ACWCO Engineering Department

ACWCO Engineering Dept.


HPS/JTS OOB's Explained

The .oob file contains the army organizations for the HPS games.

Beginning with Corinth 1.02 the HPS ACW games had the .map files locked out so that only the original files would work within a particular game engine. You could make your own oob file and load it into the Scenario Editor, it would work fine there and you could create a scenario file with it. However when you attempted to start the scenario file in the game engine you would get an error message.
However with the release of the JTS Overland game the .oob files appear to have been opened up again. Currently those games that have been updated to version 2.0 allow oobs other than the originals to be loaded.

Two things to keep in mind if you're going to modify an OOB file.

1. You want to be careful not to modify the existing oob file so it doesn't affect your ability to play the original scenarios from the game.
2. You want to make sure your opponent is aware of the changes you make and agrees to them before starting the game.

The easiest way to modify an oob file is to open it with a text editor, you can use Notepad or WordPad both of which come with most pc's or any other straight text editor provided you remember to look for .txt files when opening the .oob file. Then using the Save As function in the File menu you can use the original file name and add a number or letter to it such as Antietam_1A.oob or give it a name that indicates what game it is for and your initials such as Antietam_KM1.oob. It will already have a .oob extension this way and you should not have any problems with the file. Then when you create a scenario to use the oob file in you can note that it uses a modified oob file in the description.

The army organizations for the HPS ACW games are found in the *.oob files. So far in all games the Union Army is listed first then the Confederate Army.

At the top of the file is the version number. To the best of my knowledge the current version number is 3 in all the games. Then the Order of Battle begins.

The example below is taken from HPS Gettysburg and is a shortened version of the file for demonstrating the make up of the file. I've shown part of the Union 1st Corps and left out the Confederate forces except to show where they would be located and that the first line must indicate it is a Confederate formation.

The first thing you'll notice is the outline format. This helps to identify the hierarchy of the various formations. As you go through the Order of Battle remember that each indentation denotes a subordination to the above line. You will note that each formation (defined as any organization above the unit level, can be comprised of leaders, units and subordinate formations) has the word "Begin" directly under the formation's title line. Any leader, unit or subordinate formation belonging to this Formation will be at the same indention. The Formation continues until you see the word "End" at the same indentation. The "Begin" and "End" can be quite widely seperated but if you have a text editor that shows the space number it is easy to find the "Begin" and "End" of each formation. The most common cause of errors in loading oob files is an extra or missing "Begin" or "End" in the file. Using the proper indents makes it easier to avoid this mistake.

To the best of my knowledge there is no limit to the number of Armies you may list in a .oob file. It was thought that there was no way to place a leader in charge of more than one Army. However according to John Ferry it can be done
"If you want to show armies subordinated to a higher command, such as Grant in Overland, commanding Burnside, Meade, Sigel, and Butler, you can do that by using the "A" identifier without the "Union" prior to the "A" for example



Each of the formation levels must be prefixed by a particular letter as shown below.
A   Army
C  Corps/Wing
D  Division
B  Brigade
You may omit levels if you wish. However, with the missing link in a chain you may jeopordize the Morale bonus that is handed down from senior to junior leaders and eventually the units themselves. The name after the formation letter can be any text, In the Murfreesboro.oob the corps are referred to as wings. The one limitation I have found is that the name should not contain more than 19 characters. This is because the name is displayed centered in the unit display box and it has 19 spaces. If you exceed 19 characters both ends of the name will be cut off making it difficult to read.



In addition to the Formations individual units within the command also have letter prefixes.
L  Leaders
U  Units, these can be Infantry, Cavalry, or Artillery as will be shown later.
S  Supply Wagons
G  Gunboats

Below is a typical leader and an explanation of what each character in the line means.
L 4 5 41 MG G G Meade
4 This is the officer's Leadership Rating, this rating is used in assisting routed units stacked with the officer to rally.
5 This is the officers Command Rating, this rating is used in determining whether or not the officer is "In Command" and can pass along a Command Bonus to his subordinate units.
41 This is the pointer to the leaders.bmp file that indicates where the leaders picture is located in the file. The file is located in the Info folder of the game and consists of a series of pictures that begin with picture 0 in the upper left corner then count left to right on each row. There are 12 pictures located on each row so the first row contains pictures 0-11. The second row starts with picture 12 on the left and rows continue till the end of the file. If a number is used outside the limits of the file no picture will be shown.
MG G G Meade The leaders rank and name. Once again you do not want to exceed 19 characters or the name will not fit in the unit display box as noted above.


Below are typical unit lines and an explanation of what each character in the line means.
U 288 6 I R 96 11 19th Ind
U 42 3 C C 73 0 Oneida (NY) Co
U 2 5 A T 32 10 (A) 2nd, Me Lt
Using the Infantry unit's values.
288 This first number indicates the number of men in the unit if it is Infantry or Cavalry (42) or the number of guns if it is an Artillery unit.
6 This is the Class rating for this unit with 6=A and 1=F
I This indicates the first unit is an Infantry unit, the second one (C) is Cavalry and the third (A) is an Artillery unit. There are several other letters used here. H indicates a Horse Artillery unit giving it a higher movement rate than foot artillery. There are also two other letters used in some oob files for Infantry units, M for Militia units and S for Sharpshooters. To the best of my knowledge these are for informational purposes only and have no affect on the unit's abilities unlike the Napoleonic games where different units have different abilities.
R This is the Weapon that the unit is armed with, in this case the 19th Indiana is armed with a Rifled Musket. There is a file available for download with a list of the various letters used by the game engines and the corresponding weapon on the PDT page of this site.
96 This is the pointer to the units.bmp file that indicates where the unit picture is located in the file. Like the leaders.bmp file this file consists of a series of pictures that begin with picture 0 in the upper left corner. There are 12 pictures located on each row so the first row contains pictures 0-11. The second row starts with picture 12 on the left and the file continues indefinitely.
11 This is the pointer to the 3DUnits100x.bmp file that indicates where the unit 3D icon is located in the file. These files are located in the Maps folder of the games and the number refers to the row used for this unit. Each row consists of 6 pictures except for 3DUnits100c that has 12 pictures, 6 for infantry/cavalry in line and 6 for infantry in column. There are several such files for the different units with 3DUnits100a.bmp being for unlimbered artillery, b is for mounted cavalry, c is for dismounted cavalry and as previously mentioned for infantry in line and column, it also contains the routed unit icon for both sides. 3DUnits100d.bmp is for limbered artillery and wagons, and g is for the various gunboats. Like the leaders.bmp these files have the icons for both sides. There is also a 3DUnits50x.bmp file for the zoom out 3D view.
19th Ind This is the unit name that will appear in the Unit Box display. Once again I caution you about exceeding 19 characters in the unit name or it will not fit in the unit display box as previously noted.

There are two more unit types.
S 300 36 Supply Wagon
This is a Supply Wagon as denoted by the S and the name.
The 300 is the number of supplies this unit starts out with and the 36 is it's unit picture number.
Supply Wagons are sometimes located within a formation. Other times they are placed at the end of the oob in which case they require a Union or Confederate designation in front of them. There is no difference between a Supply Wagon that is placed within a formation and one located at the bottom of the file other than the fact that the one in the formation will be highlighted when the Show Organization option is turned on. Both types will provide resupply to any units located within the supply range.

Union G 4 6 p 80 00 Louisville Gunboat
This is a gunboat unit, denoted by the G.
The remaining values are the same as those of any other unit with 4 being the number of guns, 6 being the unit class, p the weapon type, 80 the unit picture and 00 the 3D icon.
I have not seen gunboats placed within any formation, they are normally placed at the bottom of the .oob file with the appropriate Union or Confederate prefix as shown above.

That about covers everything you need to know about oob files except that you will probably have a problem loading your first one as most of us make a mistake somewhere along the line. If when you attempt to load the oob into the editor and you get an error message I suggest you look at the Unit Dialog box. This is often useful when trying to find the error. If you find the Union command is loaded but not the Confederate this will indicate the problem is somewhere in the Confederate portion of the file. You can also try saving parts of the oob file and attempting to use that in the editor to narrow down the location of the problem. These tactics are especially useful when dealing with a large oob file.


The last thing I want to cover is the easy way to change the oob file for a scenario. This can be done without having to redo the scenario from scratch provided you have only changed the data in the lines of the oob. If you left the organization intact and have changed only unit strengths, class, weapons, picture and icon id's or names you can use this procedure. If you have added or deleted lines in the oob file you cannot use this procedure because of the way the scenario file is saved.
To do this you open the scn file with a text editor, once again the first thing you want to do is rename the file in the same manner as was described above. To do this you use the Save As function under the File menu. After that you should have something like this displayed in your text editor.

Battle of 1st Bull Run (Manassas), July 21st, 1861
1861 7 21 3 0 0 0 1 38
10 20 30 2
10 20 30 2
-1000 -500 500 1000
4 4 0 0 4292 0 0
600 500
1st Bull Run.oob
0 0 0 0 0 0 0 0 0 0
2 2 2 2

If you change the name of the oob file in the tenth line you can then save the file, when opened it will use the new oob file you specified. Next you'll want to open it with the Scenario Editor and make a note in the Description explaining that the new scenario uses a modified pdt file and maybe noting what was modified in the oob file.

WARNING - if you change the organization of the oob file in any way, adding or deleting a unit or line you cannot use this method because of the way the scenario file saves the unit positions. If you try you will get an error and the scenario will not load properly or if it does load the units will be scrambled.


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Page designed and maintained by Ken Miller
Last updated 10/08/2015

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