D&D General "that you can see", "line of sight", glass, mirrors, ~clairvoyance, blindsight, and anything else.

[SkidAce]

... But a laser won't pass through it.

Are you sure?

 

[Paul Farquhar]

Are you sure?

If we are being technical, the beam would be attenuated.

 

[Lanefan]

Sure you can, because a fog cloud is not an obstacle to arrows. But a laser won't pass through it.

Which - and I'm not sure if the write-ups already cover this - would tend to hamper spells involving rays e.g. Ray of Enfeeblement (if it even still exists). It'd for sure hamper the rays from a Beholder's eyes.

 

[DrunkonDuty]

Yet another reason why I like Hero System. It just doesn't have this issue.

 

[Hriston]

So here are some situations regarding a potential target of a potential effect of such a thing as a spell.
1. the target is within range but on the other side of a transparent, solid barrier such as glass.
2. the target is within range but cannot be directly seen due to an inability to turn or due to an obstruction such as a wall but you are still able to view the target due to something such as a local, perhaps handheld mirror.
2. the target is within range but cannot be directly seen due to an inability to turn or due to an obstruction such as a wall but you are still able to view the target due to something such as a large but distant mirror.
3. the target is within range and on the other side of a restriction to vision such as containment but you are still able to view the target thanks to an ability such as clairvoyance.

So let's say that an ally would benefit from the effect of healing word or you want to attack an opponent with a spell such as feeblemind or magic missile - in what situations would these spells still work? To what extent could the missiles be magical? What about nonpersonal targets such as that relating to mold earth? Anything else related to uses of "that you can see" and "line of sight" wording?

First, the spells you mention require a target you can see. I would say that not seeing a target directly but only seeing its reflection, as in your situation 2, is not seeing the target itself, so the spells would not work in that situation.

Second, the target of a spell must not be behind total cover, following this rule:

A Clear Path to the Target​

To target something, you must have a clear path to it, so it can't be behind total cover.​

Total cover is defined here:

Total Cover​

A target with total cover can't be targeted directly by an attack or a spell... A target has total cover if it is completely concealed by an obstacle.​

In situation 1, the target can be seen, so by definition it is not completely concealed by the glass because the glass is transparent. To offer concealment would require at least semi-opacity. Therefore, the spells would work in situation 1.

Situation 3 is not entirely clear to me, but if I'm understanding what you mean by "containment" and "restriction to vision", the spells would not work because even though the target can be seen with clairvoyance, a clear path is not actually present. I.e. it is actually completely concealed by an obstacle of some sort.

 

[Hriston]

Wait...




Holding up a blanket makes you untargettable? If the GM objects, get a thicker blanket? How thick does the blanket have to be to count as an obstacle? How about carrying a wheelbarrow in front of you? I'd call that an obstacle. So the line must be somewhere between them, at the worst.

No, although it might provide concealment, a mere blanket is not an obstacle because holding up a blanket would do absolutely nothing to protect you from an attack. I would also say that you'd have to do more than just hold up a blanket to be concealed by one.

 

[greg kaye]

First, the spells you mention require a target you can see. I would say that not seeing a target directly but only seeing its reflection, as in your situation 2, is not seeing the target itself, so the spells would not work in that situation.

Second, the target of a spell must not be behind total cover, following this rule:

A Clear Path to the Target​

To target something, you must have a clear path to it, so it can't be behind total cover.​

Total cover is defined here:

Total Cover​

A target with total cover can't be targeted directly by an attack or a spell... A target has total cover if it is completely concealed by an obstacle.​

In situation 1, the target can be seen, so by definition it is not completely concealed by the glass because the glass is transparent. To offer concealment would require at least semi-opacity. Therefore, the spells would work in situation 1.

Situation 3 is not entirely clear to me, but if I'm understanding what you mean by "containment" and "restriction to vision", the spells would not work because even though the target can be seen with clairvoyance, a clear path is not actually present. I.e. it is actually completely concealed by an obstacle of some sort.

Those are fair interpretations probably more for spellcasting than other facets of life and I think that the issue of cover is the more persuasive.

On seeing someone/something, if the police etc. asked if you'd done so, then it would certainly be fair to say you'd seen them even if you'd just seen their reflection. Similarly, if the person had been swimming underwater, it could be fair to say you'd seen them, even though you'd indirectly seen their refracted image.

If the issue is sight then it could be considered that a mirror facilitates a rerouting of your line of sight. You can still know where someone is whether or not someone was directly behind, say, 5-foot thickness of transparent glass or a thin sheeting of opaque paper.

 

[Lanefan]

First, the spells you mention require a target you can see. I would say that not seeing a target directly but only seeing its reflection, as in your situation 2, is not seeing the target itself, so the spells would not work in that situation.

Second, the target of a spell must not be behind total cover, following this rule:

A Clear Path to the Target​

To target something, you must have a clear path to it, so it can't be behind total cover.​

Total cover is defined here:

Total Cover​

A target with total cover can't be targeted directly by an attack or a spell... A target has total cover if it is completely concealed by an obstacle.​

In situation 1, the target can be seen, so by definition it is not completely concealed by the glass because the glass is transparent. To offer concealment would require at least semi-opacity. Therefore, the spells would work in situation 1.

Hmmm...you're on to something here.

Had they wanted it to work such that glass blocked spells, wouldn't the bolded have been better worded as "A target has total cover if a solid obstacle completely blocks a straight-line path from you to it".

And I threw the word "solid" in there to leave open whether a blanket provides cover, or a few inches of water.

Situation 3 is not entirely clear to me, but if I'm understanding what you mean by "containment" and "restriction to vision", the spells would not work because even though the target can be seen with clairvoyance, a clear path is not actually present. I.e. it is actually completely concealed by an obstacle of some sort.

How about this: open field situation (no cover anywhere), caster is in Darkness but is using clairvoyance on someone standing not far away but outside of the darkness. Does that count as "sight" for targeting purposes?

 

[greg kaye]

How about this: open field situation (no cover anywhere), caster is in Darkness but is using clairvoyance on someone standing not far away but outside of the darkness. Does that count as "sight" for targeting purposes?

I'd imagine that it could work with a spell like healing word.

 

[Hriston]

Those are fair interpretations probably more for spellcasting than other facets of life and I think that the issue of cover is the more persuasive.

On seeing someone/something, if the police etc. asked if you'd done so, then it would certainly be fair to say you'd seen them even if you'd just seen their reflection.

Fair, certainly, but not accurate. An object and the reflection of that object are two separate phenomena. The object is not the reflection, and the reflection is not the object If an observer is seeing only the reflection, then they are not seeing the object itself.

Similarly, if the person had been swimming underwater, it could be fair to say you'd seen them, even though you'd indirectly seen their refracted image.

There are rules for visual distance underwater that depend on the water's clarity and the relative brightness of lighting in the area. I think those suffice for determining whether a swimmer is seen or not without bringing in how light interacts with the surface of water in the real world.

If the issue is sight then it could be considered that a mirror facilitates a rerouting of your line of sight. You can still know where someone is whether or not someone was directly behind, say, 5-foot thickness of transparent glass or a thin sheeting of opaque paper.

I would say the mirror interrupts your line of sight and that you are seeing an image on the surface of the mirror. Your second sentence here reads like a non sequitur. What does knowing someone's location have to do with the spell targeting rules which depend on seeing the target and it not being behind total cover?