Field of view in video games

In first person video games, the field of view or field of vision (abbreviated FOV) is the extent of the observable game world that is seen on the display at any given moment. It is typically measured as an angle, although whether this angle is the horizontal, vertical, or diagonal component of the field of view varies from game to game.

The FOV in a video game may change depending on the aspect ratio of the rendering resolution. In computer games and modern game consoles the FOV normally increases with a wider aspect ratio of the rendering resolution.

The field of view is usually given as an angle for the horizontal or vertical component of the FOV. A larger angle indicates a larger field of view, however, depending on the FOV scaling method used by the game, it may only affect the horizontal or the vertical component of the field of view.

The horizontal and vertical FOV are calculated from the following equations:

$r={w \over h}={\frac {\tan \left({H \over 2}\right)}{\tan \left({V \over 2}\right)}}$ $r = {w \over h} = \frac{\tan \left({H \over 2}\right) }{ \tan \left({V \over 2}\right)}$

$H=2\arctan \left(\tan \left({V \over 2}\right)\times {w \over h}\right)$ $H = 2 \arctan \left( \tan \left({V \over 2}\right) \times {w \over h} \right)$

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