Experienced Points

Experienced Points
The Great Framerate Debate

Shamus Young | 27 May 2014 19:00
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30fps vs 60fps

At the same time, we didn't really have the technology or desire to broadcast 60 unique images a second. So instead we recorded television shows at 30 frames a second, and then smeared those 30 frames over 60 updates using various schemes that sound awful but seemed to work out fine in practice. This became extra fun when we put feature films on television. Films were recorded at 24fps, which doesn't divide nicely into 60fps the way that 30fps does.

This all worked out well enough until the age of video games, when your framerate became this variable thing. If the computer slowed down, then you might not get many frames a second. If the computer was fast enough, it might be able to provide a completely unique image for every single refresh cycle of the monitor, which is something you couldn't get from television and movies.

Remember that regardless of framerate, refresh rate is a fixed, immutable thing. If a programmer goes insane and makes a game that runs at 120fps, then half of the frames will simply be lost. You'll draw a frame, show it to the user. Then draw a frame, but the physical monitor isn't ready to refresh yet. Then you'll draw another frame, and that one will get shown.

If a game runs at 30fps, then half the frames will be repeated. You'll draw a frame and show it. Then you'll begin the next frame. When you're halfway done, the monitor will be ready for a new one. Since you don't have one ready yet, it will just re-use the previous image. Then you finish the frame just in time for the next refresh.

Note the uneasy case where (for whatever reason) the game runs at something oddball like 40fps. You draw a frame and show it. Then you're only two-thirds of the way done when the refresh comes, so it repeats the previous image. Then you finish an image, but the refresh isn't ready yet. Then when the refresh happens the current image is a bit old, but the new one is only one-third done. Then on the next cycle the frame and the refresh are in sync again. The result is this strange stutter-step where it feels like the game keeps shifting between 60fps and 30fps.

Quake 1

This sounds horrible, but whether or not it bothers you (or if you even notice) depends a lot on both your hardware and your wetware. When I was 27 and Quake was new-ish, I remember noticing the difference between 30fps and 60fps as I geeked around with my hardware and graphics settings. Today? I'm 43, and anything over 30fps is wasted on me. I can barely tell the difference, and it doesn't start to bother me until it gets below 20.

That's another thing about this debate over console framerates: It's all very subjective. Sure, 60fps is, in a completely objective and technical sense, better than 30. And 720p is objectively worse than 1080p. But how much of a difference it makes depends a lot on who you are and where you game. How large is your screen? How far are you from it when playing? Are you directly in front of it, or slightly off to one side? Where are the lights and windows in the room? Do they create a bunch of glare? How old are your eyes, and are you the kind of person who is really "sensitive" to framerate? Do you play cautious and slow-paced games like Splinter Cell or Thief, or do you favor lightning-fast online multiplayer? Do you play for long sessions or short? Are you wide awake or at the tail end of the day when you game?

All of this impacts how your eyes perceive the game. A lot of the debates between people insisting that framerate and resolution are SO IMPORTANT and the people saying they're MEANINGLESS comes down to the difference between playing in a dark room two meters from the screen or a bright office where the monitor is right in your face. It's not that some people are lying, or delusional, or haters of one platform or the other. It's that their gaming situation is likely very different from yours.

So before you wade into the debate, ready to explain to everyone on the other side just how wrong they are about 1080p and 60hz, just remember that it's all subjective and not nearly as important now as it used to be. (Although if VR headsets take off framerate will become more important than ever, since frame-skipping on a screen strapped to your eyeballs can be a ticket to puke city.) In the long run, frame rate and resolution isn't nearly as important as price, games library, and usability. All the resolution in the world won't make a terrible game fun, and people still love the original Thief games, even though their graphics are horrible to the point of comedy. Just keep a sense of perspective.

Shamus Young is a programmer, a novelist, and a blogger.

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