Why does smoke not go down?

You need to be able to draw LoF from the blast focus, which can't be done if the floor is in the way.

 

Line to the blast focus is not the mechanic applied when determining how terrain above the template cuts into the smoke cylinder, though, per the example for smoke and terrain here: https://infinitythewiki.com/Smoke_Ammunition

So. Uh. The actual Smoke rule says the ammo generates a Zero Vis Zone the size of the template and infinitely high, and the zone is basically a form of terrain given where the ZVZ rules are in the rulebook. AFAIK terrain zones, generally, tend to be played as starting on the table surface and extending infinitely upward unless agreed otherwise. Meaning that there’s sort of a good basis for believing that smoke zones are intended to extend infinitely up and down, and the template just marks the location and boundary.

If you put an ITS sat zone template in a building or on a roof, do you treat it as constrained by the building or does the template just mark position and the zone applies both inside and outside the structure?

 

I was in the same believe as @colbrook where before it required uninterrupted line from target to blast focus to be in smoke. Perhaps an incorrect hold over from n3?

But after looking at it, it just seems that it really starts from the blast focus, spreads outwards to fill in the template, and then go infinite in height with any terrain in the way blocking that section of the cylinder. I word it that weirdly because looking at that example under smoke ammunition, the trooper is on a balcony a couple inches high and the example is clear that he is not effected by the smoke. Because of that, the smoke had to fill up the 2D plane first and then went 3D. So if the balcony was on ground floor and so effectively just a 1 inch step, I can't see any difference than the example shown and so the trooper would not be covered by the smoke.

As for does smoke only rise upwards on 3D plane or downwards as well, I don't see anything about requiring zones to be ground floor going upwards and I feel like height is referring to up and not in both directions. So I feel that it is only in that direction.

For at least what I have seen about zones on terrain, most of those not on ground floor have been generally vegetation in planters or other such greenery and those are also applied from that floor to the ceiling or to the sky if outdoors. Because of that I have not played those sat zones/low vis zones going down either. I have yet to play on a piece of terrain that applied a low vis / sat zone that has gone through a roof/floor of a building outside scenario rules.

 

Hello,

I can't find it neither. Only, in page 78, where "smoke" is described...
<<Smoke Ammunition generates a Zero Visibility Zone (see: Special Terrain,
Visibility Conditions, page 134) the size of a Circular Template and withinfinite height. >>

As it is described I think is "clear" that where the template is fixed become the "cilinder base" and for there the smoke "go up". I think the problem here is same as other "questions" done before, vets players who have lived severeal rules editions... So the doubt is reasonable at least.... Is this a change or only something missing while writting it? Sometimes I believe we will have less problems playing N4 if we could forget all about N3 :D

 

Maybe this is pertinent? The third diagram down on the Template Weapons page shows a Jujak on a pedestal in the middle of a circular blast template. The template in that diagram shows a spherical AoE, not a hemisphere radiating up: https://infinitythewiki.com/Template_Weapons_and_Equipment

Since smoke grenades are template weapons they obey the basic Template Weapon rules. It would sure be nice if there was a clear example diagram to reference that covered smoke on a roof with part of the template off the rooftop, seeing as how smoke is one of the weapons that uses a modified form of the template AoE rule...

 

Becareful with the link because the spherical form don't match with how the smoke works. The screenshots from @Harlock are from the rulebook and in this case more accurate to understand the problem and the solution :) Smoke is a cilinder with the template as the "base".

 

For the smoke to go downwards from the surface of the template means you need to read the word "height" in the significantly less common interpretation that "height" is not only measured upwards from a reference surface. It's uncommon enough that Merriam Webster doesn't have it: https://www.merriam-webster.com/dictionary/height

I think the most appropriate interpretation of the word "height" in the case of a volume rising from a reference surface as in the case of smoke is 2b. "the extent of elevation above a level", meaning if the smoke template is placed so that it over-hangs an edge, there will be no smoke below the template.

I assume you meant to say that you no longer determine the smoke's area by drawing LOF from the blast focus?
I had to do a double-take 'cause I read that as saying you don't need to see where you shoot the grenade :)

--

Bonus headache:
What if the smoke template is placed on a sloping surface. Is the height perpendicular to the template or aligned with Earth's gravity? :)

 

I'm not sure about that, check this

You still need to target some place of the table and center the template there. You need to see the target point or declare a speculative shoot.

Cheers

 

Oh no, these diagrams.

These diagrams aren’t even accurate for the purpose impact / direct templates. (Or at least these diagram don’t show the part of the template that is cut off by the terrain)

 

As the rules are written (meant to be read front to end and not individual sections at a time) the diagrams are accurate. You need to remember that the second and third diagrams are describing the rules as they have been explained until that point - the next section introduces the concept of Total Cover from blast focus and shows us this picture:



I honestly think the smoke page's pictures of how smoke propagates are as near perfect as is possible, leaving only the issue of whether smoke goes downwards or not out.

 

Is there anywhere that says you can actually place smoke on a roof or a piece of terrain? All the rules I’ve found only say you pick a point on the game table. The “it can’t go down” argument is irrelevant if the template must be on the game table. I personally think that’s overly restrictive, but it might be why we can’t find it.

 

@Harlock Yes, those diagrams also exist. Which is not actually pertinent to the point I was making.

My point was about the contrast between the “pure” version of a template’s AoE and the “practical” version of a template’s AoE. The initial diagrams are about the former, subsequent diagrams are about the latter.

We have a “pure” circular template (it’s a sphere) and a “pure” blast template (a cone with a rounded small end and hemispherical large end). We are never shown a “pure” cylindrical template, just the practical version from the smoke examples.

If you compare the pure sphere and the practical hemisphere of the circular impact template, the later diagrams don’t show the AoE if the target were midair (hit by a missile ARO while jumping, for example), but the earlier diagram tells us that the area immediately beneath the jumping model would be within the template.

I don’t find the argument that the later diagrams are the only relevant ones to be very strong.

Where does it actually say that though? It doesn’t seem to anywhere.

All the rules actually tell us for smoke’s area is that it’s a ZVZ with infinite height, the diameter is the same as a circular template which generates it, it’s centered on the target point of the smoke weapon attack, and terrain cuts into it based on verticality rather than referencing a blast focus. The concept of the zone emanating vertically from the template isn’t explicitly stated.

It’s worth noting that even if smoke doesn’t emanate downward, only upward relative to a plane at the same height as the target point, any model beneath that’s tall enough counts as fully “inside” the smoke anyway. Smoke on a ladder 2” up the side of a building will fully hide a S7 TAG that walks underneath and sticks its head into the AoE cylinder, even if the S2 trooper right next to it is fully outside the smoke and standing on the same surface.

 

Did you try the rules? https://infinitythewiki.com/Smoke_Ammunition

It is even labeled as IMPORTANT!