How to stat a character with truesight that is blind outside a certain radius?

Question

I'm trying to learn more about GURPS for a future campaign, and I'm working on converting some old DnD characters to get a grasp of how to build PCs. My players will need my help with chargen, so I want to get a good grasp before we play our next GURPS game.

I'm not terribly concerned with making abilities match 1:1, but making some of the signature character traits we homebrewed in DnD work in GURPS. One character in the last campaign was cursed with a supernatural blindness - her eyes burned away, but she gained a limited form of truesight (from DnD 5e). She could see through illusions, see the invisible, and see perfectly in darkness, magical or otherwise, but was completely blind outside of a radius of 60 feet. I also ruled that she could see 360° around her, without needing to turn her head etc, so she could do things observe people nearby while acting inconspicuous. She can't see through walls or anything like that.

So far in GURPS terms, I've got the following:

1. 360° Vision, Panoptic 2 [40 pts]
2. See Invisible (Magical), Truesight [23 pts]
3. Dark Vision [25 pts]

I'm at a loss how to model the 60ft limitation though. What's the best way to work this out? Reduced Range from Powers seems like it's meant to apply to things that already had a range, like the distance you can shoot laser beams or whatever.

Answer 1

There is a power from the Supers sourcebook that might do what you want.

Radar Sense 50pt +1 per hex of range

You have a complete radar image of everything around you. You can perceive shapes and objects, but not colors. Do a vision test to pick up details about an object.

An invisible object or character would still pickup on radar. Also, illusions would be pierced, because they are not touchable.

But to stay safe, lets add an "affect insubstantial" modifer of +20%. This allows our character too see phased (ethereal) characters and insubstantial stuff like illusions, just like true seeing from D&D grants.

For a range of 60 feet this is about 20 hexes. To perceive colors add a +20% modifier, for a grand total of 98 pts.

$$(50_{base} + 20_{range} ) \times 140\% = 98\,\text{pts}$$

But now you can make the character blind (Matt Murdock) because otherwise they can see beyond the radar range. Blindness is a -50 disadvantage.

So our true seeing character has a trait worth 48 points.

Supers ask to define how the character's radar works, because there are ways to counter it. So our radar works by magic. It ceases to function in no-mana areas (see GURPS Magic).

Bonus anecdote: For 28 extra points we can add x-ray to the radar sense.

Answer 2

GURPS doesn't seem to like sharp cutoff for sensory traits most of the time. The exception is adding the Mêlée Attack modifier to them, which is meant to be repurposed for representing really short-ranged senses (usually close enough to reach, though not necessarily requiring a touch), and stealing the Range Limit modifier from Warp (B99, and seems questionable for applying to vision). If softer cutoffs are acceptable, here are two ways of achieving that, both based on the Short-Range (Powers, page 112) which replaces normal SSRT modifiers with a flat -1 per yard of distance (with the base +10 for plain sight, that results in a -10 modifier at 20 yards).

Once you picked one of the above approaches, you may want to choose between the two ways of building the sense:

Applying Modifiers to Vision

Powers: Enhanced Senses page 9 explains how to apply modifiers to normal senses: one point per each 5% value a modifier would normally have. Thus, Short-Range Vision would be a Disadvantage that gives you a mere two points. That doesn't look right. By comparison, stealing the Range Limit modifier from Warp (-55% for 20 yards) and applying it to Vision would give you a Disadvantage worth 11 points.

So the costs look not very favourable, but perhaps the latter option is within an acceptable point range for the amount of inconvenience suffered. You also should retain 360° Vision and See Invisible.

Building a Scanning Sense

Taking Blindness and a Scanning Sense is an alternative approach. Please keep in mind that being an Active Sensor, a Scanning Sense is not hard-capped in terms of range: you can roll to detect things beyond the base range of a scanning sense at -2 per doubling of range (B472). So you'll probably want to still apply the Short-Range modifier (which isn't the same as Reduced Range) to make its sensitivity fall off sharply beyond desired base range. You need extended arc to achieve 360° coverage. You'll also need an enhancement for detecting colours, and possibly LPI or outright supernatural No Signature.

Among the Scanning Senses, the best candidate is probably Extra-Sensory Awareness from page 17 of Psionic Powers, with its 20-yard default base range, supernatural origin, and its similarity to human vision. You also will incidentally be able to ignore electromagnetic invisibility, but may be susceptible to magical invisibility (which you should be able to solve with either a Cosmic modifier, or purchasing See Invisible as you planned to).