LOS Question (bypass LOS)

Will Fleming

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An infantry unit moves from 21L4 to bypass K4 along the K4/K5 hexside using NAM, what is the DRM of the shot from M2 to K4 (K4/K5/L4 vertex)?

A) -2 (-1 ffnam, -1 ffmo) or
B) 0 (+1 hindrance from L4, -1 ffnam)?

21.LOS.PNG

A4.34 BYPASS LOS: Infantry using Bypass are subject to special terrain modifiers and LOS rules. A unit firing at a Bypassing unit does not have to trace its LOS to the target hex center, but has the option to make its one allowed LOS check per attack to either hex vertex along a hexside traversed by a unit moving in Bypass (thus a choice of two vertices for one hexside Bypass, three vertices for two hexsides Bypassed, etc.) instead. Should the LOS of a firing unit reach an Open Ground Bypass hexside vertex unobstructed (see also C.5), that unit can claim a LOS and a First Fire -2 DRM for non-Assault Movement in the open. A wall or hedge in the target hex is not an obstacle to LOS even though the target may be in Bypass on the other side of that same target hex (although its TEM would apply if crossed by the LOS). If the firer traces his LOS to the hex center, it must cross a bypassed hexside (thus usually qualifying for a -2 DRM for Non-Assault Movement in Open Ground) before reaching that hex center or the LOS is blocked. If a unit is using Bypass (including VBM) along a Crest Line, and the obstacle it is Bypassing is on the higher level of that Crest Line, then the unit is also at that higher level (since a Crest Line itself cannot be Bypassed; 4.3).

A6.12 ATYPICAL LOS: Occasionally, the rules will specify that an entire hexside, part of a hexside, or a vertex be used for tracing LOS to/from a firer/target instead of the hex center dot. This occurs during Road use (4.132), Bypass (4.34, D2.32), Climbing (B11.42), Underbelly Hits (D4.3), Snap Shot (8.15), and movement between Rowhouses (B23.71).

A6.7 LOS HINDRANCE: Some terrain types are not uniformly high or substantial enough to be considered a complete obstacle to same-level LOS, and are listed as LOS Hindrance hexes because each one hinders such fire traced through its hex to another hex but not sufficiently to prevent it entirely (see Terrain Chart/Desert Terrain Chart/PTO Terrain Chart). All same-level Direct Fire and spotting attempts traced through (not just into or out of) an effective LOS Hindrance hex are modified by a +1 DRM to either the IFT or To Hit DR, or the Artillery Initial Accuracy dr. The presence of such a Hindrance always negates Interdiction and FFMO. Being in a LOS Hindrance hex [EXC: SMOKE (24.2) and FFE Hindrance (C1.57)] does not hinder the LOS of a firing or target unit; it is only the presence of a LOS Hindrance hex between the same-level firing and target units (regardless of whether either/both are Personnel or vehicles) that forms a LOS Hindrance [EXC: SMOKE and FFE Hindrances are effective Hindrances to LOS even if they are in the viewer or target hexes rather than between them; these Hindrances (24.4 & C1.57), as well as bridge (B6.2), orchard (B14.2), and tower (B34.2) LOS Hindrances and Fog (E3.311) may affect units at different levels]. Unlike range, which is always the least number of hexes from firer to target regardless of LOS, LOS Hindrances are incurred whenever the LOS crosses a Hindrance—regardless of how small a portion of that hex it may be. Whenever a LOS crosses (or goes along the shared hexside of) two hexes that have the same range to the firer, however, only the LOS Hindrance of the hex with the highest applicable LOS Hindrance DRM is counted. Therefore, the number of hexes in which a LOS Hindrance applies will not exceed the range.

B18.1 A graveyard represents a West European style cemetery with densely concentrated stone gravemarkers and mausoleums. Any hex containing gray/white rectangular shapes—such as 12W4 or 21L5—is considered a graveyard hex. It is not the graveyard symbols, but rather the entire graveyard hex (inclusive of non-wall/hedge hexsides) which affects any LOS drawn into or through it.

B18.2 A graveyard is not a LOS obstacle, but it does Hinder same level LOS by adding a +1 Hindrance DRM for every graveyard hex [EXC: A6.7] between the firer and target.
 

General Mayhem

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B.6 I believe suggests B is the correct answer:

B.6 INHERENT TERRAIN: Certain terrain depictions (orchard, crag, graveyard,
shellholes, etc.) and counter contents of a hex (SMOKE, Bridge, rubble, AFV, wreck)
[EXC: Bypass AFV/Wreck (D9.4)] identify the entire hex (inclusive of hexsides) as
having the characteristics of that terrain type. It is not necessary that a LOS actually
cross such a symbol to be affected—mere entrance of the hex (even if only to trace a
LOS to or through a vertex of such a hex) or a LOS exactly along one of its hexsides
(A6.1) suffices. A LOS traced exactly along such a hexside is considered to have
passed through only one such hex—not two—even if that hexside is shared by another
LOS Hindrance hex. If the Hindrance DRM of two such hexes differ, the larger of the
two Hindrance DRM is used.
 

Jeff Sewall

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Excerpt from a recent Q&A for this situation (see Klas' compilation for the full Q&A - rules A4.34, B.6, C.5B, & C.5C):

The larger question would be, when tracing LOS to a vertex made up of a target hex w/out inherent terrain and other hexes w/ inherent terrain, must the LOS pass through the actual hex w/the inherent terrain to be affected by it?
A. The LOS is not blocked. Generally speaking, The LOS must cross the hex (including hexside) to be affected.
 

General Mayhem

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excerpt from above rule for hindrance-

"mere entrance of the hex (even if only to trace a LOS to or through a vertex of such a hex) or a LOS exactly along one of its hexsides (A6.1) suffices."

If the Q and A is contradicting the rule there should be an errata.
 

Jeff Sewall

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excerpt from above rule for hindrance-

"mere entrance of the hex (even if only to trace a LOS to or through a vertex of such a hex) or a LOS exactly along one of its hexsides (A6.1) suffices."

If the Q and A is contradicting the rule there should be an errata.
Take it up with Perry next time you see him. I don't think there's a contradiction.
 

Robin Reeve

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The hex the moving unit is in has no bearing on the fact that the LOS is along an inherent terrain hexside (B.6).
I think that no one would have a doubt if, in place of the Graveyard, there was an orchard or SMOKE.
 
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CTKnudsen

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The larger question would be, when tracing LOS to a vertex made up of a target hex w/out inherent terrain and other hexes w/ inherent terrain, must the LOS pass through the actual hex w/the inherent terrain to be affected by it?
A. The LOS is not blocked. Generally speaking, The LOS must cross the hex (including hexside) to be affected.
Jeff, with all due respect, I think you may be misinterpreting the Q&A. In that example, LOS only touches the inherent hindrance hex at the vertex, and is not traced along the hexside, as in your example. The Q&A is more relevant to a scenario where instead of firing from M2 as above, the unit conducting DFF is in L1. In that case, FFMO would apply.

If your interpretation is correct, it would mean that fire traced along a hexside, regardless of at a hex center or vertex, or how far along the LOS the potentially blocking/hindering hexside was, would not block/hinder LOS at all. And while I might be wrong, it would mean that I have been playing the game really, really, really incorrectly (instead of the really, really incorrectly that is my normal play).
 

Eagle4ty

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The hex the moving is in has no bearing on the fact that the LOS is along an inherent terrain hexside (B.6).
I think that no one would have a doubt if, in place of the Graveyard, there was an orchard or SMOKE.
Exactly, if the Q&A is to stand as you seemingly interpret, it nullifies all such SMOKE rules as it relates to such, not to mention Orchards.
 

Jeff Sewall

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I don't think I'm advocating nullification of all SMOKE rules. :)

Just to be clear, my contention is that LOS that passes *completely* along a hexside INTO a hex that is not part of that hexside is indeed hindered by inherent terrain in either of those hexes. But fire into one of the 2 hexes formed by that hexside is not hindered by inherent terrain in the other hex, regardless of how much of the hexside is traversed by the LOS.
 
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CTKnudsen

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Hmm, I see what you are getting at, and it makes sense to a degree. However, Perry's answer seems fairly definitive - fire traced into/through hexes, or along "inherent" hexsides affects LOS, even to vertices.

I think this is one of those ones, like a lot of the conceptual constraints imposed on bypass (and elevation, and hexside terrain...) by the hexgrid, where we just have to shrug and accept it as part of the game to maintain logical consistency with rules elsewhere. If it helps, imagine that the inherent hindrance does not actually follow a straight 40-meter line, and maybe undulates just enough to give some smattering of cover to anyone moving around a building corner, when viewed from just such an angle.
 

Justiciar

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I disagree. The unit is *in* K4 even though the LOS is traced to the vertex. A is the correct answer.
—mere entrance of the hex (even if only to trace a
LOS to or through a vertex of such a hex)
or a LOS exactly along one of its hexsides
(A6.1) suffices.

You contend the unit is IN K4...then the above still applies in your presentation/case/argument....
 

Jeff Sewall

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—mere entrance of the hex (even if only to trace a
LOS to or through a vertex of such a hex)
or a LOS exactly along one of its hexsides
(A6.1) suffices.
The problem with this is that it is contradicted by Perry's response to the Q&A I cited in post #5. In that example, the LOS is traced to a vertex of such a hex, and the orchard in the "other" hex does not apply.
 

CTKnudsen

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But the Q&A doesn't describe the same situation as the original post, Jeff. Here it is:

QA.PNG

In this case, the vertex in question is N8/M8/M9. Note that the LOS line from P6 only touches palm tree at that vertex, nowhere else. In this specific case, i.e. only the vertex is touched, the LOS is not blocked. But then Perry comes right out and says that if the LOS crosses the hex otherwise, inclusive of the hexside, then the LOS is affected. So vertex only is not enough to affect, hexside is. Which is in line with how hexside LOS works with inherent terrain everywhere else in the rules.

I suppose one could put in a new Q&A with the exact same situation as the one above, but with the Japanese unit in O6 vice P6. This would be exactly analogous to the situation described in the original post. But I wouldn't.
 
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Jeff Sewall

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Of course it's not exactly the same situation. But the response to the Q&A does contradict the bolded part of Justiciar's post #13, which was my point.
 

Brian W

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The way to look at it is that the LOS is traced to the vertex, but the unit is "really" walking between that line and the obstacle. So, the Q&A agrees with the mechanics of bypass movement, and the shot in the OP's question is at -2, just as the LOS is not blocked in the Q&A.

Note that in the Q&A, if the unit were in O6 the LOS would be blocked.
 

CTKnudsen

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Ah - my apologies, it may be that I am too tired for this sort of braining, although that's never stopped me before!

So I think that in the original post, the graveyard hindrance does apply, as despite the fact that the unit is moving IN K4, the LOS is drawn (to the vertex) exactly down the L4/K4 hexside - the Q&A does not apply. Were the firer in the L1 woods, it would be FFMO, as the Q&A pertains.

Agreed, because in that case, the LOS would pass completely through the orchard hex (along the hexside) and into the next (target) hex.
I am so confused now. Do you still maintain that the shot from the original post gets FFMO, despite LOS being traced along the L4/K4 hexside?
 

Perry

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So I think that in the original post, the graveyard hindrance does apply, as despite the fact that the unit is moving IN K4, the LOS is drawn (to the vertex) exactly down the L4/K4 hexside - the Q&A does not apply. Were the firer in the L1 woods, it would be FFMO, as the Q&A pertains.
This seems correct to me.
 
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