HUD Stretch
The HUD is the 2D overlay seen in games, and often contains ammo count or weapon, health, revs or speed, depending on the game. This can behave in a few ways - it can either remain the same size regardless of resolution or aspect ratio (this behaviour is considered ideal), or it can change size and stretch as the screen gets wider.
In multi-monitor setups, the HUD can either be spanned across all three screens or centered on the centre screen. Note that spanned HUD does not automatically mean stretched HUD - a spanned HUD can either retain the correct shape and size but simply be located on the edge, or it can be stretched in shape as well as being spanned. I'm not sure I have ever seen a centered HUD that is stretched compared to 4:3 aspect ratio - usually if the developers have taken the time to center it on the centre monitor, they have also taken the time to make sure it doesn't stretch.
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HUD: Stretched
Here is an example of HUD stretching. You can see that as the aspect ratio gets larger, the HUD starts stretching across the screen. Circles are no longer circles, they become ovals.
4:3 Resolution - You can see the circle components in the HUD are round.
16:10 Resolution - The circles start turning into ovals as the HUD stretches.
16:9 Resolution - The stretching is very evident as the aspect ratio gets wider.
Comparison of all 3 next to each other.
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HUD: Not stretched
Here is an example of a HUD with no stretching. You can see that as the aspect ratio gets larger, the HUD stays the same size.
4:3 Resolution - You can see the circle components in the HUD are round.
16:10 Resolution - Although there is more space between the HUD elements, the elements themselves retain their proper shape.
16:9 Resolution - Still the HUD elements retain their proper shape.
Comparison of all 3 next to each other.
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HUD: Multi-monitor
Here are some examples of multi-monitor HUDs.
Spanned
Centered
Stretched
