The Field Marshal's Guide to Widescreen

Megan Fox

Revised and newly-illustrated for 2008!

It may be hard to believe, but there are still some idiots out there banging on about Bioshock's implementation of widescreen being "broken". It's an issue I've covered, and a notion I subsequently dismissed, in a previous discussion.

The situation is simple. You are trying to render a view of a 3-dimensional virtual scene onto a 2-dimension window, namely your computer's monitor. The problem is that computer monitors are available in widescreen (WS) and non-widescreen (which I'll call "standard def" or SD) formats.
Given that we don't want to distort the image by squeezing it, there are essentially two options for how the image that's displayed on a WS device will relate to that on an SD screen. You can either keep the horizontal field of view constant and vary the vertical field of view according to the aspect ratio of the screen, or vice versa.
This is where the contention arises. Let's look at how Bioshock approaches the problem, with the aid of some pretty pictures.



In Bioshock, the horizontal field of view is kept constant, and an SD device (green line) displays more of the game world at the top and bottom of the screen than the widescreen display (red line).

Note that this is similar to what happens when you letterbox a widescreen movie on an SD TV, or even a 2.35 format movie on a widescreen TV, which anyone who's interested in preserving the original theatrical format will tell you is preferable to "pan and scan" cropping.

The difference is that while dvds or TV signals are encoded at a fixed resolution, a computer game is essentially resolution-independent (within the computer's performance limitations). So a computer game doesn't need to worry about black bars at the top and bottom of the screen, and can just fill them in with an extended view of the game world. In fact a similar effect occurs with some movies which are produced in a 1.85 format for widescreen TVs, and then cropped to 2.35 for the theatrical release. So you're actually seeing more of the film on the "narrower" display device.

Some people believe this is unacceptable. Some people believe it is wrong. Some people believe that widescreen implies wider field of view. It doesn't.
For completeness here is the alternative method, keeping the vertical field of view constant and displaying more of the game world on the left and right of the screen on a widescreen display.



Personally I consider the horizontal field of view to be the more important axis, but contrary to what some people might claim that does not mean it should be greater on a widescreen display.
My favourite example is to consider the situation where you have a WS and SD monitor with the same physical width. For example a 17" widescreen and a 19" SD. In that case, why should the horizontal field of view be any less on the SD display? The answer is, of course, there's no reason why it should. If the monitors have the same width, the SD screen has the larger area and so in that case it would make sense for it to display more of the game world.



Just as I concluded in my previous discussion on this subject, there really is no right or wrong solution. It's a matter of personal preference. However, it is wrong to claim that Bioshock's implementation is broken. It plainly isn't broken at all. You might be used to a different implementation, and you might have read some hyperbolic, outraged righteous indignation drooled onto web forums by simple-minded widescreen owners who think they're being short-changed by the developers, but the fact is those people are just too stupid or ignorant to understand the issue they're complaining about.

I was particularly gratified when 2K stood their ground and quite rightly denied there was anything wrong with their code. They even confirmed that they do indeed develop on widescreen monitors and so what you're seeing in-game is absolutely what they intended and not some sort of mistake. Although they did add a "Horizontal FOV Lock option" (note "option", not "fix") as a concession to all the bleating, witless morons.

The next time you encounter someone making unfounded claims concerning Bioshock and widescreen camera geometry, feel free to point them in the direction of this article and then proceed to tut, shake your head and mutter "you idiot" at them in a suitably disdainful manner.