SOM file

A SOM file is recognized by it's .som filename extension. It is the most iconic of files related to Sword of Moonlight: King's Field Making Tool owing it's initials to Sword of Moonlight itself.

History

SOM originated as a two line text file associated with a Sword of Moonlight project folder. The programs SOM_MAIN and SOM_RUN prompt the user to open the SOM file in order to work with a project. Beyond its obvious utility as a media file. since 2013 software that extends Sword of Moonlight had begun to prescribe additional meaning to the file's text, and a day may yet come when a Sword of Moonlight game may be rolled up into a single compressed SOM file that could be as ubiquitous as MP3s.

Anatomy

When a new Sword of Moonlight project is made by SOM_MAIN a SOM file is created inside the project folder. You can open this file up with any Text editor. The first line of the newly created file will name the folder it was created in. The second line is a single 0:

King's Field
0

In 2013, as part of the SomEx project effort to extend Sword of Moonlight's tools to be able to work out of more than one data folder—not unlike the som_db game testing program—it was concluded that the SOM file should be able to define some environment variables for the project. The following variables were initially decided upon:

Environment Variable	Overview Main article: /list of environment variables
GAME	equivalent to the first line of the classical SOM file.
DISC	equivalent to the second line of the classical SOM file.
CD	changes directories in cases where the SOM file is located outside of its game's folder.
DATA	specifies multiple data folders.
USER	Data is looked for first in USER/data, then CD/data, and only then DATA.
TRIAL	specifies the name of a map file where a new game takes place. Ostensibly for testing purposes.
SCRIPT	specifies either a .mo Gettext file or a folder housing a lang and or font folder.
FONT	specifies a list of font files and or font folders.
Ex.ini	specifies a list of Ex.ini configuration files.

Each variable is written on its own line, including an equal sign, and the text value to be assigned to the variable to the right of the equal sign. All written on a single line, not unlike an INI file:

TRIAL=00

As with an MS-DOS batch file, variables should be able to be substituted inside of other variables by surrounding them by percent signs:

DATA=%USERPROFILE%\data; %DATA%

However, this is where the similarity to MS-DOS batch files end.

Lines beginning with semicolons are ignored:

;This is a comment demonstrating comments

Nonstandard extensions

A SOM file is a text file without a standards committee. Technically if a line is not an environment variable it should be ignored. The first two lines are part of its legacy.

Sets

Sets allows lines beginning with + or - or | include individual profiles (eg. PRF and PRT files) and or sets of profiles:

;include short swords found within the Cemetery
+Cemetery 
|short swords

A | line continues a + or - line. It is equivalent to appending each | line to the end of the + or - line. In other words the example above is equivalent to:

;include short swords found within the Cemetery
+Cemetery short swords

A - line is an exclusion statement. Comment lines can appear above or below | lines without terminating a + or - statement spread over multiple lines.

The words of a + or - statement are found among SET files taken from the data folders. If a single + or - statement appears then only profiles named by SET files can be included in the project.

In place of the name of a set, a single profile can be indicated by it's file name. This name must include a file extension. If a name has a period it is considered to be a profile and not a set. If two profiles have the same name but are different file formats, then a set must be indicated in addition to the profile in order to differentiate the files.

Finally, instead of an empty space, a / may be used to separate sets. Where a space yields an intersection of two sets, a / yields a union:

;include both short and long swords found within the Cemetery
+Cemetery short/long swords

All / separates are considered before empty space separators. Just as 3*3+4*4 is usually interpreted to mean (9)+(16) and not ((9)+4)*4. (Note that the grouping parentheses are for illustration purposes only.)