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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.
And I don't know many monitors that would even handle that.
Since the only way to render at framerates above monitor vertical refresh rate is (obviously) to disable vertical sync (pausing rendering until the screen is updated), then you'll get tearing effects, as part of the screen is being drawn from data rendered in one frame, and the next part of the refresh uses the next rendered frame.
In fact, this shows that your data's being wasted; say for example 200fps on a 100Hz monitor, only half the data from each frame is actually drawn.
At high frame rates, the tearing effect probably causes the 'blurring' you describe.
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.
you heard it here first.
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What this guy writes is a mixture of secondary school knowledge and flamebait. Yes, he goes in some detail on how our eyes work but he strongly lacks some deeper scientific knowledge. A clear example:
"The visual cortex is where all the information is put together. Humans only have so much room in the brain, so there are some tricks it uses to give us the most information possible in the smallest, most efficient structure. One of these tricks is the property of motion blur."
Some tricks that produce motion blur... However he does not explain any details of what these tricks are. How human brain compresses information is still a question but this guy even does not touch this slightly. Only "tricks of the trade". Sorry people but he is very superficial. I am no expert on these things but I saw books and I know people who would explain more clearly for the layman these things. Once, Scientifc American published an excellent book exclusively dedicated to this problem. I think it would be worth to search for it.
On what concerns 72fps. Is he nuts? I can discern a 60-70 fps picture clearly from a 110 fps! On such level it is still well seen how things go hickcups.
And on what concerns monitors. For me and several people 60Hz is deadly painful! Seat on a 60Hz monitor for the whole day and you surely get some serious headaches (specially on the temporas and inside the eyes). It looks like someone furiously turns lights on and off. On a 72-75Hz it is still visible the flickering. The minimal frequency for such aliens/mutants like me is no less than 85 Hz. And sincerly one gets tired working on such monitor. My good level is 100Hz. Yes there I can work without feeling any stress. Btw. When working, I pass more than 12 hours day in front of the bright head of the computer. In fact, my work turns frequently to 36 hour shifts (like today, I'm in the 17th hour). So guys, maybe I mutated too strongly... >:E
Well, I don't know where this guy took his theories but my everyday work tells me he's nuts. So much for the theory.
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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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.
I worked for a research and development group about 15 years ago. One of our areas of research was frame rates. We discovered that frame rates are a function of age, genetics, ambient light, and a number of other smaller effects. The highest rate we saw before fusion was 78 fps. Some don't see flicker at rates as low as 55 fps. Everyone saw flicker at 50 fps.
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.
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Firstly: Quake3
The game is designed in such a manner that there is always a server and a client, even in single player mode. Quake has this little oddity (which hardcore Quake player use a lot) that allows them to achive a bit more height with certain update ferequencies. And somehow the updates are linked to certrain FPS. For instance: Begin able to just jump normally up onto the megahealth platform without any other aid on the Q3DM13 level has certain advantages. I can only do it with a FPS of 120 and 140.
With an FPS of 140 I can rocketjump higher, and with a FPS of 120 gravity seems to work a little less harder, and I can jump from the railgun to the rocket-launcher platform (and back) on Q3DM6. (Using a combination of circle-jumping and stafe-jumping techniques that exploit some other physics feature - these are so difficult to master that they were left in from previous bugs)
Thus for Quake I need a sustained 120. It is possible in Quake3 to cap the framerate at acertain value, but then you must be sure you can keep it there. Besides, there are certain jerking phenomena with my mouse with has a update frequency of 120 Hz, and my monitor with refreshes at 120 Hz if I cannot seem to keep 120 FPS in quake. (Which makes railing more inacurate)
These things are only important in competitive playing, for which Quake3 was designed.
Secondly: Other games.
Mostly similar to reasons I stated above - Mouse jitter on certain systems, as well as sustaining the same FPS on even high difficulty scenes. Most of the FPS ratings were done with certain detail off, and was only an average. You need about 150+ on average to have >80 on worst scenario.
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.
The article doesn't debunk it. It supports it.
Read up before you post, Tim.It's a known fact that most "super-jumps" (questionable physics be damned) in Quake3 cannot be made with anything less than 125 frame or so.
Jump from the rail over on DM6, the swing jump to get the health in the middle of Tourney 4, etc, cannot be done with lower framerates.
Granted, this has nothing to do with perception, but gameplay is also kinda important.
Most games use this to their advantage, so that when I play Half-Life, my frame rates never go above 72 FPS since my refresh rate is around 72 Hz - this is used to prevent "tearing" when one frame is rendered during the first half of the sweep to refresh the screen and another is rendered later. Going above your refresh rate will actually make your game look worse.
Even if the card is capable of 200fps, it should never actually do that - unless you have a rediculously fast refreshing monitor, you're just drawing frames that you won't see or that will simply tear. Plus, I believe that it's been stated that the human eye cannot discern framerates above about 60FPS anyway. Although it is quite nice to be able to play Half-Life at 1280x960 at a constant 72fps (again, locked to 72fps since anything higher would tear on my display).
You are in a maze of twisty little relative jumps, all alike.
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.