So we've had a lot of people ask us questions about frame rate recently.
What affect does framerate have in a game?
How important is it? And why do some games arbitrarily lock it at certain numbers?
This is more of a technical thing than a design issue like we usually cover...
But it's been the subject of a lot of discussion lately, so it's worth looking at.
Just so we're all on the same page, here are the basics.
The illusion of a moving image, like a film or a YouTube video, is created by showing a rapid succession of consecutive still images, like a film reel.
Frame rate is our way of measuring how quickly those still images or frames are shown on-screen.
So when we talk about a game's frames per second, we're just talking about how many times per second the computer updates the rendered image on the screen.
The higher the number of frames per second, the smoother the illusion of motion will appear to our eye.
Now the way our eyes and brains work, we're pretty good at interpreting and anticipating motion.
So we're able to register up to about 12 frames per second as just being a bunch of individual still images
But when we see a succession of images played faster than that - say around 20 frames per second...
...an optical illusion occurs and our brain starts interpreting that series of still images as a single moving image.
And the more frames per second our eye sees, the smoother that moving image will appear to our brain.
So when you see a game's video seem to stutter or pop or lag, that's the frames per second dropping low enough that your brain realizes...
...it's not actually continuous motion it's seeing, but rather simply a series of very quick still images.
Now by the end of the silent film era,
Filmmakers had settled on a standard of 24 frames per second as their default playback rate for several reasons, most of them economical.
What's interesting about this, though, is that 24 frames per second is actually a pretty low frame rate.
And the relatively slow speed at which the film camera records images, compared to the continuous movement of the real world, results in motion blur.
And what's really fascinating is that all of these little artifacts like motion blur that come from shooting at 24 frames per second...
...have become part of what we visually understand as the feel of cinema.
If any of you saw those high frame rate screenings of The Hobbit films and thought that it looked a little weird...
...it's because those were shot at 48 frames per second.
The funny thing is that these high frame rate screenings actually showed a more accurate, crisp representation of what the cameras had filmed.
Recording the action at 48 frames per second ensured that the motion on film would feel more like what the motion had actually looked like on set.
At least, more than other movies.
But there's something stylistic about the look of film at 24 frames per second that has been so powerfully ingrained in our culture...
...that even though the high frame rate versions of The Hobbit movies were more technically accurate...
The result was kind of off-putting to a lot of people. It just felt weird.
Now over time, cinematographers will start to figure out artistic tricks for making 48 frames per second feel more right.
And will start learning what sort of video content looks best at higher frame rates.
Sports broadcasts, for example, tend to feel great with that realistic "I feel like I'm actually there" quality.
For right now, though, at least when it comes to cinema, the feel of 24 frames per second is what we know and love.
So much so, in fact, that many video games go to great lengths to fake having some of those cinematic artifacts, even when running at much higher frame rates.
This is why you see so many AAA games putting development money into making sure that they have stuff like motion blur.
But 24 frames per second is still a little bit low, so for video games, we generally aim for a minimum of 30 frames per second.
Anything lower than 30 frames per second starts to look a little choppy and in fact, it'll actually feel slightly worse to control.
Because games are an interactive medium, and as a player, you're actually trying to react to the images on screen...
...we're a lot more sensitive to frame rate differences in games than we are in passive media, like TV or film.
When that troll in the Fellowship of the Ring movie swings a club at the screen...
...your brain's not trying to calculate which way to dodge, like you would be if you saw a troll take a swing at you in a game.
Having to interact with the moving image on screen suddenly puts a lot more emphasis on fidelity of motion.
And on top of that, frame rate also impacts how many milliseconds it takes for the image on-screen to appear to respond to your button presses.
So if the frame rate drops too low, it can have a significant impact on how responsive a game feels to control.
This is why some players, especially pro players or people who've been gaming for a long time...
...can feel a difference between something running at 30 frames per second and 60 frames per second, especially for action-oriented games.
Not everybody's as sensitive to that difference, and some games benefit from the higher frame rate far more than others...
But when your mind is trying to make split-second decisions and you're really in tune with the game, that increased fidelity of motion can be pretty nice.
Now some of you might wonder why it is we usually talk about games running at either 30 frames per second or 60 frames per second
...rather than the continuous spectrum of everything in-between.
This is actually because of another piece of hardware: your monitor.
Monitors and TVs have essentially been standardized to refresh at multiples of 30 times per second.
So even if your graphics card is rendering somewhere between 30 and 60 - say, 40 frames per second...
...what you'll most likely be seeing when you play is 30 frames per second, because most games try to automatically match your monitors refresh rate.
If you're a PC player, you've probably noticed that VSync toggle in your options menus.
Turning vertical sync off essentially just means you're decoupling the number of frames your graphics card is rendering and how quickly your monitor refreshes.
But desyncing the rate at which your monitor and graphics cards are trying to do things can give you some strange results like screen tearing...
...so VSync is usually on by default.
Anyway, this is why we usually talk about frames per second in multiples of 30.
But that's not to say that getting 45 frames per second out of your graphics card is meaningless.
Or that trying to squeeze a slightly higher frame rate out of your game during development is wasted effort.
Because even if you can't quite hit that 60 frame per second mark, getting the game to run above the 30 frames per second line means that...
...if there's ever a dip in the game's performance for some reason, or if there's ever some part of the game that has to render more than you expected...
...or if there's some other task that hogs the GPU for a moment...
...your player won't even notice, because thanks to the monitor refresh rates and VSync stuff I mentioned before...
...the drop from 45 to 30 frames per second is essentially invisible.
This leads us nicely to the next question: why do some games come out on PC locked at 30 frames per second...
...when many players' rigs might be capable of running the game at much higher frame rates than that?
This could be for a couple of reasons, neither of them good, but... eh.
Most often, it's because there are contractual agreements in place...
...dictating that the developer is not to release a materially different version of their game on PC than on consoles.
So if modern consoles can only run that game at 30 frames per second, that's what PC gets limited to as well.
Yeah, it sucks, I know.
Another reason for locking the frame rate, although fortunately this one's becoming less common...
... is if the game's developers programmed certain parts of the game to run calculations on every frame.
This would make it so that if a game ran at a higher framerate, it would actually mess with the gameplay.
For example, and this would be a case of terrible game architecture for a number of reasons, so it should never happen, but just as an example...
Let's say that an enemy was programmed to check on every frame to see if it should be shooting at the player.
And the game was meant to run at 30 frames per second, so the programmer is expecting that check to happen 30 times a second.
if you ran the game at 60 frames per second, though, the check would happen 60 times a second.
Which not only means a lot more calculations per second that the game is having to run...
...but it also means that that enemy is probably rapid firing like a one-man machine-gun nest.
Now there's been some contention in recent years over certain games being locked at 30 frames per second for aesthetic or performance reasons.
And whether or not 60 frames per second should be considered the accepted standard.
Ultimately, it's a complicated question to answer.
Rendering twice the number of frames per second means literally rendering twice the number of pixels...
...which is a pretty significant demand on processing resources.
For that reason, getting a game to run at 60 frames per second on consoles or a midrange PC can be really challenging.
And almost always requires significantly reducing the density and complexity of the game's other expensive processes.
Like graphics, lighting, physics, or even AI.
Is that a worthwhile trade? Maybe. Maybe not.
From a business perspective, almost every industry study says no.
Better graphics influence sales far more than better frame rates do.
And that's not to say that devs shouldn't still strive to optimize their games' performance, because that's important.
But sales numbers certainly suggest that graphics should be their priority.
In an idealized scenario, all games could easily maintain as high a frame rate as they wanted...
...AND push their graphics, lighting, and shading to the limit without sacrificing anything.
But in the reality of game development, that's never the case, so like I said, it's a complicated question that usually doesn't have an easy One-Size-Fits-All answer.
Often it'll ultimately boil down to what one chooses to prioritize.
Anyway, I hope this has helped to explain some of the basics of how frame rates work.
If you wanna learn more, there are some fascinating technical explanations out there on the Internet that go into way more detail, so I recommend looking those up.
See you all next week!