Demeter allows any visitor to modify the terrain around his or her buildings. The interface is very similar to the ActiveWorlds browser's interface for editing terrain. The difference between the AW browser and Demeter is that Demeter uses objects to edit the terrain, while objects are not required when a user has full Caretaker rights.

There are several advantages to using objects for terrain editing in comparison to the browser's terrain interface:

  1. Objects can make use of the world registry in order to prevent terrain from being modified under existing buildings.
  2. Objects allows the terrain under a building to be reproduced exactly when copied by a bot.
  3. Objects make it possible to create a variety of unique landscapes not otherwise possible with the browser's terrain editor. The object properties dialog box has more flexibility than the default terrain editor, such as the ability to quickly modify the terrain over an entire area by pressing Ctrl-Insert. The browser's terrain editor does not allow for multiple cell selection, making this task onerous and requiring much more effort.

Demeter has been programmed to seamlessly integrate with existing worlds. Demeter only concerns itself with terrain under its "marker" objects, and ignores terrain that does not have any markers above it. As a result, Demeter can be started in worlds where terrain has already been built since there will be no terrain markers in a world where Demeter has never before been run. In these worlds, Demeter will not delete any existing terrain unless a new marker is created above or below it by a citizen in the world.

Demeter was conceived for the upcoming Active Worlds version 3.3 in March of 2002 by Brant and with a great deal of assistance from Grimble, an accomplished professional programmer. In conjunction with the release of Active Worlds 4.1, Dr. Squailboont has taken the original Visual Basic code and developed a C++ version, maintaining compatibility with the original version.

A more detailed description is available on the Building with Terrain page.