Cave to lower level LOS

Will Fleming

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Orange by me as my opponent and I both think this is the key section.

G11.5 LOS: LOS to/from a cave is traced to/from the cave hex's center dot and the cave's level, but can exist only if traced entirely within that cave's CA (exclusive of its CA Hexside vertices only if the cave is IN a Depression; see B19.51). Hence no LOS exists between different caves in the same hex, nor between the Aerial and cave Location(s) of the same hex, nor between a cave and the above-ground Base-Level Location of its non-Depression hex. Barring other LOS obstructions, LOS may be traced within the CA of a cave in a non-Depression hex to/from an elevation lower than the cave's if its Entrance Hex contains no terrain (including a Crest Line) whose obstacle height along that LOS is > that cave's level. No LOS ever exists to/from a Cave Complex, but always exists between units in the same Complex. If a cave's CA Hexside is also a cliff hexside, no LOS exists between that cave and a Climbing unit at a vertex of that CA Hexside and at a different level than that cave.


Can the Japanese unit in the cave (level 2 cave, level 3 hex) see the American unit (level 1)?

13380
 

klasmalmstrom

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I think that LOS is clear. NRBH, but is not this situation covered in one of the examples?
 

Sparafucil3

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I also think it is clear. There is an example (G11.5) which refers us to the G11.12 diagram. There is definitely an LOS N9, O9, O10, and P9. The hex P9 is a level 2 hex. The LOS passes through there. That hex's elevation (level 2) is not greater than the Cave's elevation (level 2) so I also think the LOS passes over that crest line. This isn't exactly the same situation as in the example though. The hindrance of the Crag would apply though. -- jim
 

Pacman Ghost

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Will's opponent respectfully disagrees :)

If O11 were a normal Level 2 hex (with no cave):
13381
LOS would be blocked to O9 and P8:
B10.2: A lower level unit may trace a LOS into only the initial Crest Line hexside of each level above it. Likewise, a unit may trace a LOS to a lower level only if the higher unit traces its LOS through a Crest Line as it leaves its hex and this LOS never recrosses another Crest Line of the same or higher elevation
However, going back to the original map with a cave in O11, Will's quote from G11.5 allows LOS to come out of the cave and through the Entrance Hex to a lower hex:
G11.5 ... Barring other LOS obstructions, LOS may be traced within the CA of a cave in a non-Depression hex to/from an elevation lower than the cave's if its Entrance Hex contains no terrain (including a Crest Line) whose obstacle height along that LOS is > that cave's level.
i.e. there is LOS from a cave in O11 to O9.

But going to P8, the LOS goes through P9, and so B10.2 kicks in, since G11.112 is clear in stating that the cave exists on Level 2:
G11.112: [If the Cave counter is set up] in a non-Depression hex and its CA Hexside is a non-cliff hexside or a one-level cliff, the cave’s level equals the Base Level (or Crest level — whichever is higher) of its Entrance Hex
The way I read it, the G11.5 clause gives an exemption to a cave's Entrance Hex, but after that, normal LOS rules apply. A unit in an O11 cave shooting at a unit in P8 isn't "on the edge of the plateau", so to speak, and so LOS is blocked.
 
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Pacman Ghost

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There is an example (G11.5) which refers us to the G11.12 diagram. ... This isn't exactly the same situation as in the example though.
Yes, the G11.12 diagram doesn't represent our situation, where the LOS comes out of a cave at Level X (i.e. in a Level X+1 hex), through the Entrance Hex also at Level X, through another hex also at Level X, then into a hex at Level X-1.
 

Sparafucil3

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Will's opponent respectfully disagrees :)

If O11 were a normal Level 2 hex (with no cave):
View attachment 13381
LOS would be blocked to O9 and P8:
Agreed, if we weren't talking about a Cave and the hex was level 2, the LOS would be blocked.

However, going back to the original map with a cave in O11, Will's quote from G11.5 allows LOS to come out of the cave and through the Entrance Hex to a lower hex:

i.e. there is LOS from a cave in O11 to O9.

But going to P8, the LOS goes through P9, and so B10.2 kicks in, since G11.112 is clear in stating that the cave exists on Level 2:


The way I read it, the G11.5 clause gives an exemption to a cave's Entrance Hex, but after that, normal LOS rules apply. A unit in an O11 cave shooting at a unit in P8 isn't "on the edge of the plateau", so to speak, and so LOS is blocked.
Your point about the Entrance Hex is well stated. I still believe there is room for both Interpretations although I tend towards your line of reasoning. Perhaps wait for something from Klas or submit a Q&A. Good question though. I don't look at the Caves section of the rules enough. Regards. -- jim
 

klasmalmstrom

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Now I have checked the rules, and I could not find any examples covering this. But after seeing the image - without sun glare on the phone outside :) - it does look like the hill in P9 would block this LOS.

Think the red text is the key here.

G11.5:
"Barring other LOS obstructions, LOS may be traced within the CA of a cave in a non-Depression hex to/from an elevation lower than the cave’s if its Entrance Hex contains no terrain (including a Crest Line) whose obstacle height along that LOS is > that cave’s level."
 

CTKnudsen

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Ok, I'm not an ASL spelunker, and I'm probably missing something, but this seems a bit off to me.

The example in post #4 with O11 as a level 2 hex clearly has no LOS because of the plateau effect, no problem.

There is nothing in O11 with an obstacle height greater than 3, allowing LOS to be drawn downward out of the hex, agreed.

I disagree that the cave is at level 2, however. O11 is a Level 3 hex, and G11.112 says that the cave is at either the base or crest level, whichever is higher. Since the crest level of O11 is 3, then the cave must be at level 3. Therefore, as far as I can tell, the cave is treated as being on the lip and can see down the continuous slope to O9, and past the crest line in P9 to P8, as non-cliff crest lines have 0 blind hexes at less than 5 hexes range.
 

klasmalmstrom

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O11 is a Level 3 hex, and G11.112 says that the cave is at either the base or crest level, whichever is higher. Since the crest level of O11 is 3, then the cave must be at level 3.
G11.112:
11.112
in a non-Depression hex and its CA Hexside is a non-cliff hexside or a one-level cliff, the cave’s level equals the Base Level (or Crest level—whichever is higher) of its Entrance Hex;

The Entrance hex is O10 - not O11.
 

CTKnudsen

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Aha! Darn MMP, putting important stuff at the end of paragraphs! Yes that clears it up, no LOS to P8.

Thanks Klas - maybe I should get off my duff and finally try a cave scenario...
 

Will Fleming

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Dang you ASL community! I had that hex bore sighted! :)

We came to the same conclusion after I got put into some kind of medeval torture thing with iron, flames and a lot of my blood draining on the floor. Took it for 2 hours before giving up.
 

Pacman Ghost

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We came to the same conclusion after I got put into some kind of medeval torture thing with iron, flames and a lot of my blood draining on the floor. Took it for 2 hours before giving up.
Yah, and all that just to shoot at a lousy 2nd-line 2-3-6 half-squad :-/

But it was kinda entertaining listening to you flip through the rulebook, trying to justify the shot. The torture thing was just icing... :)
 
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nekengren2

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I think I finally understand.
So if I was to summarize in a way mere mortals could understand..................

LOS from a Crest Cave always crosses the Cave Entrance hex and follows all normal rules for LOS across Crest Lines (B10.2).
LOS exists to lower levels if the LOS crosses ONLY the Cave Entrance hex without LOS obstacles (G11.5).
 
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