[Basic] Disadvantage of the Week: Restricted Vision

[johndallman]

Restricted Vision [-15 or -30] is a mundane, if unusual, physical disadvantage. You have a much more restricted arc of vision than normal, which has important effects in tactical combat. This disadvantage appeared at GURPS 4e.

Someone without this disadvantage has three “front” hexes on a battle map, two “side” hexes, and one “back” hex, as illustrated on p. B385. They have a 120° arc of vision without turning their head, and a 30° arc of peripheral vision on either side of that. They defend at -2 against attacks from their side hexes, and get no defence against attacks from their back hex. Attacks into side or back hexes must be Wild Swings, which can only succeed on a roll of 9 or less.

No Peripheral Vision [-15] means that you have only the basic 120° arc of vision. The hexes that are normally side hexes become back hexes.

Tunnel Vision [-30] means you have only a 60° arc of vision. Your only front hex is the one straight in front of you, and the hexes on either side of it are side hexes.

This disadvantage is mostly imposed by equipment, such as diving gear, gas masks, the more protective kinds of low-tech head armour, early space helmets, night-vision goggles and sights, and face armour for horses. Powers: Enhanced Senses adds more detail and Psi-Tech has sight enhancers that limit arc of vision. Steampunk 2 points out that binoculars and telescopes limit arc of vision while in use, and Tactical Shooting does the same for Aim actions. Ultra-Tech helmets don’t limit arc of vision, but binoculars and telescope still do.

I’ve once tried to make use of this disadvantage, but the GM pointed out that since we don’t usually play with a battle map, running it would be very hard. I had been planning to use it as a stage in buying off Temporary Disadvantage (Blindness) on a power, but settled for taking perception
penalties and gradually buying them down.

Has this disadvantage been interesting in your games?

[Phil Masters]

It is very much a disad for games that use a tactical map. As I don't, I'd probably have to prohibit it, but fortunately nobody ever seems to ask. It is quite difficult to justify for a mundane character, though of course there are mundane medical conditions that cause it.

(I'm amused by stories of people who are both registered blind -- okay, partially blind -- and driving license holders. The UK license qualification has a vision requirement, but doesn't, or didn't, include any specification about peripheral vision.)

The stuff about binoculars and telescopes from Steampunk 2 came from somewhere else, but I forget where; probably a 3rd edition book. It makes the point that there are good reasons to switch from spyglasses to binoculars.

[WingedKagouti]

Originally Posted by Phil Masters

It is quite difficult to justify for a mundane character, though of course there are mundane medical conditions that cause it.

Usually those conditions are preludes to more severe loss of vision, and I did go to school with a person who had a severe case of Restricted Vision (he had to manually hold his eyeball still to focus on something). But for most characters with vision issues I'd go with Bad Sight or reduced Perception instead.

[Bruno]

The first thing that comes to mind for real-world biological Restricted Vision (rather than equipment-imposed) is macular degeneration, but that's generally loss of the center of field of vision first, rather than the edges. I don't think the character gets their Side hexes upgraded to Front ones though, they're just left with Side hexes and a need to learn compensating techniques.

Re: driving with Restricted Vision, Anecdotally, I know of two people with severe macular degeneration that a) evaded getting their license taken and b) continued to drive even when reduced to only being able to use the peripheral vision on one side. They both had the "common sense" to do it on quiet back roads on quiet times of day at low speeds, but yikes.
They both did get caught eventually (thankfully).

[whswhs]

Originally Posted by Bruno

The first thing that comes to mind for real-world biological Restricted Vision (rather than equipment-imposed) is macular degeneration, but that's generally loss of the center of field of vision first, rather than the edges. I don't think the character gets their Side hexes upgraded to Front ones though, they're just left with Side hexes and a need to learn compensating techniques.

I have a text box in Enhanced Senses that provides rules that could represent this, though I intended it primarily to represent the effects of blinding lasers and other intense light sources.

[ericthered]

When I think of this disadvantage, I think of low-tech helmets.

I don't think I've ever imposed this disadvantage on someone wearing a helmet though. Or seen it used in play.

[evileeyore]

Originally Posted by ericthered

When I think of this disadvantage, I think of low-tech helmets.

I don't think I've ever imposed this disadvantage on someone wearing a helmet though. Or seen it used in play.

I have, specifically the helmets issue. And I've imposed it in play with higher TL games when helmet sensors take hits and reduce FOV.

Sure, radar still helps to show where enemies are, but not what they are doing...

[Dalillama]

Retinitis pigmentosa is a congenital condition that can cause loss of peripheral vision, sometimes leading to blindness.

[Phil Masters]

Wikipedia has a long list of potential causes, though a lot of them are psychological or short-term.

The fact that adrenaline surges can trigger the effect suggests that one could semi-realistically have a character with things like Combat Reflexes, high Pain Threshold, and Striking Strength, with Temporary Disadvantage (Tunnel Vision).

[whswhs]

Originally Posted by Phil Masters

The fact that adrenaline surges can trigger the effect suggests that one could semi-realistically have a character with things like Combat Reflexes, high Pain Threshold, and Striking Strength, with Temporary Disadvantage (Tunnel Vision).

I have a power in Enhanced Senses the combines Telescopic Vision and Tunnel Vision, inspired by a scene in the Mahabharata.