webpage, too, including videos of computer-generated smoke, light through translucent materials, and a good global illumination demo.
For a simpler explaination of what this is all about, there's a photon mapping entry at wikipedia.
-jim
No he didn't make Gollum. Jensen was the main researcher of this new subsurface scattering technique when he was at Stanford (he is now in San Diego). As was mentioned earlier this was published in a SIGGRAPH 2001 paper, so at least the research might date as far back as early 2001, late 2000. Jensen along with Steve Marschner and Pat Hanrahan got a SciTech Academy Award earlier this year for it (though Marc Levoy was omitted).
The original implementation used raytrcing to achieve the effect, to slow for actual production work. Some people from ILM spotted the paper and decided to implement in a way more friendly to production. Originally it was going to be used for Ep. 2, but the research wasn't completed on time. The first time it was applied was for Dobby in Harry Potter and the Chamber of Secrets. Christophe Hery even presented a Stupid RenderMan Trick using shadow buffers that could be applied to SSS. Around that time Ken McGaugh and Joe Letteri left ILM (tough they were involved with this research at ILM) and joined Weta Digital to work on the Two Towers. Consecuently, Hery, McGaugh and Letteri also received a SciTech Academy award this year for finding a way to implement Jensen's SSS in a production environment.
Subsurface scattering is quite old - I learned about it in my graphics classes, and I've been out of school since 1996... here's a 1993 paper on it.
He points out on his web page "Photon mapping is quite good at simulating subsurface scattering, but it becomes costly for highly scattering materials such as milk and skin. For these materials it is better to use a diffusion approximation. The diffusion approximation is much faster than tracing individual photons, and it is simple enough that a BSSRDF can be formulated."
Here's a BSSRDF from a google search.