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Pteradon
Jan 17 2010, 16:09
Hello,


This isn't an addon request.
I'm just curious why Arma2 use only 6 digits coördinates.

When i was in the army, we used only 8 digits coordinates + 2 letters for
pointing wich section of the map.
Correct me if i'm wrong, i thought this is standard for NATO troops.

example: AJ 2145 3857

A 6 digit coördinate is to 100 meter accurate,
an 8 digit coördinate is accurate to 10 meter.

For reading the coördinates on the map, we used this tool;
http://www.boekje-pienter.nl/images/kaarthoekmeter.jpg

Im curious why this isn't used in Arma2?

streets
Jan 17 2010, 16:17
Maybe because another system is used? If you have mouth full of orange you can't put apple in there. One system that works is enough and efficient :)

That guy
Jan 17 2010, 16:22
because its too hard.


standard 1:50000 scale maps have 4 digit grids, and any more than that is on the human to add in (6 to 8 to 10 ect). wile easy for anyone who has had some training in maps, it is a bit more difficult for others (especially if there were no ingame tutorials)

Its possible that if BIS used a 4 digit grid coordinate then they would have to add in multiple letter coordinate zones (AA zone, AB zone ECT). by having a 6 digit they avoid it and keep it accessibly simpler.

also then people would complain on how the letter coords were not realistic as they did not comply with real world terrain data :p

edit: also, im not to down with figuring out scale on maps, so what scale is there chernarus map? 1:10000? 1:25000? 1:50000?

Serclaes
Jan 17 2010, 16:23
Most (milsim) units/squads you will find operate with 8 digit coordinates. Only that they have to be guessed.
This was very handy because in ArmA 1 the 6 digit grids used to be 200m by 200m which is very big for a landing point or impact grid ;)

But i know NouberNou is working on a compass, it's maybe even the one you've shown. You can see it for a few frames in this vid at 0:05
-> http://www.youtube.com/watch?v=SH4aG4Yroeg&feature=player_embedded#

DMarkwick
Jan 17 2010, 16:36
I think it's a map config entry that sets it. As far as I can remember, you can specify an 8-digit system in the config if you wish.

SiC-Disaster
Jan 17 2010, 18:42
Actually a six digit coördinate is precise up to 10 meters, while an 8 digit coördinate is precise to a meter.
It's not useful for most civilians to use an 8-digit coördinate, since most already struggle with a 6 digit coördinate.
The 8 digit coördinate is used mostly for precision bombing, but for infantry to find a location a 6 digit coördinate is more then adequate.

Bricks
Jan 17 2010, 19:58
Actually a six digit coördinate is precise up to 10 meters, while an 8 digit coördinate is precise to a meter.
It's not useful for most civilians to use an 8-digit coördinate, since most already struggle with a 6 digit coördinate.
The 8 digit coördinate is used mostly for precision bombing, but for infantry to find a location a 6 digit coördinate is more then adequate.

This is completely wrong, as the OP said a 6 figure grid is a 100m x 100m square. 8 figure being a 10m x 10m square (Refrence) (http://en.wikipedia.org/wiki/Grid_reference). Also for "infantry" a 6 figure is not adequate. A 6 figure (100m x 100m) is 10 000 square meters of real estate, because of the inherit inaccuracy it is rarely used unless indicating a very general area. 8 figure, as the OP stated, is generaly standard within militarys with 10 figure becoming more common as it's the standard readout on most GPS.

Pteradon
Jan 17 2010, 21:48
Actually a six digit coördinate is precise up to 10 meters, while an 8 digit coördinate is precise to a meter.
It's not useful for most civilians to use an 8-digit coördinate, since most already struggle with a 6 digit coördinate.
The 8 digit coördinate is used mostly for precision bombing, but for infantry to find a location a 6 digit coördinate is more then adequate.

It will depends on wich scale map its used, i think;)

The digit coördinate is not only for precision bombing, but also for artillery.
I have use it irl as an recce, for getting mortar support.

As an recce we had to make contact reports with 8 digit coördinates.
The better the contact report is, and the contact location, the better view the overwatch commanders have of the situation.



I was just curious about it, because most of Arma2 players like to play at an high level of realism

Firehead
Jan 18 2010, 09:31
This is completely wrong, as the OP said a 6 figure grid is a 100m x 100m square. 8 figure being a 10m x 10m square (Refrence) (http://en.wikipedia.org/wiki/Grid_reference). Also for "infantry" a 6 figure is not adequate. A 6 figure (100m x 100m) is 10 000 square meters of real estate, because of the inherit inaccuracy it is rarely used unless indicating a very general area. 8 figure, as the OP stated, is generaly standard within militarys with 10 figure becoming more common as it's the standard readout on most GPS.

You're all sorts of jacked up. If you are using MGRS with the typical 1:50000 scale, 6 digits is within 100 meters, 8 digits within 10, and 10 digits within 1 meter. I think you are trying to multiply those numbers (IE 100 times 100 equals 10,000). When instead you should be seeing it as its 100 meters long, and 100 meters wide, giving you a 100 meter radius around where you want to be.

Rattus
Jan 18 2010, 09:56
You're all sorts of jacked up. If you are using MGRS with the typical 1:50000 scale, 6 digits is within 100 meters, 8 digits within 10, and 10 digits within 1 meter. I think you are trying to multiply those numbers (IE 100 times 100 equals 10,000). When instead you should be seeing it as its 100 meters long, and 100 meters wide, giving you a 100 meter radius around where you want to be.

Nope, you're wrong. A square with a side length of 100 meters is in fact 10,000 m² big. Might not look like a huge area on a flat field, but as soon as it's in an urban area, it's too large to be of any real use.

blakeace
Jan 18 2010, 11:46
For most purposes in Arma 6 figures are more than enough. Though it all depends on what you are trying to designate with the reference.
In our group, even when we are calling in artillery fire missions, we generally still use 6 figure, because we like to adjust fire, with the accuracy of the maps, generally using more detailed coordinates just eliminates that part of the fun. That said, trying to describe a non descript building to someone who you want to lase the building for you, there could be half a village within a 6 figure reference.
We may even only use 4 figures if trying to quickly describe where on the map we looking.
"Sorry where did you want to have the landing zone"
"Grid 07 07 Just west of Novy Sobor.

@<hidden>, square metres is different to metres squared. An area that is 100m by 100m is 10,000 square metres, or 100m².

10,000m² describes an area of 10 km by 10 km


A square metre is not the same as a meter square[2], an area 2 metres wide by 5 metres long would be 10 square metres, in contrast 10 metres squared means an area 10 metres by 10 metres. So 10 metres squared = 100 Square meteres.
Above is from the link below.
http://simple.wikipedia.org/wiki/Square_metre

So Pteradon generally for the majority of Arma players anything more than 6 is not really required for how we play and what we emulate in game. That said if you have somebody who creates a J-Dam addon, you would need a minimum 8 figure reference for the pilot to program in otherwise you are just aiming at half a village.:eek::D

Serclaes
Jan 18 2010, 13:15
Are you sure? Because the german page says:

10 m × 10 m = 100 m2 = 1 a (Ar)
100 m × 100 m = 10.000 m2 = 1 ha (Hektar)

And from what i remember from school, this is correct. So 10km x 10 km = 100km².

4 IN 1
Jan 18 2010, 14:07
If I understand correctly, the 8digi system is to divide 10 more grid within the 6 digi system grid right?

Guessing the number should be enought in most case, wouldnt hurt if we could see the grid lines when zoom into a close level through

sprayer_faust
Jan 18 2010, 16:33
An area that is 100m by 100m is 10,000 square metres, or 100m².
I think this is wrong, because "meters squared" is not a standard unit but merely a figure of speech - practical for visualization though: It is easier to visualize 100 meters squared (square, a=100m), than 10 000 m^2.

The unit(label) "m^2" belongs to square meters, therefor:
10 000 m^2 =/= 100 m^2.
I think what you meant was (100m)^2.

I just want to say, that one does not want to assign a unit (with it's own contraction, e.g. m^2) to "meters squared" as it would lose it's initial purpose of visualization and would also mean jibberish mathematically-wise:
100 meters squared + 200 meters squared =/= 300 meters squared.

Firehead
Jan 18 2010, 20:30
Nope, you're wrong.

I've been doing landnav stuff for about 5 years now.

And with that, you're telling me that hundreds of thousands of US Army infantryman have been trained incorrectly, and don't know how to read maps?

In urban environments, 8 digits is the preferred method, because you want to reference specific targets(buildings, street intersections, ect).

A 6 digit grid will get you where you want to go. If you are any decent at landnav, you understand "terrain association", and that makes a 6 digit good enough. Sometimes 6 might be as good as you can get, and you'll have to figure out the rest on the fly.

MulleDK19
Jan 18 2010, 23:54
Actually a six digit coördinate is precise up to 10 meters, while an 8 digit coördinate is precise to a meter.

Really? What game? Certainly not ARMA 2.

It's annoying having to run around for 9322480 years to find a point, because it's so fucking unprecise!

CarlGustaffa
Jan 19 2010, 08:22
http://www.globalsecurity.org/military/library/policy/army/fm/6-30/f630_5.htm#REF30h4

In a grid mission, six-place grids normally are sent. Eight-place grids should be sent for registration points or other points for which greater accuracy is required.

The range shift (how much farther [ADD] or closer [DROP] the target is in relation to the known point, to the nearest 100 meters).


If real world artillery can deal with 6 digit grids, so can we, then interpolate to better accuracies.

@<hidden>:
If you run forever to find a point, maybe it's time to add some descriptions as well? "Yellow house on the right of the road" maybe?

Or divide grid into four sectors/quadrants. If you're still able to get lost within a 50m radius, i.e. 444666NW, then maybe this isn't the game for you :p

Serclaes
Jan 19 2010, 10:02
Of course they can deal with a 6 digit coordinate. But say you want to hit a building/tank/relatively small target a 6 digit coordinate isn't going to cut it. Except if you are willing and able to make the 100x100m look like a piece of Verdun during WWI.

NoRailgunner
Jan 19 2010, 10:23
About Grids: http://www.globalsecurity.org/military/library/policy/army/fm/3-25-26/ch4.htm#fig4-22


There is only one rule to remember when reading or reporting grid coordinates — always read to the RIGHT and then UP. The first half of the reported set of coordinate digits represents the left-to-right (easting) grid label, and the second half represents the label as read from the bottom to top (northing). The grid coordinates may represent the location to the nearest 10-, 100-, or 1,000-meter increment.Additional short and precise target/area informations do help.

Grunks
Jan 19 2010, 13:45
I find that just using the 6 digit grid reference is enough and if more accuracy is needed then divide the grid you are looking at into 9 and visualise that as a keypad. For example 135092 is the reference for the south of Solnichniny on Chernarus. 134091 keypad (or K) 1 means I am talking about the house in the south west of the grid.

Grid ref was slightly off, fixed now.

CarlGustaffa
Jan 19 2010, 22:02
Let me reiterate:

six-place grids normally are sent.

Further interpolating such as sector (NW,NE,SE,SW) or keyboard (K1-K9) can be done with eye with ease. Those gives 50m and 33m grids respectively. If you need better accuracies than those, use an addon that provides an overlay. If 6 digit grid are the "norm" (I'm not saying that finer maps don't exist), I still think 6 digit grid is enough for the common player to play with.