Face Off: FPS – Enough is Enough

2/10/99 – Dennis “Thresh” Fong and Kenn Hwang

Can’t we all just get along?

Kenn
For over four years now, I find myself every so often getting embroiled in a long-winded, self-imposed debate with someone about exactly “how many frames per second the human eye can see.” Each time, the numbers are always different. “The human eye can only see 24 frames per second.” “The human eye can only see 30 fps.” Be it 30, 60, 100, or so on, folks have always had an inclination to tag an arbitrary number on what we can physically perceive, whether it’s from an overheard reference to film or NTSC framerate. After all, if TV looks smooth at 30fps, then that must be a hard-coded, physiological limit, doesn’t it?

Thresh
Guilty as charged. Way back in the day, I’ve always just listened to what everyone around me was saying, and I took it for granted. I remember that the only time I really took the “greater than 35fps” idea seriously was back when the original 3Dfx Voodoo1 came out, and every single person who had one was posting numbers like 50, 60, and even 70 frames per second! Around that time I stopped thinking “75 fps is way too fast to be playable” and started thinking “faster framerates make the game a whole lot smoother.”

Kenn
Ah, an unbeliever sees the light! It’s refreshing to know that those fast reflexes aren’t inversely proportional to logic. I’ve always maintained that there is no physical limit to what we as humans can perceive. In my humble opinion, like everything else, the ability to perceive such differences comes directly from experience. Once you’ve had a chance to spend some time with 90fps, going down to 40 or 50 fps will be an appreciable difference.The point is, nowadays just about everyone’s had a taste of greater-than-30 fps performance. It’s common knowledge that there’s no 30fps limit on what the eye can see anymore. Also, most people know that 90 frames per second doesn’t a set number of 30fps frames shoot by at 1/3 of a second. The computer renders frames dynamically, so everything runs at the same speed, but more frames are packed into each timeframe (hence the literal term “ninety frames per second”).

Thresh
Let’s not get into that just yet, eager beaver. It’s a whole new can of worms and we’re getting way ahead of ourselves. Let us first tackle the biggest question, “what is the minimum fps needed to enjoy a first-person-shooter game?

Thresh
Without getting too vague, I’ve always thought that most games are playable on any “reasonable” resolution, reasonable being 25-35 fps. Back when you guys were playing with your Pentium Pro 200s, I was running Quake on a Pentium 166, and this was in software, too. In fact, I remember the hot (and only) 3D card to get at the time was the Verite V1000, and while the framerates for that card were significantly higher than what we could get in software, the filtered look was a little too much for me to bear. Obviously, higher framerates will look smoother on screen, but what we’re talking about here is a “reasonable” framerates.

Kenn
You’re forgetting that was then however. As unfortunate as it is for those on a budget, the bar’s been raised on the FPS issue. Faster computers and faster 3d accelerators have made 30fps a thing of the past. Even if it was playable or competitive at the time, it’s far from that now.

Thresh
You need to look at this issue as a whole, you short-sighted mole. Even with swanky new technologies, we’ve still got a big problem (if you can call it that) – all of those software and game developers are also ramping up their technologies. The faster the hardware, the more complicated the software. Hardware’s never been able to keep up with the demands of gaming, and that means that most of us are going to be stuck with less-than-ideal performance at some point or another, whether we like it or not. And I’m sure not going to be giving up a great game just because I can’t get 80fps!

Take television’s 30fps for instance. I don’t doubt that at 60fps, TV signals would be much smoother. However, look at what’s possible even with a hardware limit. If that’s not enough for you, consider a standard format movie. They play at 24fps, a framerate even lower than television! What I’d like to see is if computer animation could someday emulate the processes which make TV and movie animation appear smooth and sharp. This could somewhat relax the heavy burden on “fill rate” and “geometry calculations” plaguing even today’s highest-end systems.

Kenn
Argh, please God, not another “television is 30fps so that’s all you need” punk. All right, let me explain this one more time. NTSC and television appear smooth because they don’t render individual frames. When you record to one “frame” of film or tape, you’re capturing more than that specific instant in time, you’re getting a range. That’s what motion blur is, and it’s the reason why 1) still-shots of fast-action scenes are blurry, and 2) the animation appears smooth despite the “low” framerate.

Kenn
When a PC renders an image for display, that image is a complete, high-quality snapshot of one instant in time, like those little yellow-pad flipbooks we all used to make in grade school. There’s no motion blur (1, although it is technically possible, and 2, Oni’s cool blur effect doesn’t count) to fool the eye into seeing more “intermediate frames”. As you can imagine, insert more frames into the same amount of time, and you have literal intermediate frames, giving a smoother image.I refuse to believe that there’s a “reasonable” limit to what the human eye can see. Our rough estimates are only based on what we’ve experienced, so saying “200 fps is a limit” is completely unfounded imo. Until you reach a point where frames are flashing by faster than the light can travel to your eyes, or more reasonably, faster than the electrical impulses can reach your brain, then let’s talk about limits. However, I think that a person accustomed to watching a 500fps screen is going to notice right away when that drops down to 250fps.

What that means is that everything helps. It’s so much easier to shaft-someone mid-air far range rail-shot with SLI, and that’s the straight truth. While the absolute “minimum” acceptable FPS is a matter of personal tolerance, you’re not going to realize your full potential until you’re able to pull of shots and stunts at the limit of your natural reflex. This concerns both the speed of your fingers and the speed which you can take in signals from the monitor and process them in your mind. For me (and this is a pretty subjective test), it’s between 80fps and 150fps – the point where it became easy (or even possible) to consistently hit and hold a shot on someone in midair. Anything above 150 didn’t make too much of a difference either way.

Thresh
…Um…well it looks like the all-knowing God of Quake has spoken. At least you had the common sense to put down a quantitative number. But listen to yourself. A good minimum FPS is between 80 and 150? Gawd, that’s like 1% of the Quake-playing population. I’d have to say that it’s never been the case with me. There’s no doubt that the higher your framerate, the more updates you get, and the more fluidly you’ll be able to react. Having a faster system is about as much of an advantage as you could hope for, but coming from a modem background with an “average” system, I always felt that practicing (or at least starting off) with a disadvantage is the best way to improve skill.

Kenn
I never said it was a minimum, rather the point at which a difference in framerate stopped affecting my game, which is a pretty important point to cover in a discussion like this.

Thresh
Well, it still sounds a little snobbish to me. That’s what you get when you’re addicted to Winbench scores I guess.

I just look at the entire situation like this: If you’re a biker, you can spend $3000 on a kick-ass titanium ride, or $100 for a Huffy. You get better control, components, half the weight, and more with the expensive bike, but it’s up to you to spend the cash to get that “competitive advantage.” Having it isn’t your fault, and it’s not unfair, but in the end it’s the rider and not the bike that makes the difference, so don’t be surprised if one day someone comes up out of nowhere and burns you on a Huffy.

Kenn
Well, that Huffy is sure going to be a huge determining factor in any race, and I sure wouldn’t include it as an acceptable minimum in any kind of race. I guess you’re right in that depending on how serious you want to be, you’ve got to make an investment in equipment at some point. While 30 or 40 fps will do for most gaming situations, you’ll definitely want to look for more if you take your games more seriously.