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Photon Soup Update

timothy posted more than 10 years ago | from the happy-4th dept.

Programming 116

rkeene517 writes "Two and a half months ago I posted an article asking for spare computer cycles. I was swamped by emails and volunteers. After the first weeks most dropped out. The die-hards kept running the program and we simulated 45.3 billion photons. The pictures are here. Thanks to all that helped out. I will be submitting the images to SIGGRAPH 2005 and a paper. (P.S. Never post your email address on slashdot. I got 900 emails! ouch.)"

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hot girl update! (-1, Troll)

Anonymous Coward | more than 10 years ago | (#9605211)

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$Id: ceren.html,v 7.0 2004/01/01 11:32:04 ceren_rocks Exp $

Re:hot girl update! (-1, Troll)

Anonymous Coward | more than 10 years ago | (#9605375)

While Ceren is hot, Linux users prefer her [bakla.net] . As for Apple users, well I won't say (I don't want to sit in the corner).

Look at the pretty pictures, people (1, Troll)

BlackTriangle (581416) | more than 10 years ago | (#9605219)

They really do look very realistic. Unfortunately, they're just lights in a box.

And, by the way (1)

BlackTriangle (581416) | more than 10 years ago | (#9605235)

I look forward to the many Java haters commenting. Keep up the rationality, you Libertarian kooks!

Never post (5, Funny)

bert.cl (787057) | more than 10 years ago | (#9605220)

The pictures are here. Thanks to all that helped out. I will be submitting the images to SIGGRAPH 2005 and a paper. (P.S. Never post your email address on slashdot. I got 900 emails! ouch.)" Within 2 months: "The paper got a prize and I would like to thank everyone who participated PS: Never post pictures of photo's on slashdot, my webserver is nothing but photons now"

Re:Never post (-1, Troll)

theefer (467185) | more than 10 years ago | (#9605237)

I'd be interested in the process you suggest that transforms matter into photons...

Re:Never post (1)

bert.cl (787057) | more than 10 years ago | (#9605246)

Well, the server might burn with such a high heat that there's nothing left but protons, anywayz, it was a joke, but you got me there :D

Re:Never post (1)

JWSmythe (446288) | more than 10 years ago | (#9605374)


I imagine that it just became a pile of magic smoke.

Neutrinos, too (2, Funny)

mangu (126918) | more than 10 years ago | (#9605271)

I'd be interested in the process you suggest that transforms matter into photons...


I don't think this is possible. AFAIK, one could merge that server with another simlar server composed entirely of anti-matter, but then one would be left with a lot of neutrinos, besides the photons.

Re:Neutrinos, too (1)

theefer (467185) | more than 10 years ago | (#9605350)

but then one would be left with a lot of neutrinos, besides the photons.

Yeah, that was my point.

Re:Never post (3, Funny)

Anonymous Coward | more than 10 years ago | (#9605261)

P.S. Never post your email address on slashdot. I got 900 emails! ouch.

Bah, 900 emails is nothing. I'm still wondering how they got my address.

William H. Gates III
bill.gates@microsoft.com

Re:Never post (1)

// (81289) | more than 10 years ago | (#9606066)

"Never post your email address on slashdot. I got 900 emails! ouch."

Lightweight! I get more SPAM than that EVERY DAY!

Re:Never post (1)

IronicCheese (412484) | more than 10 years ago | (#9606618)

poser. ;) Bill's real email is (no secret)

billg@microsoft.com

Re:Never post (1)

angrykeyboarder (791722) | more than 10 years ago | (#9606918)

I suspect that one is long gone as well. It's been circulating the net for years.

Re:Never post (2)

Sri Lumpa (147664) | more than 10 years ago | (#9605287)


Let's just say that after that story he will find out that he didn't need to _simulate_ the 45.3 billions photons.

Re:Never post (2, Funny)

dolphinling (720774) | more than 10 years ago | (#9605366)

Looks like he still needs the computing cycles. There a client we can run for that?

Crap server (1, Insightful)

Anonymous Coward | more than 10 years ago | (#9605221)

You'd think that having a previous story on slashdot would kind of suggest getting a server that doesn't fall over because of the /. effect...

Anybody got mirrors of the pics?

Auto-Mirror (2, Interesting)

andr0meda (167375) | more than 10 years ago | (#9605384)


How difficult could it be to auto-mirror front page stories on /. itself?

I mean, data-wise, local websites probably take up anything under a 100 Meg, and only go a few pages deep. The rest of it can still link to the outside world, since the probability of people following over 2 pages deep links away from the actual report is small. So the outside server could easily survive, and is not forced to switch servers just because there is ONE spike. /. itself Already takes the hit anyway, so it could easily sustain the traffic.

It seems a bit silly to force websites onto larger bandwidth servers because they get linked to from news sites such as these. It's nice for the advancement of broadband, but it's also wastefull in resources most of the time.

Re:Auto-Mirror (1, Informative)

Colonel Cholling (715787) | more than 10 years ago | (#9605498)

RTFFAQ. [slashdot.org]

Re:Auto-Mirror (0, Troll)

afabbro (33948) | more than 10 years ago | (#9605645)

That's not a real answer. It's laziness on the part of the Slashdot "editors".

could try asking permission, but do you want to wait 6 hours for a cool breaking story while we wait for permission to link someone?

Personally, yes. But why not put it to a poll? In fact, I submitted it as a poll question and...it was rejected.

So the quick answer is: "Sure, caching would be neat." It would make things a lot easier when servers go down, but it's a complicated issue that would need to be thought through in great detail before being implemented.

God forbid the editors would actually do some work! Let's see, they don't read the site (ever see a comment from an editor?), they don't check for dupes, they can't be bothered to spell-check, they don't do new graphics or site design, and the code doesn't change much. What do they do? Make excuses.

Re:Auto-Mirror (3, Interesting)

Ieshan (409693) | more than 10 years ago | (#9605741)

I'm feeding a troll, so I'm posting without bonus to lessen the ugly karma hit.

Don't be ridiculous. Caching DOES have very tricky issues dealing with copyright infringement.

My suggestion for Caching, though:

Enable submitter-optional caching, don't cache sites with any ad banners, only cache a site AFTER a cache.txt file has been placed in the home directory of the site with a listing of the files allowed to be cached (check it once every 5 minutes or so).

Re:Auto-Mirror (1)

JohnGalt00 (214319) | more than 10 years ago | (#9606960)

Enable submitter-optional caching, don't cache sites with any ad banners, only cache a site AFTER a cache.txt file has been placed in the home directory of the site with a listing of the files allowed to be cached


the cache.txt idea sounds great, but the submitter is not always the owner of the site. It sounds like you could just cache based on the presense of the cache.txt file.

Re:Auto-Mirror (1)

AmericanInKiev (453362) | more than 10 years ago | (#9607127)

A Website can be cached and forwarded without copyright issues - much of the web is locally cached at some intersection in any event - and all of it is buffered and forwarded.

however - to properly service the advertisers - a cahing service would serve a frequently refreshed copy - count the copies, and then over time - request page views to correspond to the copies served.

AIK

Re:Auto-Mirror (0)

Anonymous Coward | more than 10 years ago | (#9605744)

"What do they do? Make excuses. "

No sure, shitlock. It's something we've known for quite a while now. You really think bitching is going to get them off their asses? Get real.

Re:Auto-Mirror (1)

asscroft (610290) | more than 10 years ago | (#9605985)

"caching would be neat but it's a complicated issue that needs to be thought through before being implimented"

So think it through already. It's been how many years? When that was written google didn't even exist. Since then google has implimented a wonderful caching system that seems to work. If the geniuses at google can figure out how to cache the entire freaking intarweb, surely people smart enough to bring us slashdot can figure out a way to cache 7 or 8 sites.

Re:Auto-Mirror (0)

Anonymous Coward | more than 10 years ago | (#9606774)

How difficult could it be to search google for the URL and then click its cached page?

I mean, time-wise, googles website probably takes up anything under 1GB a day, and goes several pages deep.

post your address? (0, Redundant)

ender1598 (266355) | more than 10 years ago | (#9605223)

Yeah, never post your server address either. Looks like it's already down with only 1 comment!

Never post your site, either (4, Funny)

marsu_k (701360) | more than 10 years ago | (#9605227)

(P.S. Never post your email address on slashdot. I got 900 emails! ouch.)
One comment and cpjava.net is already inaccessible... guess you shouldn't post links either :-)

never post your url either ;) (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#9605229)

it's dead by now ;) mirrors anyone?

Freecache (0, Redundant)

BReflection (736785) | more than 10 years ago | (#9605230)

Try these:
http://freecache.org/http://www.cpjava.net/photonp roj.html [freecache.org] (site)
http://freecache.org/http://www.cpjava.net/tracer_ 1_3.zip [freecache.org] tracer_1_3.zip (115 KB)
http://freecache.org/http://www.cpjava.net/tracer_ 1_1.tar.Z [freecache.org] tracer_1_3.tar (1.2 MB) (sorry, no compression this time.)

Re:Freecache (0)

Anonymous Coward | more than 10 years ago | (#9605252)

These are also ./'ed

Re:Freecache (1)

1u3hr (530656) | more than 10 years ago | (#9605264)

Try these:

All dead as I type.

Re:Freecache (0)

BReflection (736785) | more than 10 years ago | (#9605280)

Looks like I got to them too late. They were working when I initially posted them, and they still work for me, but i imagine it has to do with it being cached in a server near your area.

I wish people would start using it in their articles. It would help negate the /. effect.

Re:Freecache (0)

Anonymous Coward | more than 10 years ago | (#9606540)

I wish people would start using it correctly. None of those files were cached because none of them were more than 5 MB.

Re:Freecache (1, Funny)

Anonymous Coward | more than 10 years ago | (#9605301)

All dead as I type.

Now's your chance to direct a slashdotting. Try things like

The pictures are available at www.sco.com

Re:Freecache (1)

JWSmythe (446288) | more than 10 years ago | (#9605381)


Make the link go to a particularly slow CGI for full effect. :)

Re:Freecache (3, Informative)

Halo1 (136547) | more than 10 years ago | (#9605308)

Since freecache only caches files >5MB, this isn't going to help anything (freecache is just going to pass those requests through to the original server)...

MOD -1, WRONG (0)

Anonymous Coward | more than 10 years ago | (#9605315)

Freecache won't cache those because they're under 5Mb, and those aren't the interesting files anyway, we want to see the images.

Wow. (0, Offtopic)

James A. S. Joyce (784805) | more than 10 years ago | (#9605234)

Subjecting yourself to two slashdottings in a row - you're taking quite a bullet for science, huh? I'd be more impressed if you people could simulate turbulent fluid flow, huh?

GNAA [www.gnaa.us]

interesting. (0, Redundant)

zushiba (676531) | more than 10 years ago | (#9605241)

If he was /.ed before why would he not set up mirrors in anticipation of this event?

Sorry... (1)

nycsubway (79012) | more than 10 years ago | (#9605244)

I see 45.3 billion photons... but man are they slow! This page is taking forever to load..

Re:Sorry... (0)

Anonymous Coward | more than 10 years ago | (#9605281)

They are not slow, just tired. What would you expect.. the guy drives them crazy for a long time, and just as they get a break 45.3 billions of ./ readers are here screaming out: I want to see it, I want to see those photons.

10 fempto seconds (2, Informative)

goombah99 (560566) | more than 10 years ago | (#9605516)

IIRC, 1 watt-second of light contains about 4xE+19 visible wavelength photons. So if the scene is illumnated with a 100 watt bulb then 4 Billion photons is equivalent to a 10 fempto second shutter speed.

Of course if he was infact only modeling the photons that made it to the lens then the number might be a few hundred times larger.

Thus I dont understand why this page is taking so long to load. If he had just put those photons into the optical fiber carrying my web connection I would have gotten them sooner.

units? (0)

Anonymous Coward | more than 10 years ago | (#9605747)

1 watt-second of light

Otherwise known as 1 joule of light?

Re:units? (0)

Anonymous Coward | more than 10 years ago | (#9606083)

1 joule of light

otherwise known as a watt-second right?

besides chicken/egg logic, the watt-second description is more appropos to purpose of comparion to watts and..er.. seconds.

Re:Sorry... (0)

Anonymous Coward | more than 10 years ago | (#9605598)

It's Schroedinger's computer: Thousands of observers break its delicate state of superposition, and in this case it has dropped into a state of unresponsiveness.

Never post your link on slashdot! (0, Redundant)

Telcontar (819) | more than 10 years ago | (#9605255)

P.S.: Never post your URL on slashdot! I got 900 hits per second! Ouch!

Re:Never post your link on slashdot! (0)

Anonymous Coward | more than 10 years ago | (#9605309)

P.S.: Never post your URL on slashdot! I got 900 hits per second! Ouch!

What link was that?

/ heh

Re:Never post your link on slashdot! (0)

Anonymous Coward | more than 10 years ago | (#9605368)

... so many real emails that there was no room for spam.

I missed this I guess... (0)

liquidpele (663430) | more than 10 years ago | (#9605259)

What was the point?
Was he just trying to make pretty pictures, or was their a point to actually simulating all these photons?

Re:I missed this I guess... (3, Informative)

gl4ss (559668) | more than 10 years ago | (#9605311)

read the fucking blurb?

** I will be submitting the images to SIGGRAPH 2005 and a paper.**

the images make a nice addition to the paper.. to show that the technique actually works.

Re:I missed this I guess... (1)

BarryNorton (778694) | more than 10 years ago | (#9605372)

read the fucking blurb?

I think that's really uncalled for - too little information is included in not just this article, but the original too.



Granted a person needs to protect their work until published, but 'simulating photons' is way too little to give away...


Re:I missed this I guess... (1)

liquidpele (663430) | more than 10 years ago | (#9605373)

Ok, then I guess my question is what is the point of his paper the images are for? Just the technique of being able to simulate photons, or is he trying to proove something else by simulating them?

Re:I missed this I guess... (0)

Anonymous Coward | more than 10 years ago | (#9605538)

well none of us know any more than you can find out by visiting his site. or just wait for the paper, sweetheart.

Re:I missed this I guess... (5, Informative)

TheGavster (774657) | more than 10 years ago | (#9605595)

Photons mapping is currently used on a small scale in some rendering engines to more accurately simulate light bounces. Its particularly useful at calculating caustics (light getting focused through a transparent medium) which can't be done by the less intensive radiosity systems. This experiment, however, seems to try to render using photon mapping exclusively. Nice idea, though not really practical at the present state of computing, given the graininess of the images and the amount of processing time. The Brazil rendering system (http://www.splutterfish.com/sf/sf_gen_page.php3?p rinter=1&page=brazil) for example, uses photon mapping on a much small scale (usually between 1-10M photons) in combination with raytracing to provide clear, realistic imagery (though not as technically perfect as this example)

Re:I missed this I guess... (1)

cjameshuff (624879) | more than 10 years ago | (#9606741)

Another rendering system that supports photon mapping is POV-Ray, the Persistance Of Vision Raytracer. Unlike Brazil, it is free, and although it is not Open Source, the source code is available, and you can distribute patches and, with some restrictions, modified versions.

To summarize,
Forward raytracing: traces actual photons through the scene from the light source, reflecting off/refracting through objects in the scene, and through the camera aperture onto the "film". You end up tracing many photons that will never hit the camera, and the results are blurry or grainy unless you use settings that are just impractical with current technology.

Backwards (traditional) raytracing: traces the light paths backwards, out through the camera onto an object in the scene. From there, rays are traced to the lights in the scene to check for shadowing objects. This works pretty well, but can not compute illumination from mirrored reflections or refraction. However, it can compute diffuse reflection, by tracing more rays to find the illumination of the surrounding scene. This is usually slower than scanline rendering, but produces very good results.

Photon mapping: forward raytracing (like that used in this project) is used to build a map of photons deposited on surfaces within the scene, which is then used in the illumination computations when the scene is rendered with backwards raytracing or scanline rendering.

Re:I missed this I guess... (1)

glyph42 (315631) | more than 10 years ago | (#9606771)

I don't quite get why 45 billion photons is such a big deal. People do iterative photon mapping techniques, where you do 100 million photons each pass, and you do as many passes as you like. If you're using a splatting method this works trivially. 45 billion photons in a good implementation should run in about 1 week on a single P4 machine. I guess I need to read his paper to see what he's doing differently.

You asked the wrong question (0, Redundant)

mangu (126918) | more than 10 years ago | (#9605278)

I posted an article asking for spare computer cycles.


You should have posted an article asking for spare servers.

endangered specIEs on the internet? (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#9605297)

kind of rhymes with feekeys.

the badtoll for yOUR 'independence' being extracted from you buy yOUR owned corepirate nazi felon glowbull warmongering execrable, is absolutely unpayable by any population. lookout bullow.

all is not lost.

consult with/trust in yOUR creators.... doggedly rebuilding civilizations since/until forever. see you there?

Slashdotted (0, Redundant)

Barryke (772876) | more than 10 years ago | (#9605300)

(P.S. Never post your email address on slashdot. I got 900 emails! ouch.)"

Never post your url or you'll get slashdotted !

Re:Slashdotted (0)

Anonymous Coward | more than 10 years ago | (#9607965)

And you'll get 900 posts making jokes about getting slashdotted.

a billion points of light...? (-1, Offtopic)

erroneus (253617) | more than 10 years ago | (#9605319)

Is that what the ex-president was talking about? Has anyone ever figured it out?

Not everyone who mailed him got an answer (1, Troll)

los furtive (232491) | more than 10 years ago | (#9605322)

Never post your email address on slashdot. I got 900 emails!

I remember sending him an email. I also remember mentioning that the methodology (him mailing you the file) as opposed to downloading it or using Java Webstart [sun.com] was not the smarted way to go about doing this.

Finally, I also remember he never sent me an invite even though I asked. Oh well, glad it worked out for him in the long run.

Re:Not everyone who mailed him got an answer (1)

BarryNorton (778694) | more than 10 years ago | (#9605382)

A bittorrent of the program, together with a copy of the original paper, and then of the results, and I might actually have bothered...

Re:Not everyone who mailed him got an answer (2, Informative)

rkeene517 (637993) | more than 10 years ago | (#9607676)

My most sincere appologies. I had so many emails that I couldn't reply to them all. I ended up putting the code on my web site, which is what I should have done in the first place. This is the first time I ever posted to slashdot and it was a learning experience.

never bother (0)

Anonymous Coward | more than 10 years ago | (#9605329)

reading a slashdot article which mentions something about servers i got 900 posts saying "never post your server address on slashdot!" ouch!

/.ed (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#9605331)

/.ed already

Heh, so Java's slow indeed (3, Interesting)

vadim_t (324782) | more than 10 years ago | (#9605543)

Computers got 3000 times faster, but Java managed to compensate for 11 years of evolution.

The previous article says:
Year: 1994
Computers: 100 SparcStation 1
Time: 1 month
Photons: 29 billion, 29 billion/month

Now we have:
Year: 2004
Computers: Unknown, supposedly 3000 times faster
Time: 2.5 months
Photons: 45.3 billions, 18 billion/month

If computers are indeed 3000 times faster, or heck, even 100, you should have got 72 billion just out of one of those computers running for the 2.5 months.

Re:Heh, so Java's slow indeed (1)

kingkade (584184) | more than 10 years ago | (#9605971)

Gee where to start...

Scaling from 1 month to 2.5 doesn't mean 2.5 times the simulated photons, it could be that he didn't even have a fraction of the users he had back in '94. Also scaling raw Hz clock cycles which is where the "3000 times faster" remark expertly refers to is a terrible measure of extrapolating waht the performance should be. It must suck being so stupid.

Re:Heh, so Java's slow indeed (1, Informative)

vadim_t (324782) | more than 10 years ago | (#9606234)

Well, let me explain in more detail.

In 1993, the computer I had was a 386 DX 40 with 4 MB RAM and 170MB hard disk. 486 were recent and still very expensive.

Today, I have a dual Athlon MP 2000+ with 1 GB ECC DDR RAM and 200GB disk which when I bought it, cost me about the price of a high-end single CPU computer and definitely performed better.

After googling a bit, I found a Sparc Station 1 had a 25 MHz CPU, 64MB RAM, and a 25 MHz bus. While I know perfectly that MHz is not a good measure of performance, just the 25 MHz bus would ensure that machine would have a MUCH lower performance than anything modern.

Now, while Sun hardware at that point was probably way beefier than consumer stuff, these days it doesn't seem to be true for Sun hardware that has an affordable price.

So, let's try a little estimation. Assuming current hardware has a performance of only 10X of the Sparc Station 1, he should have got the same result with just 10 volunteers running 24/7. From the 900 emails figure it sounds like he got quite a few more than that.

And despite this increase in computing power, somehow his per-month performance was lower than 11 years ago.

Re:Heh, so Java's slow indeed (2, Insightful)

Anonymous Coward | more than 10 years ago | (#9606504)

I don't think he's computing the same scene as in 1993. It's likely much more complex. Also, more complex algorithms could be used. In other words, you can't really compare (with the data you have).

Re:Heh, so Java's slow indeed (0)

Anonymous Coward | more than 10 years ago | (#9607675)

But the point is that much more complex algorithms weren't used (this is absolutely brute force -- improvements could only make it faster)... only the implementation language and the hardware have changed. The hardware is so much faster that you would have expected wildly better results but since we didn't see that it must mean that either the participation level was lower or the implementation language was slower.

Re:Heh, so Java's slow indeed (1)

RedWizzard (192002) | more than 10 years ago | (#9609359)

But the point is that much more complex algorithms weren't used (this is absolutely brute force -- improvements could only make it faster)... only the implementation language and the hardware have changed.
Not true, the phyiscal modelling of the transparent objects could have been made more accurate at the cost of performance. The number and types of objects in the scene will also effect performance. If the scene and algorithm are not identical you can't draw conclusions about the efficiency of the renderer.

Re:Heh, so Java's slow indeed (2, Informative)

QuantumFTL (197300) | more than 10 years ago | (#9607457)

Computers got 3000 times faster, but Java managed to compensate for 11 years of evolution.

If that's not flamebait, I'm not sure what is... Geez, how can you even say that?

The previous article says: Year: 1994 Computers: 100 SparcStation 1 Time: 1 month Photons: 29 billion, 29 billion/month

Now we have: Year: 2004 Computers: Unknown, supposedly 3000 times faster Time: 2.5 months Photons: 45.3 billions, 18 billion/month

If computers are indeed 3000 times faster, or heck, even 100, you should have got 72 billion just out of one of those computers running for the 2.5 months.


Blockquoth the old article:
Now computers are 3000 times faster and I am doing it again only much better, with a smaller aperature, in stereo, with 3 cameras, and with some errors fixed, and in Java.


I don't know about you, but that sounds like to me he is complicating things quite a bit. It's hard to blame his choice of Java language on the slow execution when he's making the problem considerably harder!

Not to mention the fact that his code may not be as efficient... I can write a slow C program too if I use the wrong data structures or a bad algorithm.

You're comparing apples to oranges here. Photon mapping is insanely complex in terms of the computational requirements, and doing 3 cameras with stereo, etc... Yeah.

Re:Heh, so Java's slow indeed (2, Interesting)

rkeene517 (637993) | more than 10 years ago | (#9607656)

Actualy the network computing started with many people rendering the image and after a month only about 5 or 6 people were following through and still rendering. Unfortunately I didn't put in a counter for cumulative CPU hours.

Re:Heh, so Java's slow indeed (1)

tommeke100 (755660) | more than 10 years ago | (#9608202)

who says the problem scales linear? maybe it's not O(n) but O(n*logn) or something. I don't know enough about the subject anyway, but still...
Just think of Fibonacci numbers, maybe to calculate one more photon you need a factor 10 speed up or something.

Re:Heh, so Java's slow indeed (2, Insightful)

RedWizzard (192002) | more than 10 years ago | (#9609303)

who says the problem scales linear? maybe it's not O(n) but O(n*logn) or something.
It pretty much has to scale linearly to be able to distribute it the way he's doing. Also, when you think about it, he's tracing the paths of photons and photons don't really interact with each other so therefore the complexity of the problem scales linearly with the number of photons.

Mirror (5, Informative)

uss_valiant (760602) | more than 10 years ago | (#9605553)

Such a story is useless without the images. So here's a temporary mirror for the resulting images of the project:

Photon Rendering Project: image mirror [ee.ethz.ch]

The mirror won't be up forever.

Re:Mirror - BitTorrent here! (1)

MarcoPon (689115) | more than 10 years ago | (#9607058)

I set up a Torrent here:
Download [80.18.104.202]

I reencoded the PNGs, losslessy recompressing it.
The file is around 2.5MB (original was 3.5MB circa).

Bye!

bout the pics ... (0)

Anonymous Coward | more than 10 years ago | (#9605576)

i just had a look at the pics and it seems someone
has been smoking in that room >:)

900 emails... (-1, Offtopic)

kiwirob (588600) | more than 10 years ago | (#9605614)

Heck I get at least 900 virus emails everyday sometimes over 2000 a day.

Thanks to the guys over at Clam Anti Virus [clamav.net] and MailScanner [soton.ac.uk] most of these get caught at the mail server.

We have a daily humor mailing list with a few 100,000 subscribers and every time a new virus comes out we get blasted from all the unprotected windows/outlook express users.

To make sure we don't get infected and send out virus to all the users we use FreeBSD [freebsd.org] for our desktop OS and Evolution [ximian.com] as our email client.

Oh and then there is all the spam we get sent, thanks to SpamAssassin [spamassassin.org] for filtering most of this out.

Another copy (2, Informative)

andy314 (775757) | more than 10 years ago | (#9605671)

All 6 images: http://ca.geocities.com/andy314_1/photons.tar.gz

Spare computer cycle-tax credits, clearing house (1)

Cloudface (702721) | more than 10 years ago | (#9605798)

It would be useful if the IRS were to offer some kind of tax write-off for use of one's spare computing cycles. I formerly worked in an office where all the desks had networked computers that did...nothing... (except suck down sleep-cycle juice) for twelve to eighteen hours a day, if not 24 hours a day on weekends. Presuming a workaholic who leaves the keyboard alone for eight hours every night (to run to the pharmacy to refill that Provigil prescription?) and crashes on weekends, that's, uh, urm, 88 hours of downtime. Not counting lunch, bathroom breaks, naps, nooners, etc... I kind of wonder what could be accomplished with all this spare (corporate) computing power. It would be thriftful, although perhaps Orwellian on an individual basis, if one could register a CPU with a central gov't agency which could a.) disburse the unused cycles to scientific and commercial endeavors, then b.) give back a modest tax credit. You know--SETI@irs.gov... Is this a truly horrible idea: allowing the Feds (could also be done on a state level--hint, hint, California) unfettered access to your computer? Can't they already get unfettered access if they are all desirous and (legally speaking) puppy-eyed? Having said that I'm therefore pleased that the best-know distributed computing program is out of Berkeley...

650k PNG files? (3, Informative)

fontkick (788075) | more than 10 years ago | (#9605928)

I would recommend that the submitter take down the zips and images and reoptimize them as smaller size JPGs. A 650k file is just crazy for the actual image - which is only 512 pixels wide and blurry (due to depth of field effects). Just go into Photoshop, hit "Save for web", and you can resize and change the JPG settings to your hearts content. I got one of the files down to 12k and it looks fine. These are not highly detailed images to start with. .PNG may be the format of choice for geeks worldwide, but I've always thought it was worthless.

Re:650k PNG files? (2, Informative)

azuretongue (180140) | more than 10 years ago | (#9608132)

Heck use pngcrush
Best pngcrush method = 124 for soup_one.png (32.88% reduction)

Best pngcrush method = 124 for soup_one_2.png (33.17% reduction)

Best pngcrush method = 16 for soup_two.png (36.67% reduction)

Best pngcrush method = 16 for soup_two_2.png (36.85% reduction)

Best pngcrush method = 16 for soup_three.png (28.52% reduction)

Best pngcrush method = 16 for soup_three_2.png (28.57% reduction)

Pngcrush is free, open, and cross platform enough to run on those Sun SparcSataion1s he seems to be using.

1950's Kodacolor, trolls and new techniques (4, Interesting)

theolein (316044) | more than 10 years ago | (#9606114)

Firstly, I'm kind of irritated that the usual slashdot troll crowd expends so much hatred and ignorance on a truly creative project. The technique might not be using OpenGL, DirectX or ATi or NVidia's newest cards, but that is no reason to trash talk a technique that, in a few years time, might revolutionise CGI work in movies.

And in movie production is where this technique will most probably eventually find use. Movie studios have the budget and the server farm equipment to make good use of a time and resource expensive technique such as this.

And they certainly would want to. The images have almost exactly the same quality as grainy 1950's kodacolor or poor images from my 1970's vintage Kodak instamatic. While adding grain to a movie is no problem, most rendering techniques used today produce surfaces that are simply too clean and glass effects that are too clear, and this immediately gets picked up by the human eye, which is very good at subliminally noticing differences in image quality. Tracing the paths of photons and their interaction through and with materials produces images that mimic reality in an excellent way, IMO.

I'm pretty sure that a large cluster, such as the one using Apple's G5s at Virginia tech, running optimised C or C++ code would be able to produce usable footage for movies. And what's more, I'm pretty sure that sooner or later, there will be tools to make this technique more accessable.

Re:1950's Kodacolor, trolls and new techniques (0)

Anonymous Coward | more than 10 years ago | (#9607742)

I'm kind of irritated that the usual slashdot troll crowd expends so much hatred and ignorance on a truly creative project

Indeed. What you are seeing is people who haven't accomplished anything meaningful in their own lives who get jealous when someone else accomplishes something. My ex-girlfriend was like this; hence the "ex-" designation.

It takes more time... (5, Funny)

fok (449027) | more than 10 years ago | (#9606335)

It takes more time to download the images from a slashdotted site then actually render them!

awwww (1)

XO (250276) | more than 10 years ago | (#9606869)

Damn, 900 emails? I get that in spam, in just two days.

*poor timothy* *pity party* awwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww

Re:awwww (1)

thelenm (213782) | more than 10 years ago | (#9607071)

It was rkeene517 who said that, not timothy.

Re:awwww (1)

XO (250276) | more than 10 years ago | (#9607116)

ok, so i wasn't awake when i posted that :P

*pity party anyway*

BitTorrent download (4, Informative)

JackZ (89183) | more than 10 years ago | (#9607072)

Have a link to a BitTorrent tracker with the images [chattanoogastate.edu] .
You will want 'photon_soup'

Jack

Re:BitTorrent download (1)

JackZ (89183) | more than 10 years ago | (#9607403)

The link above [chattanoogastate.edu] also includes a download called 'photon_soup all images and software' which includes the 3 revisions of his Java code as well as some older images that are no longer available.
I do not know how many photons are in the first results. I believe the second results have 30 billion. The 3rd set of results are the current images.

Jack

...howdy... (1)

ronaldyang (167602) | more than 10 years ago | (#9607327)

cool program. what's the license on the java source?

Really Real Fog (0)

Anonymous Coward | more than 10 years ago | (#9607837)

You might want to simulate cleaning your camera lens too. ;)

Java (0)

Anonymous Coward | more than 10 years ago | (#9608258)

Why was this done in Java? Aren't resource-intensive tasks like this one of the main reasons for C?

Year: 1994 Computers: 100 SparcStation 1 Time: 1 month Photons: 29 billion, 29 billion/month Now we have: Year: 2004 Computers: Unknown, supposedly 3000 times faster Time: 2.5 months Photons: 45.3 billions, 18 billion/month

Saving programmer time is a worthy goal, but if Java slows down the simulation (29 bill./mo. ==> 18 bill./mo.) despite massive hardware advancements, DON'T USE IT!!!!

Impressive results (2, Interesting)

phamNewan (689644) | more than 10 years ago | (#9608344)

After finally finding the pictures I was really impressed. Someone noted that rendered images are easily detected by the human eye, but these look like pictures. Granted parts of it are fuzzy, but that is part of what makes it look so real. The actual glass images look very real.

Great job.

Re:Impressive results (0)

Anonymous Coward | more than 10 years ago | (#9608751)

We'll see how the SIGGRAPH committee likes it. From the description given in the previous slashdot article, it sounds like the images are basically generated by the same technique he presented in 1994. The main difference being he's upped the number of photons and done the computation in a distributed manner. That may be a nice piece of engineering work, but it takes a lot more than that to impress SIGGRAPH reviewers these days.

Actuall, I just did a search for this paper on ACM's digital library [acm.org] website and couldn't find this paper in the list of SIGGRAPH 1994 papers. Maybe I missed it, or maybe this was just a sketch or something. Can anyone find the original paper that was supposedly in SIGGRAPH?

gmail account used? (1)

whatsup_will (779381) | more than 10 years ago | (#9608413)

hope u used one, if not bad luck.
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