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Debunking The Need For 200FPS
Digital_Fusion writes: "If you follow the gaming sites at all you will hear about people that have tweaked their gaming rigs to give 200fps in games like Quake3. Do we really need this kind of framerate? Well no, according to this paper. It seems that anything over 72fps is just wasted as our visual pipeline is saturated past that point." On the other hand, I'm glad that companies make it possible to show crazy-fast framerates, for the trickle-down effect of cheaper "normal" cards.
The editor even said it is above 72, somewhere in the 100 range. I personally (and most men I know) have a hard time making out a 60 Hz refresh, even. But the majority of women (in a statistically uselessly small sample) could make out 70+
Also note that if you really could see 60, flourescent bulbs would seem to strobe for you. They don't for me, but ask around and you'll be surprised. (It works best with 1 direct bulb. More bulbs, especially on different circuits, can be at different parts of the cycle and meld together.)
But you CAN see a much shorter flash than 1/60th of a second. You don't see in strobe, you see the average of all light in the slice - the "shutter" is open the entire duration. Which is why you see a blur: it's the average of all the images from 1/whatever of a second. This averaging is why the sleepy hollow cardinal trick (and many others) work.
I'm not sure what good 200 fps does when your monitor rate (for a regular monitor, admittedly) tops out in the 80s. I think there are two reasons:
1 mentioned above, is extra capacity. 200 fps average might equal 60 fps during a fight scene.
but another reason is that even if you're displaying only 60 Hz (monitor limit) to have maximum smooth you need a frame refresh every 1/60 of a second, not just an average of 1/60th. And if frames take varying amounts of time to process, which they do, you could be unlucky and have 2 frame refreshes in 1 monitor refresh and then none in another... it would look like 30 Hz because only every other monitor refresh would be an unmodified repeat. This can happen even with BOTH the monitor and fps being at 60 Hz if the fps changes size (sinusoidally, in my example) and they two are not in sync.
FPS are not regular, and the reality is the fps is a measure of speed, NOT a reliable timing device. 200 fps != 1/200th each refresh... the first one after you turn is going to have to make many more changes, so it's going to take a lot longer, whereas many things will be reused in the next one. (this assumes nothing has to move to the card on the bus, which I won't go into) so if that refresh is 4x longer than average you'd be down to 50Hz for that frame. THEN you have to use an integer number of monitor refreshes, so it's going to be 30 Hz as viewed. Too much math, perhaps.
I predict that eventually (probably 1 more generation) many of the objects will be dynamically generated in sync with the monitor refresh. The framerate will be fixed at the (variable) monitor refresh rate. For each frame, one class of objects will be redrawn each time, no more and no less. The problem is that that class has to redraw asynchronously with any other kind of redraw, and that can be bad. But it's good for many kinds of animations... and depending on the architecture it should be no worse in any case.
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Are you people saying that my video card and these "frame rates" are what are probably causing me to lose chess matches online and to never quite get all 40 bonus bugs in the Galaga challenge rounds? Should I be looking for a new card, or will adjusting the resolution help?
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In the midst of battle with body parts and rockets flying everywhere (clarification: my body-parts; someone elses rockets), my rate easily drops down to 90fps. Very rarely, I'll catch it plummeting as low as 70fps or 60fps. I can't really tell any difference between 70fps and 150fps, but anything below about 60fps is noticable to varied degrees.
As long as you can still aim and shoot fluidly, you're fine. Anyone who is still moving fluidly at the heaviest point of graphic intensity shouldn't worry about tweaking every last frame out of their system. Unless there is some revolutionary change in the industry, I don't plan to upgrade my cards for a long time to come (until we see games that drop my frame rate enough that I can notice it). I'm certainly not about to dump a few hundred more on a card just because I can achieve 200fps, when 150fps will more than do.
Besides, what is more irritating is the games with the poor net framework that makes finding a fast server impossible. While Q3's code seems to be sleek (I usualy find a lot of servers averaging between 12 and 30 ping), other games (Unreal Tournement, to name one) rarely have anything below 100 and only a few under 200 ping. Even the sweetest frame-rate can't help poor network performance.
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seumas.com
It's peak frame rate that matters: i.e. the frame rate at the moment that you've got the most number of objects on the screen. Just like you don't want only enough server capacity to handle your average traffic, but instead need a lot extra to handle peak load, so frame rates above 72 ensure that you won't drop below 60 or so even in the most complex scenes.
While on my gameing computer i average 70 FPS there are times that i drop to well below 20 during hard effects (like 5 bodies being gibbed at once). The goal of hardware tweakers is to get the maximun effects while not droping below that critical point of 60 ftp (or 72 as that article clames).
And I promise that i can tell the difference between a computer avereging 72 FPS and 200 FPS.
Sanchi
"They said we couldn't do it [Athlon]... but we built it, we shipped it... and we didn't have to recall it." Rich Heye
The point is, with a faster card, you get better visual quality, be it from FSAA, multiple rendering passes, higher GeoLOD, or just higher resolution. Also, if you get 72fps on average, that might drop noticeably when you least want it to (during big firefights), which would be bad. At 200fps, your performance could take a sudden 64% hit and you wouldn't be able to see it.
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Moderate this up! Hardly anyone (with a clue) argues that they need a constant 200 FPS. The reason you want a base of a couple hundred FPS is so that you're (hopefully) above 72 FPS (or whatever lower number you think is minimal detectable) when there's 25 other guys on the screen all hurling rockets left & right.
60/72 Hz is what we want when we play games, but you generally have to target above that for when your potentially viewable set (PVS) changes dramatically- if you move *really* fast (missile cam), say, or if you just turn your head 90 degrees (and look down a completely different hallway).
A current trend in games is to seperate the rendering cycle from the simulation cycle.
Historically, games have been implemented with a read-eval-print loop like this:
Now, we (FPS, 3D) seem to be moving towards the parallelization of read/eval (simulation) cycles and the print (display) cycles. That way they can be controlled independently: The display can be given just the cycles it needs to provide 60/72Hz, and simulation lives in it's own space. The display routines have their own prediction mechanisms to make sure that they can keep pace.