madd@bu-cs.BU.EDU (Jim Frost) (03/02/88)
RAY TRACING JELL-O BRAND GELATIN
Copyright 1988 ACM
Reprinted with permission from \fICommunications of the ACM\fR, February 1988.
\fINew technology is presented for imaging a restricted class of
dessert foods.\fR
Paul S. Heckbert
Ray tracing has established itself in recent years as the most general
image-synthesis algorithm [10]. Researchers have investigated
ray-surface intersection calculations for a number of surface
primitives. These have included checkerboards [Whitted 80]; chrome
balls [Whitted 80]; glass balls [Whitted 80]; robot arms [Barr 82];
blue abstract things [Hanrahan 82]; more glass balls [Watterberg 83];
mandrills [Watterberg 83]; more mandrills [Sweeney 83]; green fractal
hills [Kajiya 83]; more glass balls [SEDIC 83]; aquatic blobby things
[Kaw 83]; more chrome balls [Heckbert 83]; pool balls [Portner 84];
more glass balls [Kajiya 86].
Unfortunately, \fInobody\fR has ray traced any food. So far, the most
realistic foods were Blinn's classic orange and strawberry images, but
these were created with a scan-line algorithm [2]. The \fIDessert
Realism Project\fR at Pixar is addressing this problem. This article
presents new technology for ray tracing a restricted class of dessert
foods, in particular Jell-O(1) brand gelatin. We believe this method
may have application to other brands of gelatin and, perhaps, pudding
as well.
This article is divided into three parts: methods for modeling static
Jell-O, simulation of Jell-O motion using impressive mathematics, and
ray-Jell-O intersection calculations.
JELL-O SHAPE
To model static Jell-O, we employ a new synthesis technique wherein
attributes are added one at a time using abstract object-oriented
classes we call \fIingredients\fR. Ingredient attributes are combined
during a preprocessing pass to accumulate the desired set of material
properties (consistency, taste, torsional strength, flame resistance,
refractive index, etc.). We use the RLS orthogonal basis (rasberry,
lime, and strawberry), as shown in the figure below, from which any
type of Jell-O can be synthesized [9].
Ingredients are propagated through a large 3-D lattice using
vectorized pipeline SIMD parallel processing in a systolic array
architecture that we call the \fIJell-O Engine\fR. Furthermore, we
can compute several lattice points simultaneously. Boundary
conditions are imposed along free-form surfaces to control the Jell-O
shape, and the ingredients are mixed using \fIrelaxation\fR and
\fIannealing\fR lattice algorithms until the matrix is chilled and
\fIready-to-eat\fR.
JELL-O DYNAMICS
Previous researchers have observed that, under certain conditions.
Jell-O \fIwiggles\fR [8]. We have been able to simulate these unique
and complex Jell-O dynamics using spatial deformations [1] and other
hairy mathematics. From previous research with rendering systems, we
have learned that a good dose of gratuitous partial differential
equations is needed to meet the paper quota for impressive formulas.
Therefore, we solve the Schrodinger wave equation for the Jell-O field
J:
.nf
_2 2m
V J + -- (E - V)J = 0.
h
.fi
Transforming to a spherical coordinate system [7],
.nf
_ dJ 1 dJ 1 dJ
VJ = E -- + E - -- + E ----- --
x dr y r dO z rsinO dP
2
_2 1 d 2 dJ 1 d dJ 1 d J
V J = -- -- (r --) + ------ -- (sinO --) + ------- ---
2 dr dr 2 dO dO 2 2 2
r r sinO r sin O dP
.fi
[Many of the symbols used don't appear in ASCII -- ed]
Fuller has given a concise and lucid explanation of the deviation form
here:
The "begetted" eightness as the system-limit number of the nuclear
uniqueness of self-regenerative symmetrical growth may well account
for the fundamental octave of unique interpermutative integer
effects identified as plus one, plus two, plus three, plus four,
respectively; and as minus four, minus three, minus two, minus one,
characterizing the integers five, six, seven, and eight,
respectively [3].
In other words, to a first approximation:
.nf
----------------------------------------
| J = 0. |
| The Jell-O(r) Equation |
----------------------------------------
.fi
RAY-JELL-O INTERSECTION CALCULATION
The ray-Jell-O intersection calculations fortunately require the
solution of integral equations and the simulation of Markov chains
[6], so they cannot be computed efficiently. In fact, we have proved
that their solution is linear-time reducible to the traveling-salesman
problem, where \fIn\fR is the number of Jell-O molecules, so we can be
sure that ray tracing Jell-O will be practical only on a supercomputer
[5].
IMPLEMENTATION
A preliminary implementation has been completed on a VAX 11/780
running the UNIX(2) operating system. To create a picture using the
full Jell-O Engine simulation, we estimate that 1 CPU eon of CRAY time
and a lot of hard work would be required. We made several simplifying
approximations, however, since the article is due today. As a first
approximation, we have modeled a gelatin cube governed by the
first-order Jell-O equation with judiciously selected surface
properties; that is, color = (0, 255, 0). The frontispiece for this
article was created with this model.
Work is underway on a complete Jell-O Engine implementation using Lisp
\fIflavors\fR. We will shortly begin computing a 100-by-100 image of
a bowl of lime Jell-O using a roomful of Amigas [4]. The picture
should be ready in time for SIGGRAPH with hours to spare.
CONCLUSIONS
Jell-O goes well with a number of other familiar objects, including
mandrills, glass balls, and teapots. The composition and animation
possibilities are limited only by your imagination (personal
communication by Lance Williams, 1980). The Dessert Foods Division is
generalizing the methods described here to other brands of gelatin.
Future research areas include the development of algorithms for ray
tracing puddings and other dessert foods. Another outstanding problem
is the suspension of fruit in Jell-O, in particular, fresh pineapple
and kiwifruit.
Jell-O is:
* visually appealing
* futuristic
* hydrodynamically captivating
* tasty
* goes well with other objects.
\fIAcknowledgements\fR. Thanks to Paul Haeberli for tipping back a few
with me on this research and to H. B. Siegel for key observations.
The SIGGRAPH technical committee also deserves thanks for recognizing
that \fI"there's always room for Jell-O."\fR.
(1) Jell-O is a registered trademark of General Foods.
(2) UNIX is a registered trademark of AT&T Bell Laboratories.
REFERENCES
1. Barr, a. H. Ray tracing deformed surfaces. SIGGRAPH 86 Proc. 20,
4 (Aug. 1986), 287-296.
2. Blinn, J. F. Computer display of curved surfaces. Ph. D. thesis.
Computer Science Dept., Univ. of Utah, Salt Lake City, 1978.
3. Fuller, R. B. \fISynergetics\fR. MacMillan, New York, 1975, p.
125.
4. Graham, E. Graphic scene simulatons. \fIAmiga World\fR (May-June
1987), 18-95.
5. Haeberli, P., and Heckbert, P. A Jell-O calculus. ACM Trans.
Graph. (special issue on ray tracing moist surfaces). Submitted 1872.
To be published.
6. Kajiya, J. T. The rendering equation. SIGGRAPH 86 Proc. 20, 4
(Aug. 1986), 143-150.
7. Plastock, R. A., and Kalley, G. \fISchaum's Outline of Computer
Graphics\fR. McGraw-Hill, New York, 1986.
8. Sales, S. \fIThe Soupy Sales Show\fR. 1966.
9. Weller, T. \fIScience Made Stupid\fR. Houton Mifflin, Boston
Mass., 1985.
10. Whitted, T. An improved illumination model for shaded display.
Commun. ACM 23, 6 (June 1980), 343-349.
CR Categories and Subject Descriptors: C.1.2 [Processor
Architectures]: Multiple Data Stream Architectures (Multiprocessors)
-- \fIarray and vector processors\fR; I.3.7 [Computer Graphics]:
Three-dimensional Graphics and Realism -- \fIcolor, shading,
shadowing, and texture\fR; J.3 [Computer Applications]: Life and
Medical Sciences -- \fIhealth\fR
General Terms: Algorithms, Design, Theory
Additional Key Words And Phrases: Food, gelatin, Jell-O, lattice
algorithm, ray tracing
Author's Present Address: Paul S. Heckbert, Dessert Foods Division,
Pixar, San Rafael, CA 94913-3719.
Permission to copy without fee all or part of this material is granted
provided that the copies are not made or distributed for direct
commercial advantage, the ACM copyright notice and the title of the
publication and its date appear, and notice is given that copying is
by permission of the Association for Computing Machinery. To copy
otherwise, or to republish, requires a fee and/or specific permission.ph@degas.Berkeley.EDU (Paul Heckbert) (03/02/88)
In article <20312@bu-cs.BU.EDU> madd@.UUCP (Jim Frost) writes: >RAY TRACING JELL-O BRAND GELATIN > >\fINew technology is presented for imaging a restricted class of >dessert foods.\fR >... Please get this garbage off the net! We're carrying on a serious technical discussion here and we don't need this sort of facetious drivel tying up the phone lines and wasting my tax dollars!! What I want to know is: (1) Does anyone have an implementation of GKS for the EGA board in 8008 assembler? (2) I just bought an Apple II and I want to know how to get NTSC video out of it so I can make great films like Luxo Jr. (3) What's the formula to convert RGB to luminance? I've been using sin(R)+atanh(G)*log(B), but I'm getting strange results.
ksbooth@watcgl.waterloo.edu (Kelly Booth) (03/02/88)
In article <20312@bu-cs.BU.EDU> madd@.UUCP (Jim Frost) writes: > >RAY TRACING JELL-O BRAND GELATIN > >Copyright 1988 ACM >Reprinted with permission from \fICommunications of the ACM\fR, February 1988. Actually, this is reprinted by permission from \fIComputer Graphics\fP, Vol. 21, No. 4, July 1987, pp. 73-74. (This is the SIGGRAPH '87 conference proceedings.) The CACM version is itself a reprint. Both are ACM publications.
roy@phri.UUCP (Roy Smith) (03/02/88)
ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: > > \fINew technology is presented for imaging a restricted class of > > dessert foods.\fR > > Please get this garbage off the net! We're carrying on a serious technical > discussion here and we don't need this sort of facetious drivel [...] The more interesting question is do you want to see this sort of drivel in a supposedly well-respected academic journal? If anybody doesn't know what I'm talking about, take a peek at the latest CACM. -- Roy Smith, {allegra,cmcl2,philabs}!phri!roy System Administrator, Public Health Research Institute 455 First Avenue, New York, NY 10016
dave@sun.soe.clarkson.edu (Dave Goldblatt) (03/02/88)
In article <23187@ucbvax.BERKELEY.EDU> ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: >In article <20312@bu-cs.BU.EDU> madd@.UUCP (Jim Frost) writes: >>RAY TRACING JELL-O BRAND GELATIN >> >>\fINew technology is presented for imaging a restricted class of >>dessert foods.\fR >>... > >Please get this garbage off the net! We're carrying on a serious technical >discussion here and we don't need this sort of facetious drivel tying up the >phone lines and wasting my tax dollars!! > Considering you're on the Internet, the lines would be tied up anyway. That's what they are there for. What do your tax dollars have to do with it? I for one found the posting to be quite amusing, and would like to thank Jim for posting it! :-) > >What I want to know is: > Is that a question or a statement? > (1) Does anyone have an implementation of GKS for the EGA board > in 8008 assembler? God, I hope not. I haven't seen an 8008 machine in 10 years. Didn't even know they have EGA support on them! Send all responses to /dev/null. -dg- Internet: dave@sun.soe.clarkson.edu BITNET: dave@CLUTX.Bitnet uucp: {rpics, gould}!clutx!dave Matrix: Dave Goldblatt @ 1:260/360 "All the world's indeed a stage And we are merely players Performers and portrayers Each another's audience Outside the gilded cage" -- "Limelight", Rush
jonathan@pitt.UUCP (Jonathan Eunice) (03/03/88)
Oh, pleeeaaaaasseeeee!!! Didn't this appear in ACM SIGGRAPH Proceedings a number of *years* ago? Like 1983? It was a cute submission, but only once, Jim.
spencer@ogg.cgrg.ohio-state.edu (PROCEED) (03/03/88)
In article <3170@phri.UUCP>, roy@phri.UUCP (Roy Smith) writes: > > The more interesting question is do you want to see this sort of > drivel in a supposedly well-respected academic journal? If anybody doesn't > know what I'm talking about, take a peek at the latest CACM. > -- It first appeared in the 1987 ACM SIGGRAPH proceedings. Good for a chuckle or two, but, like you said, not really what is expected of an academic journal. How about "The Journal of Irreproducible Results"?? -- "I feel like I'm stranded on a sandbar..." Stephen Spencer, Graduate Student | The Computer Graphics Research Group | {cbosgd,ucbvax}!osu-cis!ogg!spencer The Ohio State University | spencer@ogg.cgrg.ohio-state.edu 1501 Neil Avenue, Columbus OH 43210 |
b-davis%cai.utah.edu@utah-cs.UUCP (Brad Davis) (03/03/88)
In article <1109@ogg.cgrg.ohio-state.edu> spencer@ogg.cgrg.ohio-state.edu (PROCEED) writes: >In article <3170@phri.UUCP>, roy@phri.UUCP (Roy Smith) writes: >> >> The more interesting question is do you want to see this sort of >> drivel in a supposedly well-respected academic journal? If anybody doesn't >> know what I'm talking about, take a peek at the latest CACM. >> -- > >It first appeared in the 1987 ACM SIGGRAPH proceedings. Good for a chuckle >or two, but, like you said, not really what is expected of an academic >journal. How about "The Journal of Irreproducible Results"?? Oh, come on. The ACM seems to be the only professional organization (academic or otherwise) that can laugh at itself and its industry. Now if the IEEE could do something with its elections :-) P.S. Displaying realistic foods is difficult. Brad Davis {ihnp4, decvax, seismo}!cs.utah.edu!cai.utah.edu!b-davis b-davis@cs.utah.edu, b-davis@cai.utah.edu One drunk driver can ruin your whole day.
kosugi@ttrdf.UUCP (Irving C. Moy) (03/03/88)
In article <3170@phri.UUCP>, roy@phri.UUCP (Roy Smith) writes: > ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: > > > \fINew technology is presented for imaging a restricted class of > > > dessert foods.\fR > > > > Please get this garbage off the net! We're carrying on a serious technical > > discussion here and we don't need this sort of facetious drivel [...] > > The more interesting question is do you want to see this sort of > drivel in a supposedly well-respected academic journal? If anybody doesn't > know what I'm talking about, take a peek at the latest CACM. > -- > Roy Smith, {allegra,cmcl2,philabs}!phri!roy > System Administrator, Public Health Research Institute > 455 First Avenue, New York, NY 10016 This paper was presented at SIGGRAPH '87 in Anaheim, CA and the audience (including myself) thought it was rather amusing. Maybe it's funnier after you've been sitting in a dark arena for what seems to be eons, listening to *serious* papers being presented. Kinda' breaks up the routine, ya' know. :-):-):-) I admit that its publication in CACM may have been a mistake since the humor is not readily apparent in that context. Maybe the editors were trying to "lighten-up" the tone of CACM. Oh well, at least they tried. Irv Moy mail address: UNKNOWN since I am changing employers Disclaimer: If I knew what I was doing, I'd be dangerous. Besides, do you really think AT&T would let ME represent them???
eugene@eos.UUCP (Eugene Miya) (03/04/88)
In article <3444@watcgl.waterloo.edu> ksbooth@watcgl.waterloo.edu (Kelly Booth) writes: >In article <20312@bu-cs.BU.EDU> madd@.UUCP (Jim Frost) writes: >>RAY TRACING JELL-O BRAND GELATIN >>Copyright 1988 ACM > >Actually, this is reprinted by permission from \fIComputer Graphics\fP, >Vol. 21, No. 4, July 1987, pp. 73-74. (This is the SIGGRAPH '87 >conference proceedings.) The CACM version is itself a reprint. Both >are ACM publications. Yes, but Kelly, as the CACM reprint points out, it does include several significant pictures and images not printed with the Conference Proceedings (I'm standing up for Greg Ward since he doesn't have a Usenet machine ;-). Don't worry, we will coerce Paul to give the talk again in the Bay Area. From the Rock of Ages Home for Retired Hackers: --eugene miya, NASA Ames Research Center, eugene@ames-aurora.ARPA "You trust the `reply' command with all those different mailers out there?" "Send mail, avoid follow-ups. If enough, I'll summarize." {uunet,hplabs,hao,ihnp4,decwrl,allegra,tektronix}!ames!aurora!eugene
ksbooth@watcgl.waterloo.edu (Kelly Booth) (03/04/88)
>It first appeared in the 1987 ACM SIGGRAPH proceedings. Good for a chuckle >or two, but, like you said, not really what is expected of an academic >journal. How about "The Journal of Irreproducible Results"?? 1. Hopefully, just as there is always room for Jell-O, there is always (a little) room for humor. The SIGGRAPH '87 program committee did agonize a lot (I am told) over the prudence of including this paper in the conference. I am glad they decided yes. I doubt this will be a regular occurrence at the conference, but every once in a while seems a nice idea. 2. The particular issue of CACM in which this was reprinted had three articles on computer graphics, one a survey article written by ACM staff, one a transcript of Don Greenberg's Coons Award address, and one the Jell-O paper. I actually believe the three taken togehter give a very balanced view of computer graphics. Some will disagree. The article by Greenberg appeared as the result of a request from the SIGGRAPH Executive Committee followed by the usual reviewing procedures for CACM. The article was also printed in the SIGGRAPH newsletter because some members of SIGGRAPH are not members of ACM. Many members of ACM are not members of SIGGRAPH. For this reason we thought it important that the Greenberg article appear in CACM as well. 3. CACM does not profess to be an academic journal in the sense of JACM or similar publications. 4. People do realize that the first complaint on the original posting was made by Paul Heckbert, the author of the article in question? Kelly Booth ACM SIGGRAPH Chair
peterh@tekirl.TEK.COM (Peter Hildebrandt) (03/04/88)
In article <23187@ucbvax.BERKELEY.EDU> ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: >In article <20312@bu-cs.BU.EDU> madd@.UUCP (Jim Frost) writes: >>RAY TRACING JELL-O BRAND GELATIN >> >>\fINew technology is presented for imaging a restricted class of >>dessert foods.\fR >>... > >Please get this garbage off the net! We're carrying on a serious technical >discussion here and we don't need this sort of facetious drivel tying up the >phone lines and wasting my tax dollars!! > I disagree with your pompus attitude. I enjoyed reading this article as much as I enjoyed the presentation of the same paper at Siggraph '87 during the course on ray-tracing. We computer graphics people often spend our day pouring over one boring paper after another, and occasionally need some relief from the tedium. Comic relief should be as much a part of your day as eating lunch. I'm delighted that our company spends money to keep the research from going to our heads. So lighten up, friend. Peter Hildebrandt Tek Labs ...tektronix!tekirl!peterh peterh@tekirl.TEK.COM p
michael@orcisi.UUCP (Michael Herman) (03/04/88)
> drivel in a supposedly well-respected academic journal? If anybody doesn't > know what I'm talking about, take a peek at the latest CACM. Didn't CACM cease being a "well-repected academic journal" about five years ago when it decided that it needed to appeal to a wider audience? Michael Herman Optical Recording Corporation 141 John Street, Toronto, Ontario, Canada M5V 2E4 UCP: {mnetor,yetti,utgpu}!geac!orcisi!michael ALSO: michael@orcisi.uucp
skinner@saturn.ucsc.edu (Robert Skinner) (03/05/88)
In article <1184@tekirl.TEK.COM>, peterh@tekirl.TEK.COM (Peter Hildebrandt) writes: > In article <23187@ucbvax.BERKELEY.EDU> ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: > >>\fINew technology is presented for imaging a restricted class of > >>dessert foods.\fR > >>... > > > >Please get this garbage off the net! We're carrying on a serious technical > >discussion here and we don't need this sort of facetious drivel tying up the > >phone lines and wasting my tax dollars!! > > > > I disagree with your pompus attitude. > > So lighten up, friend. > Lighten up yourself. (You were at Siggraph, you should know.) If you look closely you will see that Paul Heckbert WROTE the ray-tracing Jello article and PRESENTED it at Siggraph. If you had read all of his article, you could see that it was obviously tongue-in-cheek. (intensity = sin(R)+atanh(G)*log(B) !?!?!?, come on) I guess that Paul presumed he didn't need the smiley faces, because people would be more alert. While I'm talking about it, I thought that the Jello article was well done, and the presentation well done and humorous. I wonder though, if it displaced anyone who would have presented a serious and valueable paper. A paper that someone worked hard on to finish by the Siggraph deadline. I also wonder if the same paper/presentation would have been accepted if the author had not been well known and had not worked for Pixar. I enjoyed all the Jello stuff. I just think that there was a more appropriate place for it at Siggraph. Its almost sure to start a trend, what will be the selection criteria for humorous articles? --------------------- Robert Skinner skinner@saturn.ucsc.edu
Edwin_V_Post@cup.portal.com (03/05/88)
Paul Heckbert -- for a while, I thought that "Ray Tracing Jell-O Brand
Gelatin" was the funniest thing that's hit computer graphics since
"The Fun of Interactive Computer Graphics" by Foliage and Pan-Am a few
years back. I was wrong. The funniest thing is your "get this drivel
off the net" article -- pure artistry. I especially like the outraged
responses which defend you against yourself. Keep up the good work.
By the way, I'm the only person in the world who knows the real point-in-
polygon algorithm, and I'm not telling.
-Ed Postpeterh@tekirl.TEK.COM (Peter Hildebrandt) (03/05/88)
In article <1184@tekirl.TEK.COM> peterh@tekirl.UUCP (Peter Hildebrandt) writes: > >I disagree with your pompus attitude. I enjoyed reading this article as >much as I enjoyed the presentation of the same paper at Siggraph '87 during >the course on ray-tracing. > >We computer graphics people often spend our day pouring over one boring >paper after another, and occasionally need some relief from the tedium. >Comic relief should be as much a part of your day as eating lunch. I'm >delighted that our company spends money to keep the research from going >to our heads. So lighten up, friend. A number of people have sent me mail, and boy did *I* get taken in! I knew I recognized the name Paul Heckbert from somewhere, but for some reason I didn't make the connection that *he* had written the Jell-o article. Blush. ---- Peter Hildebrandt Tek Labs ...tektronix!tekirl!peterh peterh@tekirl.TEK.COM
abs@nbc1.UUCP (Andrew Siegel) (03/06/88)
In article <3170@phri.UUCP< roy@phri.UUCP (Roy Smith) writes: <ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: << < \fINew technology is presented for imaging a restricted class of << < dessert foods.\fR << << Please get this garbage off the net! We're carrying on a serious technical << discussion here and we don't need this sort of facetious drivel [...] < < The more interesting question is do you want to see this sort of <drivel in a supposedly well-respected academic journal? If anybody doesn't <know what I'm talking about, take a peek at the latest CACM. C'mon, lighten up, folks! Doesn't *anyone* have a sense of humor on this newsgroup? I thought it was inspired, high-quality humor, with a gaggle of good puns thrown in. -- Andrew Siegel, N2CN NBC Computer Imaging, New York, NY {philabs,steinmetz,ge-dab}!nbc1!abs (212)664-5776
saponara@batcomputer.tn.cornell.edu (John Saponara) (03/07/88)
In article <2201@saturn.ucsc.edu> you write: >While I'm talking about it, I thought that the Jello article was well done, and >the presentation well done and humorous. I wonder though, if it >displaced anyone who would have presented a serious and valueable >paper. A paper that someone worked hard on to finish by the Siggraph >deadline. No, it didn't. As I recall, the Jello paper presentation was about 5 minutes long, and did not displace any papers. It was presented at the end of the Ray Tracing session with time at the break. If you look at the schedule, there were the same number of papers on the first day of the SIGGRAPH '87 Technical Session (when Paul presented his paper) as the year before. Eric Haines (not John Saponara)
saponara@batcomputer.tn.cornell.edu (John Saponara) (03/07/88)
In article <3955@batcomputer.tn.cornell.edu> saponara@tcgould.tn.cornell.edu (John Saponara) writes: >No, it didn't. As I recall, the Jello paper presentation was about 5 minutes >long, and did not displace any papers. It was presented at the end of the Ray >Tracing session with time at the break. If you look at the schedule, there >were the same number of papers on the first day of the SIGGRAPH '87 Technical >Session (when Paul presented his paper) as the year before. > Actually, what Eric meant to say was that there were an equal number of full length papers in addition to Paul's at SIGGRAPH '87 as at SIGGRAPH '86. John Saponara (not Eric Haines)
richard@gryphon.CTS.COM (Richard Sexton) (03/09/88)
In article <1184@tekirl.TEK.COM> peterh@tekirl.UUCP (Peter Hildebrandt) writes: >In article <23187@ucbvax.BERKELEY.EDU> ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: >>In article <20312@bu-cs.BU.EDU> madd@.UUCP (Jim Frost) writes: >>>RAY TRACING JELL-O BRAND GELATIN >>> >>>\fINew technology is presented for imaging a restricted class of >>>dessert foods.\fR >>>... >> >>Please get this garbage off the net! We're carrying on a serious technical >>discussion here and we don't need this sort of facetious drivel tying up the >>phone lines and wasting my tax dollars!! >> > >I disagree with your pompus attitude. I enjoyed reading this article as I agree with Paul. More pompousity. >much as I enjoyed the presentation of the same paper at Siggraph '87 during >the course on ray-tracing. I see. And who presented the paper you heard, Peter ? (And peter...the guy who took your ticket was Robin Wiliams) -- "...(alright Nils, alright)..." richard@gryphon.CTS.COM {ihnp4!scgvaxd!cadovax, rutgers!marque, codas!ddsw1} gryphon!richard
king@dciem.UUCP (Stephen King) (03/09/88)
In article <23187@ucbvax.BERKELEY.EDU> ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: >In article <20312@bu-cs.BU.EDU> madd@.UUCP (Jim Frost) writes: >>RAY TRACING JELL-O BRAND GELATIN >>... > >Please get this garbage off the net! We're carrying on a serious technical >discussion here and we don't need this sort of facetious drivel tying up the *****FLAME ON*** Go soak your head. I got a real laugh out of the referenced posting and I resent you making yourself out to be some net-god with comments like those above. Rendering substances such as Jello creates problems which have real- world significance. A light hearted, even outlandish, approach can stimulate thought and sometimes leads to novel solutions. *****FLAME OFF*** > (1) Does anyone have an implementation of GKS for the EGA board > in 8008 assembler? ^^^^ 8088 assumed. Why spend so much effort on a machine with such miserable graphics performance? Get a REAL graphics engine instead. > (2) I just bought an Apple II and I want to know how to > get NTSC video out of it so I can make great films like Luxo Jr. You will never get Luxo Jr. quality with this approach. NTSC resolution is too low (you need AT LEAST 1k x 1k resolution, preferrable 2k x 2k or even 4k x 4k, available from Dicomed film recorders etc.) Furthermore, the Apple would probably take a great deal of time to render a single frame. For the sake of argument, let's say 24 hours per frame (it may be 2x or 3x this). At motion picture frame rate (24fps), that's 24 days to render one second of playback time. Thus, a fifteen second short would require almost a year of constant computing to produce. Hardly worth the effort. > (3) What's the formula to convert RGB to luminance? E'y = 0.30E'r + 0.59E'g + 0.11E'b E' denote gamma-corrected signals y represents luminance r - red, g - green, b - blue > I've been using sin(R)+atanh(G)*log(B), but I'm getting strange results. No wonder. -- * Defence & Civil Institute * {decvax|ihnp4|watmath}!utzoo!dciem!king * of Environmental Medicine * or uwbeaver!utcsri!dciem!king - Simulation & Training Group - or uunet!mnetor!dciem!king (may or may not endorse my opinions) or dciem!king@zorac.arpa
cc4b+@andrew.cmu.edu (Christopher Brian Cox) (03/10/88)
>. . . >> (1) Does anyone have an implementation of GKS for the EGA board >> in 8008 assembler? > >God, I hope not. I haven't seen an 8008 machine in 10 years. Didn't even >know they have EGA support on them! > . . . Things must be pretty bad when you get serous replies to joke questions. Please, re-read that response to the article. Note the author (of the response). Look familiar? I too found the post amusing, and already thanked Paul Heckbert for writing it. -Chris Cox
ph@degas.Berkeley.EDU (Paul Heckbert) (03/10/88)
In <2201@saturn.ucsc.edu> skinner@saturn.ucsc.edu (Robert Skinner) writes: > I guess that Paul presumed he didn't need the smiley faces, because > people would be more alert. Yes, we're all intelligent readers here, right? (yuk yuk). I don't understand why some USENET folks are so fond of their :-)'s and those silly *stars*, anyway. I find these "netiquette" affectations simply repulsive. The English language is perfectly adequate as is. If I had used the oral equivalent of :-)'s during my presentation of the Jell-O paper at SIGGRAPH it would have spoiled a lot of the fun. For example, a Japanese guy came up to me at a reception the evening after the talk and said "I enjoyed your talk today, but I didn't follow your derivation of the Jell-O Equation". I had to explain that the whole thing was a joke. Seriously! > ... I wonder though, if it displaced anyone who would have presented > a serious and valueable paper. No, I did not want to displace a serious paper. The SIGGRAPH technical committee waited until all of the other papers were selected before deciding on mine. They accepted it only after long debate, apparently, on the strict conditions that I hold the printed version to 2 pages and the presentation to 10-15 minutes (both of which I adhered to). The best surprise was the limited-edition Jell-O t-shirt that Turner Whitted presented to me after the talk. On the back it said (what else?): "There's always room for Jell-O". I've heard that one joke paper was submitted to SIGGRAPH this year, but I don't know what its chances of acceptance are. Paul Heckbert ph@degas.berkeley.edu PS: If you enjoy allegorical parodies like the Jell-O paper, be sure to check out the books by Tom Weller: "SCIENCE MADE STUPID" and "CVLTVRE MADE STUPID". I used the former for style reference while writing Jell-O. PPS: As Tom Weller would say: OBJECTS IN MIRROR ARE CLOSER THAN THEY APPEAR.
skinner@saturn.ucsc.edu (Robert Skinner) (03/11/88)
In article <2690@dciem.UUCP>, king@dciem.UUCP (Stephen King) writes: > In article <23187@ucbvax.BERKELEY.EDU> ph@degas.Berkeley.EDU.UUCP (Paul Heckbert) writes: > > > >Please get this garbage off the net! We're carrying on a serious technical > >discussion here and we don't need this sort of facetious drivel tying up the > > *****FLAME ON*** > Go soak your head. > You will never get Luxo Jr. quality with this approach. ... > (you need AT LEAST 1k x 1k resolution, preferrable 2k x 2k or even > 4k x 4k, For your information: If you check the '87 Siggraph proceedings, page 100, Cook, Carpenter, and Catmull say: "Luxo frames rendered at 724x434 ..." FLAME ON: Does anyone really read the articles in this group? Are these (expletives deleted) articles being posted by robots, or prototype neural net programs? For the most part, the last poster was "talking out the side of his neck". Sorry... I just had to say it. I couldn't help myself. FLAME SUBSIDING... Robert Skinner skinner@saturn.ucsc.edu
elf@dgp.toronto.edu (Eugene Fiume) (03/13/88)
In article <1246@orcisi.UUCP> michael@orcisi.UUCP (Michael Herman) writes: >Didn't CACM cease being a "well-repected academic journal" about five >years ago when it decided that it needed to appeal to a wider audience? > See Peter Denning's article in this issue of CACM (or was it the one before?) on this issue. -- Eugene Fiume Dynamic Graphics Project University of Toronto elf@dgp.utoronto (BITNET); elf@dgp.toronto.edu (CSNET/UUCP)
roy@phri.UUCP (Roy Smith) (03/13/88)
In article <1246@orcisi.UUCP> michael@orcisi.UUCP (Michael Herman) writes: | > drivel in a supposedly well-respected academic journal? | | Didn't CACM cease being a "well-repected academic journal" about five | years ago when it decided that it needed to appeal to a wider audience? Hence the "supposedly". Personally, I find a strong temporal correlation between the decline in the academic value of CACM and the appearance of 4-color covers. -- Roy Smith, {allegra,cmcl2,philabs}!phri!roy System Administrator, Public Health Research Institute 455 First Avenue, New York, NY 10016
roy@phri.UUCP (Roy Smith) (03/15/88)
Yesterday I tried making Jello with oranges and kiwis in it. It
didn't gell. I know oranges are OK because I'm put oranges in Jello
before. I also know you can't put pineapple in Jello because pineapple has
collagenase which keeps the Jello from gelling. Does anybody know if kiwi
fruit also has collagenase?
For you sci.bio people wonderingabout the Subject:, take a peek at
comp.graphics for the past couple of weeks.
--
Roy Smith, {allegra,cmcl2,philabs}!phri!roy
System Administrator, Public Health Research Institute
455 First Avenue, New York, NY 10016andrea@hp-sdd.HP.COM (Andrea K. Frankel) (03/16/88)
In article <3177@phri.UUCP> roy@phri.UUCP (Roy Smith) writes: > Yesterday I tried making Jello with oranges and kiwis in it. It >didn't gell. Does anybody know if kiwi fruit also has collagenase? Some sort of protease, yes - I don't know if it's collagenase. Andrea Frankel, Hewlett-Packard (San Diego Division) (619) 592-4664 "...like a song that's born to soar the sky" ______________________________________________________________________________ UUCP : {ihnp4|decwrl|sun|tektronix|<other hub>}!hplabs!hp-sdd!andrea or {nosc|hpfcla|ucsd}!hp-sdd!andrea Internet : andrea%hp-sdd@ {nosc.mil | sdcsvax.ucsd.edu | hplabs.HP.com} CSNET : andrea%hp-sdd@hplabs.csnet USnail : 16399 W. Bernardo Drive, San Diego CA 92127-1899 USA
dave@onfcanim.UUCP (Dave Martindale) (03/23/88)
In article <2311@saturn.ucsc.edu> skinner@saturn.ucsc.edu (Robert Skinner) writes: >> You will never get Luxo Jr. quality with this approach. ... >> (you need AT LEAST 1k x 1k resolution, preferrable 2k x 2k or even >> 4k x 4k, > >For your information: If you check the '87 Siggraph proceedings, >page 100, Cook, Carpenter, and Catmull say: > "Luxo frames rendered at 724x434 ..." Well, that's part of the story. They were rendered at relatively low resolution with Really Good antialiasing, and then interpolated up to about 3000 pixels across for recording on film using the ILM/Lucasfilm laser film recorder. I assume that the interpolation was done with bicubic interpolation, which apparently runs pretty fast if you have Pixars lying around to do it on. I would be very interested if someone could do a film transfer at 724x434 and get results that looked like Luxo... Dave Martindale