About
There are many possible ways of observing your surroundings, but audiosense, lightsense, gravitysense, magnetosense, olfactorsense and sonarsense are best known. Out of these, lightsense (which is what humans term sight) is by far the most common, but notably ronites use magnetosense instead.
The ability to sense things relies on 4 possible things:
- ambience of the right type for the sense (having light in the case of lightsense)
- signal (contrasting, non-camouflaged object in the case of light, or things making a sound in silence in the case of audiosense). This can be a torch or a sonarsense chirp, helping you to see (or hear), but also showing your enemies where you are.
- clarity (lack of things blocking the sense, such as mist, dust or foliage in the case of light)
- acuity or the degree to which you have the sense.
You might be able to see from the above, that signal is similar to ambience: signal is bringing ambience with you. It might also be clear that sonarsense is the same as audiosense, except the first has a built-in signal component.
Ambience
However the ambience is gained, there are 6 levels (explained in terms of lightsense for easier understanding, but this applies to all senses).
Blinding (0.1)
Blinding ambience is light so bright that it can damage your eyes with long exposure and your lightsense range is reduced to a quarter. This is also rated 0.1(field,rad) in lightsense and 0.1(field,elec) in magnetosense. A sudden exposure to blinding ambience means that you must make a sv([Perception],10)(/SRD/skills/trait/perception) or be blinded for d4 rounds.
Bright (0.08)
Bright ambience is the equivalent of a glary and and cloudless day. This is also rated 0.08(field,rad) in lightsense and 0.08(field,elec) in magnetosense.
Full (0.04)
Full ambiance represents conditions that are well-lit, without being uncomfortably bright. This is also rated 0.04(field,rad) in lightsense and 0.04(field,elec) in magnetosense.
Dim (0.02)
Dim ambience is the equivalent of the half light of dawn, dusk, a dimly-lit room, or night under a clear sky with a full moon. This is also rated 0.02(field,rad) in lightsense and 0.02(field,elec) in magnetosense. Your targeting range is reduced to a half. Perception checks that rely on vision are made at disadvantage.
Dark (0.01)
Dark ambience is the equivalent of night on a moonlit night. This is also rated 0.01(field,rad) in lightsense and 0.01(field,elec) in magnetosense. Your targeting range is reduced to a quarter. Perception checks that rely on vision are made at disadvantage.
Black (0)
Anything equivalent to underground with no light source. The rating is always 0.
Obscurity
We use the term obscurity to mean a lack of clarity. This obscurity may be because of dim (0.02) or dark (0.01) ambience, or it might be due to something blocking line-of-sight, such as fog, smoke, dust or tree foliage. There are two levels of obscurity (again, explained in terms of lightsense)
Light Obscurity (0.02)
Meaning that vision is hampered by either Dim Ambience, or light fog, smoke, dust or tree foliage. Your visual sense range is reduced to a half. Perception checks that rely on vision are made at disadvantage.
Heavy Obscurity (0.01)
Meaning that vision is hampered by either Dark Ambience, or heavy fog, smoke, dust or tree foliage. Your visual sense range is reduced to a quarter. Perception checks that rely on vision are made at disadvantage.
Total Obscurity (0)
Meaning that vision is blocked entirely. Your visual sense is blocked and you have the blinded condition.
Acuity
Acuity is the strength and quality of your sensory ability. This is rated, using a targeting range in each sense that you have (of audiosense, gravitysense, magnetosense, lightsense, olfactorsense and sonarsense). Humans for example, have 20(lightsense), 1(audiosense) and 1(olfactorsense). This means that their targeting range in lightsense (their primary sense) is 20 metres, and any skill check relying on this sense, will have no penalty, so long as the target is within 20 metres.
Targeting Range
When any rule provision says something like: "you can target a creature within your senses", it means that you are able to perceive the creature within the range of one of your senses well enough to target them. For example, if a creature is standing 18 metres from you in full ambience (0.04), and you have 20(lightsense), then you are able to target this creature. If the creature were, instead standing 22 metres away, then you could still target them but the check would be made at -1, or equivalently, their TC increases by 1.
Every increment of targeting range imposes another -1 penalty.
Lowering the ambience reduces the targeting range as previously mentioned. So under dim ambience (0.02) where you had 20(lightsense), you would now have 10(lightsense), and under dark ambience (0.01) you would have 5(lightsense).
Signal
A signal is something that replaces ambience over a volume-of-effect (VoE).
Let's use the example of a torch (flashlight) to make this clear. This torch may have the characteristics:
torch -> 10(cone), 0.04(field,rad), 400(light)
Its helpful to express signals in two ways:
- as an ambience-equivalent, 0.04(field,rad) in the above case, for determining targeting, and comparing the signal against the background ambience.
- as a signal strength, 400(light) in the above case, for working with Perception, particularly perception challenges (PC) at a distance.
For Targeting
This gives you the benefit of full ambience for the first 10 metres. Beyond the VoE of 10(cone), up to 20(cone) or twice the distance, the effect is halved to 0.02(field,rad) and you would have the benefit of dim ambience (0.02), the following increment up to 30(cone), or thrice the distance, is under dark ambience (0.01).
Now, when using this torch, let's say you are in black ambience (0) with 20(lightsense), you would normally be blinded, but because are using the torch we specified above, the black ambience is replaced by the effect of the torch. The precise results breaking up your 20(lightsense) into the torch's effect bands, can be worked out, but it really boils down to limiting your targeting range to the signal effect of the torch, which means 10(lightsense).
The equivalent ronite plasma torches have the effect of 15(cone) 0.04(field,elec), 400(elec), which would perform a similar role for magnetosense.
So signal helps you see, but it may also help your foes to see you (the Perception side). Whether they can see you and at what distance they may notice your torch, depends partly on the strength of the signal, but also on the ambience of the surrounds.
We look to see the difference between the signal strength (0.04), versus the ambience of the surrounds (0 in this case, because its completely dark). Overall, this means that the relative signal strength remains at 0.04. As mentioned above, for PCs its best to express the result as 400, rather than 0.04.
PC over range range is discussed next.
Signal & Perception Challenge (PC)
Perception relies on the signal, particularly, how it stands out from the ambience.
In the simplest terms, if you have 1(audiosense), then you can hear a sound signal of strength 100(audio) 100 metres away, by overcoming a PC of 9.
9 = 8 + 1(audiosense).
If you have 1(audiosense), then you can hear a sound signal of strength 400(audio) 400 metres away, by overcoming a PC of 9.
However, at half that distance you can hear it by overcoming a PC of 8, and at half again by overcoming a PC of 7.
If you have 2(audiosense), then you can you can subtract 1 from the PC, so if you have 20(audiosense), you are certain to hear a sound signal of strength 400(audio) 400 metres away.
All the same things apply to the other senses, so a typical human with 20(lightsense) will definitely see that 400(light) torch, as long as it's shining in their direction.
Perception With More Than One Sense
There are many cases where you can detect two or more signals (movement, noise, smell etc). Rather than have you make a PC for each signal that can be detected with your senses, its easier to just take advantage in a single chk(PC) on your best sense.
Weapon Signal Ratings
The use of most weapons results in some sound. A shotgun produces a huge amount of sound at 1000(audio), the only way someone would fail to hear this would be if they are really far away (more than a kilometre), they are deaf, or there is a great deal of noise in the area.
A rotorflechette is still really loud, but at 600(audio) its not as loud as a shotgun. On the other hand, weapons that are nice and quiet are most unpowered melee weapons, crossbows and straight bows, which typically produce 10(audio) to 50(audio).
Audiosense
Audiosense measures your ability to hear. Unlike the other senses described below, audiosense is omnidirectional. This means that you don't have to have your ears pointing in a particular direction in order to hear something.
Gravitysense
A creature with gravitysense can see an x-ray image of their surrounds, by measuring microgravity variations, attuned to static shapes, locations and motion. Walls are visible but are translucent, and you can pick out what is behind them but the vision is usually dim. Denser objects are more clearly outlined than others. If a chamber behind a wall is filled with water, then people (having a similar density) will become invisible, unless they are wearing something denser, such as armour. Forms of camouflage and invisibility (anything relying on light) have no effect on this sense. This sense does not have any appreciation of colour.
This sense has a range beyond which things are too minute to see properly, which is 20 metres as standard.
Magnetosense
A creature is able to perceive magnetic fields, and are able to observe all objects in terms of their different electrical properties. Poor conductors will appear dark, good conductors light. Magnetic field sources will appear luminous. In areas where there are magnetic fields (such as on some planets), things always appear as if in bright light (the day night cycle on a planet having no effect), but areas where there are only weak fields will be seen as dim light, and areas where there are no fields will appears as black and the creature will be blinded in this sense.
Creatures with magnetosense are especially vulnerable to EMP weapons. When a creature with this sense is exposed to such attacks, they must make a sv(Perception), or be blinded for d4 minutes.
This sense has a range beyond which things are too minute to see properly, which is 20 metres in the case of most ronites.
Lightsense
This sense is the common sense of sight that works by picking up direct and indirect electromagnetic radiation (otherwise known as light). Through this sense, you can see your surroundings as long as they are well lit. This sense has a range beyond which things are too minute to see well-enough to target, which in humans is 20 metres.
Creatures that rely on lightsense can be blinded by bright flashes of light and they must make a sv(Perception), or be blinded for d4 rounds.
They may also be dazzled by bright light when it is directed at them: this is known as obscurity by light.
Olfactorsense
Olfactorsense is the sense of smell, which is weak in humans, but extraordinarily strong in dogs. This sense also stands in for the sense of taste, which operated like smell in creatures like snakes. The sense relies on signal, that is a smell that is distinct in the surrounding environment. If the target is giving off a smell that is the same as the surrounding environment, then they are in camouflage with respect to olfactorsense. The sense also relies on an atmosphere to carry the chemicals that constitute the smell.
The equivalent of colour in this sense is flavour.
Sonarsense
With sonarsense, you perceive things through echolocation via their hardness and density. Although the sense is visual like all of the other, it relies on you creating your own ambience (by emitting you own sound).
As you perceive all objects by their hardness and density, you can identify objects within a room. You also perceive large changes in density and hardness, represented by walls. Anything that represents such a large change, such as a wall, you cannot “see” through. The sense works well in water, because it relies on hardness as well as density, so creatures swimming in water are visible despite being of similar density to the water itself. Forms of camouflage and invisibility (anything relying on light) have no effect on this sense.
The sound you emit will not travel though a vacuum, so you are blind in such conditions. Also, if you are in an aegis suit, you cannot effectively emit the sound either. If you rely on this sense then, you would need an external sound emitter either carried or installed on the outside of the suit.
The typical targeting range for this sense is 20 metres. This sense does not have any appreciation of colour.
Darksense
This enhancement applies to gravitysense, lightsense and magnetosense. Creatures with darksense are able to see as if it is one ambience level better (excepting black ambience). Therefore, in dim ambience (0.02) they can see as if it were full ambience (0.04), and dark ambience (0.02) as if it were dim ambience (0.02), and so on. Unless you are in full ambience (0.04), however, you will not be able to discern colours. You are not able to see in black ambience (0).
Sensitivity
This is a sensitivity to full (0.04), bright (0.08) and blinding ambience (0.1). Many creatures with darksense also have this sensitivity. With sensitivity you are at disadvantage on all skill checks and saves when in full (0.04), bright (0.08) and blinding ambience (0.1) or those you are targeting are in full (0.04), bright (0.08) and blinding ambience (0.1). Also your targeting range is halved.