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Multi-Sampling Anti-Aliasing Explained
Alan writes: "FiringSquad.com just posted a new article explaining how next-generation multi-sampling anti-aliasing works. They claim that it will bring us one step closer to anti-aliasing without a performance hit, and that the technology is going to be implemented in one of the new chips coming out? (NV20 anyone?). It's pretty technical, so only hard-core techies need apply. The link is over here."
Maybe its a limitation of the extremely pipelined graphics architecture prevalent today, but why not use some kind of thresholding algorithm to determine when a pixel needs to be antialiased?
i.e. for each scan line, check the (color or z)value of the current pixel, and only perform the antialiasing step if the difference between them exceeds some value.
As i understand it, FSAA actually antialiases every single pixel.. Surely this is incredibly inefficient, since antialiasing the already bilinearly-interpolated texture of the interior of a polygon is somewhat pointless.
If this approach is unwieldy, i'd be interested to know why.
I gots ta ding a ding dang my dang a long ling long
...just "forget" to clean your glasses for a couple of days. You wont believe what it does to those jagged lines.
This paid my last vacation, it mi
LSI is currently being used all over the place in Non-destructive testing. The movement of these speckles is very sensitive to the movement of the surface. For example, one can cover an inflated airplane tire with laser light and take an image. Next, add an additional 1-5 PSI to the tire and cover it with laser light and reimage it. Now when you subtract the two images, you will get nice 'moirre'-like fringes. Any small gashes or imperfections will be surrounded by many fringes and will be easy to see.
I can recommend an excellent and very readable book on the subject: Gary Cloud's 'Optical Methods of Engineering Analysis'. His text covers Birefringent materials and laser speckle interferometry in graet detail. It also covers many other areas such as Holagrams and I forgot what else.
Keeping
Consider several areas: Games, CG effects for movies/video, impact on system cost.
In games: At some point, focus on technology detracts from the actual game. If it is assumed that the total cost (that amount that will be spent on development) is fixed, then money spent supporting this type of technology will not be spent on more levels, maps, characters, artwork, etc. The key remains suspension of disbelief.
Movies/video: This is interesting, because newer graphics hardware allows PC rendering to look much closer to dedicated CG effects systems. Yet there is a performance gap. Will we be able to make movies on our PCs? Yes. Does anyone care about the difference in rendering quality? Probably not, unless you're trying to get a studio to release your movie.
System Cost: The GeForce II MX that I put into the last system that I built cost about 60% of the price of the EGA card that I bought in 1988 (maybe 1987). Looks great; less filling (time).
Short answer: not much difference. We've definitely reached the point of dimishing returns in application of graphics technology.
Floating face-down in a river of regret...and thoughts of you...
Bruce
Bruce Perens.
Before you try to educate someone else, start with yourself! The light/dark pattern thats seen with the experiment you describe is nothing more than an interference pattern created when the monochromatic and coherent light reflects off the surface of the object you're looking at and strikes your retina.
For a more complete description, take a look at:
http://www.repairfaq.org/sam/laserioi.htm#ioiscs0
Now, as far as eye resolution goes:
"For an eye with 20/20 vision, the angular resolution is 1 arcminute (1/60th of a degree)"
With this information, we can make a good guess at what a monitors resolution "ought" to be.
Take the sine of 1/60º and multiply this by the aproximate distance from the monitor.
At 3 feet, you get about 0.0105 inches. So you need about 100 pixels per inch. Thats 10,000 per square inch.
A 17" monitor is about 13"x10", so a resolution of 1300x1000 should do the trick at 3 feet.
Also, notice the qualifications I made
A 17" monitor...
This shows that the statement: "The human eye can see aliasing artifacts at resolution up to and even beyond 4000x4000, so obviously 1600x1200 is not sufficient.
is meaningless without knowing the viewing distance.
But even knowing the viewing distance still gets us no where. Notice the ought above in quotes. No matter what the resolution of the monitor, there exists textures that will cause aliasing unless other steps are taken. Outline of a proof:
1) Cast one ray from the virtual eye (POV) through each pixel of the screen onto a surface parallel to the screen, but some distance away in the virtual world.
2) Where the cast rays meet the surface, find the texture element of the surface at this intersection and color it white.
3) Color the rest of the texture elements black.
It should be obvious that the surface viewed at this distance with this texture and without anti-aliasing will appear totally white. It should also be obvious that for any resolution we can create a texture that will cause this effect.