ACWCO Engineering Department

Creating HPS/JTS ACW Game Maps with East Front

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 MAP 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 game Overland the .map files appear to have been opened up again. Currently those HPS/JTS games that have been updated to version 2.0 or later allow maps other than the originals to be loaded.

Creating HPS ACW Game Maps with
Talonsoft's East Front Map Editor

First you should be aware of the fact that because it was designed for a tactical game the East Front Map Editor has some limitations that will affect your map making, the biggest one being the maximum number of elevation levels it supports is 13 while some of the newer HPS engines currently use maps with over 20 elevation levels.

In order to create your own maps you will need.

1. A copy of Talonsoft's East Front Game which includes a map editor.
2. A text editor with a Replace function for modifying the map file text to convert it from East Front to HPS ACW format.
3. A Checksum calculator program, two are available for download on this site.

Before going any further I wanted to mention that these instructions are for the original East Front Map Editor. I managed to get hold of a copy of East Front II and looked it over but it appears some type of encrytion was put in this second version. This causes the characters in the map file to vary from one map to another making it difficult if not impossible to use this version of the Map Editor for creating ACW maps.

Since there are some differences in the format of East Front and HPS ACW maps you need to follow some guidelines when using the East Front Map Editor. Below you will find a table listing the comparable terrain used by both games, as you can see although many of the letters are the same there are a few differences in the letters used for the base terrain and the position of the blocks for some of the hexside terrain features. Also East Front has additional terrain features that have no comparable HPS ACW feature and these have been left out of this table. A more complete Excel version of this table is available for download on this page.

EF Terrain	Letter	HPS Terrain	Letter
Clear	space	Clear	space
Water	w	Water	w
Forest	f	Forest	f
Swamp	s	Marsh	s
Village	v	Town	t
Orchard	o	Orchard	o
Rough	r	Rough	r
Field	e	Field	d
Blocked	x	Blocked	x

EF Hexsides	Block	HPS Hexside	Block
Path	17	Trail	3
Unpaved Road	14	Road	4
Paved Road	3	Pike	5
Railroad	4	Railroad	6
Stream	5	Stream	7
River	6	Creek/River	8
Hedge	10	Fence	9
Cliff	12	Stone Wall	10
Embankment	13	Embankment	11
Gully	15	RR Cut	12

I recommended using the designated East Front terrain for a particular ACW terrain type. This is not the only way to do this but it is the way I have used, I think it is the easiest way and it works. A step by step procedure follows. I recommend you start with a small test map and do this a couple times to get the hang of it before attempting anything large.

Using the tables above create your map using the recommended East Front terrain types. Due to differences in the way the two games handle the map files you will need to make several changes to the .map file using your text editor. I suggest after completing your map you copy and save your map under a new name, say you called it main.map, then use main2.map as the new name. This will allow you to have the original East Front map and your modified HPS map. This will make it easier to affect the changes needed and keeps your original safe in case you mess up the modifications.
 
In addition to the differences in the letters used for some terrain features the map files for the two games are built a little differently. As noted in the Map Files Explained section of this site the HPS ACW maps are divided into a Header section, a Terrain block, an Elevation block, 10 Hexside Terrain blocks and a Labels block. East Front also has a Header section, a Terrain block, an Elevation block, but it has 15 Hexside Terrain blocks, an additional block who's function I do not know and a Labels block. Several of these blocks are not needed for the HPS ACW games and in fact will cause problems if you attempt to load an East Front map into a HPS engine.
 
The first change you need to make will be to replace the East Front Village letter v with a t. This can be easily done using the Replace function. You want to use the Replace Next function not the Replace All as this may mess up any Label names you have put in the map. You only want to replace the v's in the first block of the map file as described above.
 
Next you want to do the same thing replacing the East Front e for Fields with the HPS d.
 
The elevation blocks are the same in both maps, a series of numbers from 0-9 then letters from a-c desginating the elevation level of each hex from 0-12, so you do not need to make any changes in the second block.
 
The next set of blocks contain the biggest differences between the two types of maps. As noted above the HPS ACW game maps have 10 Hexside Terrain blocks while the East Front map has 15. If you used the suggested East Front Hexside Terrain features you will have 5 unused East Front blocks that will consist only of a 0, an indication that block is not used. However you will still need to move the East Front blocks into the correct positions in order to get them to work properly in the ACW engine.
 
A good way to do this would be to start at Block 3, in the line below the end of the Elevation Block. There you'll see a line containing either a 0 or a 1 depending on whether or not you had any Paved Roads (ACW Trail) hexsides in your map. If a 1 it indicates the start of block 3, if a 0 it would indicate there were no Paved Roads used in your map. I suggest you replace the 1 with a 3 then scroll down through the file replacing the 1 or 0 at the start of each block with the next number in the sequence. When done you should have 15 lines containing a single number from 3-17 with a series of blocks of various characters between them.
 
Blocks 7-8-9-11-16 should consist of single lines since if you followed the instructions you should not have used these blocks so you can highlight those lines and delete them.
 
Just below the end of block 17 you should see a 1 followed by something similar to the Terrain and Elevation blocks. I'm not sure what the function of this Block 18 is but it is not needed for the HPS ACW engine and can also be deleted. You are now ready to move the blocks into the correct order.
 
If you look again at the table above you'll see the correct order to place the East Front blocks in order for them to match the blocks in the HPS ACW engine. You'll note that several of the blocks, 3 through 13 will not need to be moved if you move the others into the correct positions and delete the unused blocks as noted above.
 
Now you want to highlight block 14, using the Cut feature, cut it out then paste it in front of the 3 designating block 3. Then do the same thing with block 17 pasting it in front of block 14. If you have already deleted blocks 7-8-9-11-16-18 then you should now have a map file consisting of a Header section, a Terrain block, an Elevation block, 10 Hexside Terrain blocks in order 14-17-3-4-5-6-10-12-13-15 and a Labels block.
 
The only thing remaining to be done is to replace the numbers you put in earlier with a 1 if that block was used and a 0 if it wasn't. After doing that you can save your map file and you are ready to determine the Checksum for the file.

Leib Checksum Generator Program