Spotting, LOS, and LOF explanation

[Battlefront.com]

OK, folks have been asking how LOS, LOF, and Spotting work in CMx2. Last time we talked about this I didn't know because it wasn't coded, but now that it is coded I know

The basic thing you guys need to know about are Action Spots. These are super important to the underlying simulation so you will be hearing a lot more about them in the future. But I don't want to get sidetracked right now, so I'll just give you the short of it. Action Spots are 8m x 8m squares that are dynamically assigned to each map based on terrain based on LOS. They tell CM what spots are important to be in, why, and how they relate to other spots. It is akin to what earlier wargames called "LOS Maps". It is a trick, if you will, to get muuuuuuch faster LOS/LOF information on the fly. It is a must have for a real time game. It also fixes some potentially frustrating micromanagement issues, such as those experienced in Close Combat ("why is that guy on that side of the wall?" "Why won't this guy move over so he can see what the other guys see", etc.). Since, by and large, your Teams will be on a single Action Spot these issues don't crop up.

Action Spots are "mutateable" to account for changes in terrain, such as a collapsed building, crater, etc., so don't worry about that. Action Spots are also important for a host of other features, but again... I don't want to get sidetracked!

Spotting is calculated from Action Spot to Action Spot, LOF is calculated from individuals to individuals. Meaning, if an enemy Squad of 9 men is strung out along 3 Action Spots, and you only have a view of one Action Spot, you have a chance to see the Squad a few men at a time as they pass through. You will not see the ones that have not entered the spottable Action Spot, you will not see those that have already left it. Just the one spot. Now, if the enemy unit decides to park itself in that one spot you can see, well, then in theory you can shoot at all of them.

Assume the Action Spot you are on has 100% clear LOS to the Action Spot the enemy is on. Well, then you are going to have a good chance of spotting them all. Since LOS is free and clear, you also have a 100% chance of shooting at them. Not as an amorphous group, but as individuals. To show you why that is important, assume that there is a cluster of small boulders or debris of some sort. It is enough cover for 5 guys, not 9. This means you'll have a better chance of hitting 4 of the guys (the ones not behind the cover) than the other 5. Now let's change this around again and say that there is a low stone wall just in front of the enemy's Action Spot. All the enemy go prone, you can't see them and can't shoot at them. 2 of them get brave and poke their heads up... fair game for those two only! The 7 that are still lying down are off limits.

How's that sound?

Steve

[ August 13, 2006, 10:59 PM: Message edited by: Battlefront.com ]

[Homo ferricus]

Perfect! I was hoping that that spotting would work a lot more differently than it did in CMX1, and it seems that you guys took full advantage of 1-1 scale representation in squads, awesome! Thank you team battlefront!

[Michael Emrys]

Sounds okay so far. As we know, the devil is hiding in the details, so we'll have to see how this all works out.

Michael

[WineCape]

Elegant!

[Salkin]

Yummy !

[Jussi Köhler]

Yuk-Yuk !

[John Kettler]

Steve,

That sounds like a slick, CPU friendly approach to handling a computation intensive problem which otherwise could really bog computers. Please congratualte Charles for me.

Regards,

John Kettler

[Jussi Köhler]

Too many syllables, please edit your post John.

[lizardman743]

It is oh so tricky!

[hoolaman]

This idea has my official approval.

So LOF is resolved down to as low as ~1x1m? Presumably LOF is very finely resolved for each shooter or funny results may occur ("that guy was behind that rock when he got nailed!, fix or somefink!"). Hopefully LOF and interruptions thereof can be calculated on the fly which will have relevance to rockets and other weapons which have a long time of flight.

The spotting routine sounds like a realistic abstraction that hopefully won't knock anything else out of alignment.

[hellfish]

Sounds very interesting! I can't wait to see how its handled in game.

[hellfish]

Oh, will CMSF model individual soldiers popping up over that low wall? Is there a way to keep them all down and hiding or to have them all popping up at once and firing?

[kipanderson]

Steve, hi,

Just to confirm something you mentioned on an earlier thread but could not promise was included at the time of writing.

AFVs/tanks and such will block LOF both for ordinance and small arms?

In an earlier thread you said your best guess at the time of writing was that tanks would block LOF but not LOS.

Thanks,

Looking forward to CMSF,

All the best,

Kip.

[Battlefront.com]

Yes, LOF is tracked based on where the actual soldier is. I suspect it is a lot finer than 1m x 1m. LOF is calculated on the fly this time, so things like guys hiding behind a moving tank can be simulated this time around (it wasn't possible with CMx1).

Individual soldiers act individually. This means 2 guys might keep poking their heads up while the others stay down. The decision is based on the unit's Commands and situation, just like CMx1. Unlike CMx1 it is not abstracted graphically.

Steve

[Battlefront.com]

Follow up for Kip,

Yes, that is still the case. LOS can not be blocked by moving objects, such as vehicles (actually, that is just about the only thing that is relevant!). The reason for this is that updating the Action Spot map data involves a performance hit. This isn't a problem for the occasional building wall coming down or crater being formed since they are just that... occasional.

Vehicles moving around would require changes to the map every time they moved for every Action Spot they moved to. AND this would have to keep up with the vehicle, some of which can travel close to 60mph. Picture the difference between a couple of shots deforming the terrain with a company of Strykers moving at top speed and you'll see what I mean!

Since LOF is calculated on the fly anyway, it can check for things getting in the way.

At leat that is my understanding of all this complicated stuff. I'm just a caveman, the world of programmers frightens and confuses me

Steve

[Michael Dorosh]

Originally posted by Michael Emrys:

Sounds okay so far. As we know, the devil is hiding in the details, so we'll have to see how this all works out.

Michael

How dare you not slap Steve on the back sight unseen. :mad:

But I have to agree...will eagerly anticipate Madmatt's first public AAR.

[kipanderson]

Steve,

Thanks for the update… sounds good to me… just the job.

The single feature that did eventually get to me and largely kill CMX1 for me.. after many happy years of play … was Absolute Spotting. Suddenly about two years or eighteen months ago I found it too intrusive and unrealistic. Particularly in more open terrain such as desert and the Eastern Front.

The new spotting would by itself have me glued to me PC when CMSF is launched.

All the best,

Kip.

[Battlefront.com]

I've only played around with the new spotting a little bit so far because there is no AI at the moment so the enemy isn't moving around. But I can tell you that it is neat when Unit A spots an enemy unit and Unit B can't target it because it can't see it.

Steve

[undead reindeer cavalry]

do humans block LOF as well?

[Ace Pilot]

Originally posted by undead reindeer cavalry:

do humans block LOF as well?

Just once.

[undead reindeer cavalry]

Originally posted by Ace Pilot:

</font><blockquote>quote:</font><hr />Originally posted by undead reindeer cavalry:

do humans block LOF as well?

Just once.

</font>

[Dirtweasle]

Sounds good to me. A question if you have a moment; How does smoke and/or dust fit into / work with the Hot Spots concept? What if the dust or smoke is moving or being created by something on the moves, as with your example of a Company of Strykers?

[Battlefront.com]

Dust and smoke obscure LOS and therefore LOF to some extent. Depends on what is doing the firing. Thermal sights should be able to cut through that stuff.

Humans blocking LOF... we'll have to see what we can do with that. It's a complicated AI problem since units have to know when, and when not to, hold fire or avoid getting in the way. Tricky stuff. Things like smoke and terrain are simple in comparison.

Steve

[SteveP]

Let's see if I understand this correctly: LOS becomes an attribute of a location on the map -- I assume this location is the center point of a 8m x 8m square. This point has LOS or not to center points of other such squares on the map. That is, LOS is good if there is a clear line between these two points, even if there would be blockage in any other lines connecting any other two points in these two squares. This second type of blockage becomes an LOF block, not an LOS block.

So, since there is still Borg spotting within teams and squads, a shooter (say the LMG gunner in a squad) could "see" a target, but be blocked from firing at it. Or, a tank in one Action Spot could "see" an AT gun in another Action Spot (when the two Action Spots had LOS to each other, but at the same time the tank does not have LOF to the gun. If so, that would like keyholing now, except that the tank wouldn't need the Borg spotting assistance of another unit -- it could do it's own spotting while still being protected by, say, the corner of a building. Do I have that right?

Or is LOS between two Action Spots somehow the collective attribute of all the points in one Action Spot having, or not having, actual LOS to all the points in another Action Spot?

[Jussi Köhler]

If LOS is calculated as a spot, a part of terrain, how will it handle people who are "hull down", i.e. the ground they stand on is hidden but the dirty terrorist rebels or zionist intruders are visible?