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The Quest For Frames Per Second In Games
VL writes "Ever wondered why it is exactly everyone keeps striving for more frames per second from games? Is it simply for bragging rights, or is there more to it than that? After all, we watch TV at 30fps, and that's plenty." This editorial at ViperLair.com discusses motion blur, the frame-rate difference between movies and videogames, and why "...the human eye is a marvelous, complex and very clever thing indeed, but... needs a little help now and then."
1: 30 frames per second is simply not enough. It's fine for movies and TV, but that is only because TV shows and movies are designed around the limits of the medium. Ever notice how TV shows and movies don't have a lot of quick, jerky movements? Those movements lead to motion sickness on TV and in movies, and they are the exact movements in 3D games. 30fps makes me sick, I can tolerate 60fps.
2: Remember, FPS is the *average* framerate. It may dip well below that mark. My goal is not to have the most FPS but to have a reasonably high resolution with FSAA and AF on, all the detail settings to full, and to never have the game dip below my monitor's refresh rate (75Hz).
I messed up the 'quote' delination by putting open-brackets instead of close brackets. Sorry for the jibberish post.
;-) , your eyes hurt (due to rapid depletion of rods) and your cones take effect very rapidly.
This is the Visual Cortex adding motion blur to perceived imagery so that rather than seeing everything in great detail, we are still able to perceive the effect of motion and direction as we ride by. The imagery is smoothly flowing from one point to the next and there are no jumps or flickering to be seen. If the eye wasn't to add this motion blur, we would get to see all of the details still but the illusion of moving imagery would be lost on us, with the brick wall sort of fading in and out to different points. It's pretty simple to test this.
>>This is idiotically wrong. This entire paragraph is predicated on the false assumption that our eye somehow has a "framerate" itself.
It does. It's about 7000 FPS (+ or - for each individual).
The way bio-psychs tested this is by taking a high-speed controllable projecter that ranged from 30FPS to 20000FPS. Subjects were lead into the totally black room with a mic. Then they were directed to look at the projecter screen by a red dot. Once the pattern started, the projecter took a spread of 3 seconds and at 1 frame put a number on screen. The average FPS for the subjects NOT to notice the number was about 7000FPS.
>>>>(Either that, or the false assumption that our eye is basically a CCD with infinite discrimination, also wrong.) It does not. Our eye is fully analog.
You just cant say that. The ion channels are directly countable and lead to a time based binary system like that of morse code. Not even biologists are sure about that.
>>>>>(Go figure.) You get motion blur because the nerves and the chemical receptors can only react so quickly, and because nerves fire as light accumlates on the receptors. Since the receptors are moving quickly relative to the transmitting object, light rays from a given point are smeared across several cones/rods before the full processing of the image can take place. (Now, I'm simplifying because this isn't the place for a textbook on vision, but at least I know I'm simplifying.)
It's not that the rods/cones (rods are black-white, cones are color) react quickly, it's the chemical breakdown takes a while. Take the simple theater test. Go from sunny outside to a theater room. You pretty much cant see anything. It takes about 15 minutes to FULLY 'charge up' the rods back to full usage. But when you walk out of that sucky movie
Other side effects of bright light is that you cannot see absolute 'white' or 'black'. Similar with dark rooms, you cannot easily see color, as it takes high energy photons to allow you to see it.
>>>>>In fact, there's nothing the visual cortex could do to remove the motion blur coming from our eyes, because the motion blur causes actual information loss! (It can (and does) do some reconstruction, but you can't fill in details that don't exist.)