FOV vs POV, we have been doing it all wrong! (game changer)

Discussion in 'General Discussion' started by green serpent, Jul 31, 2021.

  1. green serpent

    green serpent Registered

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    Yes I do totally agree with this. I think a common misconception that it's wrong comes from viewing from a "wrong" point of view such as watching a replay, or having your seating position wrong.

    This is a common theme in photography also, people think that wide angle "distortion" is a property of the lens, but it's actually a property of the perspective (not to be confused with barrel or pincusion distortion, that is ACTUAL distortion). Not that the viewer of the photo doesn't see distortion - they do - but it's because of the perpective and angle of view of the lens.
     
    Last edited: Aug 2, 2021
  2. green serpent

    green serpent Registered

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    He has a point, just a bit abrasive and has no filter!
     
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  3. doddynco

    doddynco Registered

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    I'm struggling to understand this Lazza can you please help me.

    So from what you're saying, a curved monitor (take the Samsung G9 with its absurd curve) is incorrect when using the standard way of calculating vertical FOV? and instead the game video output needs to be warped to something like the red line to correct for the closer edges? Untitled.png
     
  4. Comante

    Comante Registered

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    The peripheral distortion is pretty small, all considered and most of the time you see it with your peripheral vision, it serve his purpose to give more immersion , and to (maybe) make feel vehicle motion better. I would not worry to correct it.
    ps: the distortion you need to apply would be the opposite of what you draw. a barrel distortion would correct it : screen nearer ---> image smaller to compensate.
     
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  5. Lazza

    Lazza Registered

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    What Comante said.

    I can't be bothered drawing diagrams or whatever (and I'm not reviving the old FOV thread that stretched to many mannny pages of explanation and disagreement), suffice to say the game projects onto a flat plane. Multiview projects onto 3 separate flat planes. So when you view on a flat screen at the correct distance and orientation, you see the virtual world with correct perspective. Since our virtual world is scaled correctly, that means you see realistic objects.

    The game provides no options for curved screens (I don't know technically how difficult it is to 'switch' to a particular curved output, either traditionally or with more recent hardware and drivers) so any curved screen will create some distortion, and the ultra curved screens I think you're referring to would be worse. At least that one you can still enable multiview and cut up the distortion into smaller pieces, and chances are you'd barely notice. To be fair this distortion would be quite minor and not really something to be too concerned about - I just like to correct people who I think mistakenly believe the game uses spheres internally and therefore a flat screen isn't quite right.

    Big screens that allow for proper perspective and still having a decent field of view are still relatively recent; and even now most people play games like FPS with higher than real FOV for the extra awareness it gives you. So we're all used to playing with distorted views, and I can see how people might assume that's a flat screen limitation.
     
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  6. doddynco

    doddynco Registered

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    So veriticle fov is for the center of the panel only . I.e in game, if you were to drive up to a rectangular billboard, and look at it directly from the front, the top edge would conform perfectly to the top edge of the monitor.

    If the vfov was continuous across the width of the image (spherical fov), the corners of the square billboard would be off the edge of the monitor and so incorrect for a flat panel. But this would actually be correct for a perfectly conforming curved panel in my opinion.

    @Comante My image warp image is correct because i'm talking about how the image must be warped to correct this distortion, whereas I think you're talking about where the image must be trimmed to, and then stretched to fit the panel. So I think we are saying the same thing in a different way.

    I think I understand this now - thank you once again everyone.
     

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