Photon Soup Update 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.)"
Re:Freecache (Score:4, Informative)
Re:I missed this I guess... (Score:4, Informative)
** 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:Auto-Mirror (Score:2, Informative)
10 fempto seconds (Score:3, Informative)
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.
Mirror (Score:5, Informative)
Photon Rendering Project: image mirror [ee.ethz.ch]
The mirror won't be up forever.
Re:I missed this I guess... (Score:5, Informative)
Another copy (Score:2, Informative)
650k PNG files? (Score:3, Informative)
Re:Heh, so Java's slow indeed (Score:1, Informative)
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.
BitTorrent download (Score:4, Informative)
You will want 'photon_soup'
Jack
Re:Heh, so Java's slow indeed (Score:3, Informative)
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:
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:Not everyone who mailed him got an answer (Score:2, Informative)
Re:650k PNG files? (Score:2, Informative)
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.
Re:1950's Kodacolor, trolls and new techniques (Score:3, Informative)
Tracing photons is already used with the technique of photon mapping which you can look up on the net, there is a load of information available on the topic, as well as example numerous images.
It is a pity that he did not use one of the standard scenes available to test renderers because then it would have been easier to compare the results with already existing renderers.
The thing is, while this method has a very accurate way of simulating a scene it has a very simple scene. If you add effects used by normal photon mapping today such as sub-surface scattering (used to create realistic skin on eg Gollum) or hair/fur renderers the computational time increases to something rediculous. Since modern rendering farms struggling with less accurate simulations today it is doubtful that this particular technique is useful.
If fact I doubt that this technique produces a result which is significantly more accurate than eg photon mapping. (Which is, again, why the lack of a standard scene is regrettable.)
But I do agree with you that there are a lot of less than clued in people here at Slashdot who ridicule ideas they have no grasp on how they work. (And as such make fools out of themselves.) And while that may sound as a thinly veiled attack on you it isn't ment as such. If you have some spare time I recommend that you play around with coding rendering software, it's quite easy to produce a working system. And in my experience it is very rewarding.