The Commander Series Forum

The current definition of crestlines leads to some strange anamolies - if an observing units simply pivots on the spot it changes what it can see and depending on the precise facing of the observer some enemy units that would really be on the reverse slope can be seen. Also, if terrain is modelled with crestlines then why not use them?

Can I therefore put the following up for discussion as a replacement:- If terrain is not modelled with crestlines then use an imaginary line drawn through the centre of the hill perpendicular (or at right angles if you prefer!) to the LoS from the observer to that point.

Can I also suggest that it is crestlines that block LoS - not high ground - otherwise troops in the same side of a ridge would not be able to see each other.

Finally, a pet hate of mine - can cover only be allowed to those units on crestlines and also only against direct fire. As someone recently posted (Gun-Hit I think) the justification for giving all troops on hills cover because of "unmodelled bumps and hollows" (or some such) just doesn't hold water - bumps and hollows would also exist on "level" ground but they are ignored there, so why be inconsistent? And the argument that cover against indirect fire is the result of difficulties in spotting the target is a piece of double-counting since there are separate spotting rules which take that into account (and anyways bombs and shells don't have eyes!).

Please don't misinterpret this post - I'm not having a go at the rules (or the writer!), I'm just trying to help.

Puzzled

I think it's really up to you. If you are playing the rules as written then stick to it, if you want to use your own house rules then that's your own choice.

Our House Rule:
Use actual tabletop terrain line of sight.
Use your eyes or a laser pointer to determine what really can be seen, how much can be seen or not seen and adjust firing factors accordingly.

This system means no drawing artificial hidden crest lines on hills.
---
It's so much easier and faster. A little more real too.
Respectfully,
Bill

Puzzled - I have no real issues with the crestline thing. At first I wasn't sure about whether or not AFV's could be "hull down" or if the "5+ to hit" modifier was for only those behind crests or in front as well. And, a few games ago, a situation arose regarding whether or not enemy units on the same hill top could still see each other or whether you still had to calculate a crest (you do).

All in all, I'm quite happy with the hill rules. As for the 5+ to hit even when you're on the front slopes, there are a hell of a lot of "real life" hills that are covered in bushes, gorse, scree, rocks, ruined walls, sheep enclosures, etc. These would all provide some form of cover.

I guess that the alternative is to do as Bill suggested and use actual terrain LOS.

cheers

John

Using actual terrain height is only a good model if your hills are close to the same scale height as your figures.

When LOS changes due to facing changes, also remember the ground scale does not match the figure scale -- consider that within the area represented by the figure's base, the actual troops are shifting sufficient ground to deploy most appropriately for their new facing.

Mo

Hey Johnboy!

I don't follow your logic:

"As for the 5+ to hit even when you're on the front slopes, there are a hell of a lot of "real life" hills that are covered in bushes, gorse, scree, rocks, ruined walls, sheep enclosures, etc. These would all provide some form of cover."

The same argument applies to level ground - in "real life" it is almost never completely flat and open and it has all sorts of similar obstructions too - but you don't hit on a 5+ then. Why spply the argument to one situation and not the other?

Thanks

Puzzled

Hey Bill

I don't like applying actual LoS to elevation for the reason Mo mentions - the ground scale, terrain scale and figure scale are all different so I belive "real world" LoS is not a good way of determining game LoS in terms of elevation. However I do agree that's it's the best way to deal lateral LoS issues.

Thanks

Puzzled

Hey Mo

"When LOS changes due to facing changes, also remember the ground scale does not match the figure scale -- consider that within the area represented by the figure's base, the actual troops are shifting sufficient ground to deploy most appropriately for their new facing."

That doesn't seem to straighten out the anomolies to me. At the risk of boring you and everyone else I'll try to explain why.

Imagine an observing unit, facing directly north, which is due south of hill. In this instance the existing definition does work - a line running east-west (parallel to the units front edge) through the centre of the hill is a sensible approximation to a crestline and results in the northern half of the hill being out of sight (the reverse slope) and the southern half being visible (the forward slope). With regard to your argument this facing also provides the widest unit frontage relative to the hill.

Now imagine the observing unit pivots forty five degrees to its right (so it is facing northeast). The existing rule now has the crestline running northwest-southeast through the centre of the hill. This means that fully a quarter of the area that was previously (sensibly and realistically IMO) designated as the forward slope is hidden from the observing unit (even though the unit has turned towards it!) and equally a quarter of the area that was previously out-of-sight due to being on the reverse slope is now visible to it (even though the unit has turned further away from it). This is without the observing changing its position and (referring to your argument) with the unit having a narrower frontage relative to the hill.

Lastly imagine the unit pivots ninety degrees to its left (so it is facing northwest). It can now only see half of what it could see when it was facing northeast and can also see half of what it couldn't see then. This is huge change considering that the unit has not changed position and (referring to your argument) the unit frontage relative to the hill has stayed the same.

It appears to me that a significant anomoly could be solved with a straight forward rewording, but if I'm in a minority of one then so be it!

Thanks to all for the replies.

Puzzled

I can see what you mean and I have simply adjusted the test of the rule to mean that the line drawn through the centre of the hill is perpendicular to the LOS of the unit, not simply off its front line.

Chris

Hello Chris!

Haha! A minority of two!

Thanks

Puzzled

Hey Johnboy!

I forgot to mention that if the kinds of cover you mentioned as being on hills are significant enough to be included in the game they ought to be represented by linear obstacles and low area terrain, just as they would be on the flat.

Cheers

Puzzled

BTW the hill you described sounded like those in the Yorkshire Dales - are you a rambler by any chance?

I'd always interpreted as Chris says - mind you, I make stuff up authoritatively all the time

Hi Puzzled - it's a fair point you've raised about rockpiles,bushes, dips, bumps, etc also being on flat ground. But, at the end of the day, if the rules say you're more difficult to hit if you're on any part of a hill, then I haven't got a major issue with it.

Secondly, your in-depth example about how reverse crests suddenly become visible just because you turn to face north-east is very valid indeed. Hadn't thought of that one! And, of course, it opens up a whole new can of worms. Time for some house rules?

And yes, I have been known to strap on a pair of boots and a rucksack from time to time

cheers

John

Just thinking this through to it's logical conclusion. When I deploy a platoon on the ground and face them away from a hill do things on the rear of the hill really become easier to see / hit. I think that Wellington may have been playing house rules when he talked about warfare being concerned with the other side of the hill!

"...the line drawn through the centre of the hill is perpendicular to the LOS of the unit, not simply off its front line."

I think that's a much better way of calculating the crestline too. Can I see him from here? Is the hill in the way or not? Which particular segment of the allowed 180 degree (or 90 for restricted) arc you're looking through shouldn't really effect the answer to that question.

I have also noted this odd effect and just use the following instead:
Bear in mind that the hills I use are stepped hills and thus can be considered as contours. Units on the same contour of different hills may not be able to see each other. If you are using rounded hills then I suggest you treat the base outline as the contour regardless of height.
Draw an imaginery line between the centres of the two units. Measure the length of the line where it passes over the contour and placed at the mid point place a second line perpendicular to the LOS. If the unit is behind the second line then it is out of sight. If the unit overlaps the second line but its centre is still behind the second line then it is considered on the crestline and thus in cover.
We've used this method in all our BKC2 games and it seems to work well.
As for cover on hills we assume the hills don't offer any cover other than for being on the crestline but it would be simple enough to nominate some hills as low cover to provide cover for infantry and the like but not hide vehicles.