[messages] [Module Design] Re: How Is a Module Extension Created?

mycenae ed at crucible.cc
Fri Mar 18 19:16:33 MST 2011

Creating an extension is very much like creating a module. It just uses
a different editor that displays the base module you want to extend. 

Since it extends the capabilities of an existing module, you can't
remove any functionality from the base module, only add to it. For
example, if there's a map in the main module, it will still be part of
the game if you create an extension. There are also other things that
you can't do in an extension--you can't add new sides to the game in an
extension, for example, or add new traits to pieces in the main module.
But an extension is ideal for adding new maps and new scenarios.

To create an extension for a module, in the module manager, right-click
the module and pick New Extension. The extension editor opens (it will
say Vassal Extension Editor at the top). This interface resembles the
regular Module Editor, and should look familiar from creating modules,
as it sounds like you have already. You'll see almost all the same
controls. However, what will be displayed is components from the main
module, grayed-out because you can't edit or delete them.  However, you
can add things like new maps, new pieces, new charts--click around a
little to see what you can and can't add. You can also copy components
from the main module, and then paste and edit these as you need. This is
a quick way to create similar components from the components in the main

It sounds like what you want to do is have the main module with just the
common units palette, and then create new extensions, each with a new
map window that displays a new map. You can add setups to the extensions
just like you would with a module. Players would be able to pick and
choose what extensions to load for a given game session.

After you've worked up the extension in the extension editor, adding
your components, click Save, and save it as an .vmdx file.  (As ever,
it's a good idea to save your work often.)

You need to activate an extension to use it or test it (because you're
going to want to test it), as described in the User's Guide (right-click
and pick Activate). Once you've activated it, you can also launch the
extension editor it by right clicking and choosing edit.

That should at least get you started with the basic process.

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