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At the moment i use 45 degree angle for my gluPerspective(). Is this the correct angle to make the rendering look realistic in how humans perceive it? Also there is an issue with the window aspect ratio, for example 2:1 window will make 45 degree angle look more like 80 degree angle on a screen with 3:4 ratio etc. So the window size changes the perspective as well.

So what is the correct window size ratio and field of view angle for making a game look most realistically compared to how humans perceive the world?

Dan Rigby
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Rookie
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3 Answers3

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Unless you're using some kind of wrap-around setup, a single monitor isn't going to fill up the entire field of view of the human eye, which is usually nearly 180 degrees horizontally (of course it varies from person to person). If you tried to render something that wide, it would look weird -- the scene would appear to stretch out excessively toward the edges. Set the FOV to 120 degrees or so and you'll see what I'm talking about.

So instead of considering the human eye's FOV, you usually just draw imaginary lines from the user's head to the edges of the monitor, and take the angles between those. Of course this varies from desk to desk, monitor to monitor, so it's something of an artistic decision. 70 degrees vertical is decent place to start with. Assuming the game is running full screen, you're basically at the mercy of the monitor itself for the aspect ratio.

Nathan Monteleone
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    Just a side note: That stretching mentioned comes from the way a affine projection works. But there other projections, like fisheye, mercator or such (sometimes referred to panoramic projection), which look very appaling even for large field of views. – datenwolf Dec 14 '11 at 16:20
  • @datenwolf Good point. Looks like you can pull that sort of thing off with a render texture mapped onto a quad... – Nathan Monteleone Jul 09 '12 at 18:26
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    @Datenwolf Did you mean to type "appealing", or "appalling"? –  Oct 17 '14 at 07:27
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In general, unless you have very specific needs, you should give the user the option to change the FOV as they see fit.

You also generally do not want to have your monitor's FOV conform to the human range of FOV. After all, the monitor only covers part of a human's visual range; even if they're not paying attention to anything else, they still see everything around it. Most people are fine with having their monitor be a portal-like view of a world.

Nicol Bolas
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    +1 for "you should give the user the option". Ask any FPS player, FOV trumps realism. Let the player choose what works for them! – BentFX Dec 14 '11 at 18:09
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its around 87

most games seem to use a random center point, so eye to monitor edge is not correct either.

there should also be an adjustment for depth so the screen appears to be no more than a glass pane.

you know when you find one that works, your brain takes it all in very easily and your aim will be perfect as your muscle memory can react instantly.

(guess what, I'm not fine with a portal view :)

user5357609
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