dipityPix app

Thursday, November 23, 2006

Moore's Law and Ray Budget

Moore's Law states the number of transistors on a chip will rise exponentially, and this has happened fairly steadily. A variation relates to performance, which for CPUs has doubled every two years or so. Another variation is that CPU performance per dollar has doubled every 18 months or so. In practice, the cost law implies you can buy more and better CPUs as time goes on. Finally, screen resolution has been on its own curve that doubles the number of pixels every 10 years or so.

What does this mean for rendering? About 27 years ago Turner Whitted ray traced a 640x480 image at about 1 ray per pixel. For the same money budget we can get about 18 doubling of performance, but we have 3 doublings or so in the number of pixels. So now we should be able to do 2.5 million pixels, each with 2^15 = 32k rays.

A caveat is that we want to use more objects. Fortunately, performance in practice is related to the log of the number of objects.

What does this all mean? The rendering community should raise its intuition for how many rays per pixel we can use in practice. In academics, where it is good to think 5-10 years out, we should be looking at another 6 doublings or so, and a million rays per pixel should then be reasonable.

Another way to compute ray budget is to assume 30Hz interactive ray tracing will become practical at 1 ray per pixel. For an 8 hour batch run using the same infrastructure, you can send 30*60*60*8 = 864k samples per pixel.

Bottom line: batch rendering algorithms should assume a million samples per pixel or so are available, and this should make new algorithmic possibilities practical.

1 comment:

sexy said...

情趣用品,情趣用品,情趣用品,情趣用品,情趣用品,情趣用品,情趣用品,情趣用品,情趣,情趣,情趣,情趣,情趣,情趣,情趣,情趣,A片,視訊聊天室,聊天室,視訊,視訊聊天室,080苗栗人聊天室,上班族聊天室,成人聊天室,中部人聊天室,一夜情聊天室,情色聊天室,視訊交友網a片,a片


免費A片,AV女優,美女視訊,情色交友,免費AV,色情網站,辣妹視訊,美女交友,色情影片,成人影片,成人網站,A片,H漫,18成人,成人圖片,成人漫畫,情色網,日本A片,免費A片下載,性愛

A片,色情,成人,做愛,情色文學,A片下載,色情遊戲,色情影片,色情聊天室,情色電影,免費視訊,免費視訊聊天,免費視訊聊天室,一葉情貼圖片區,情色,情色視訊,免費成人影片,視訊交友,視訊聊天,視訊聊天室,言情小說,愛情小說,AIO,AV片,A漫,avdvd,聊天室,自拍,情色論壇,視訊美女,AV成人網,色情A片,SEX,成人論壇

情趣用品,A片,免費A片,AV女優,美女視訊,情色交友,色情網站,免費AV,辣妹視訊,美女交友,色情影片,成人網站,H漫,18成人,成人圖片,成人漫畫,成人影片,情色網


情趣用品,A片,免費A片,日本A片,A片下載,線上A片,成人電影,嘟嘟成人網,成人,成人貼圖,成人交友,成人圖片,18成人,成人小說,成人圖片區,微風成人區,成人文章,成人影城,情色,情色貼圖,色情聊天室,情色視訊,情色文學,色情小說,情色小說,臺灣情色網,色情,情色電影,色情遊戲,嘟嘟情人色網,麗的色遊戲,情色論壇,色情網站,一葉情貼圖片區,做愛,性愛,美女視訊,辣妹視訊,視訊聊天室,視訊交友網,免費視訊聊天,美女交友,做愛影片

av,情趣用品,a片,成人電影,微風成人,嘟嘟成人網,成人,成人貼圖,成人交友,成人圖片,18成人,成人小說,成人圖片區,成人文章,成人影城,愛情公寓,情色,情色貼圖,色情聊天室,情色視訊,情色文學,色情小說,情色小說,色情,寄情築園小遊戲,情色電影,aio,av女優,AV,免費A片,日本a片,美女視訊,辣妹視訊,聊天室,美女交友,成人光碟

情趣用品.A片,情色,情色貼圖,色情聊天室,情色視訊,情色文學,色情小說,情色小說,色情,寄情築園小遊戲,情色電影,色情遊戲,色情網站,聊天室,ut聊天室,豆豆聊天室,美女視訊,辣妹視訊,視訊聊天室,視訊交友網,免費視訊聊天,免費A片,日本a片,a片下載,線上a片,av女優,av,成人電影,成人,成人貼圖,成人交友,成人圖片,18成人,成人小說,成人圖片區,成人文章,成人影城,成人網站,自拍,尋夢園聊天室