The two parts of the system interface model:

Operation:     start_mod
Description:    loads the Permutation City mod and sets options
-------------------------------------------------
Reads:          feature list
Changes:        feature list
Sends:          user:{choose_features}
Assumes:
Result:         Q3A is initialized with Permutation City additions;
                the user has specified which features to include
                in the virtual world

Operation:     enter_city
Description:    builds and populates the virtual world,
                then gives the user access
-------------------------------------------------
Reads:          feature list
Changes:        new avatar
                new map, new areas, new items
Sends:          realkit:{play_stream}
Assumes:
Result:         the user's avatar is in the virtual world;
                the media is streaming

Operation:     play_stream
Description:    adds streaming media to the virtual world
-------------------------------------------------
Reads:          feature list
Changes:        new player
Sends:
Assumes:
Result:         the streaming media is buffering

Operation:     new_feature
Description:    helps the user create a new Avatar, Map, or Item
-------------------------------------------------
Reads:
Changes:        new type_of {avatar, map, area, or item}
                feature list
Sends:          q3city:{add_feature}
Assumes:
Result:         the default feature list is user-customized

life-cycle PermutationCity (Interact | Design)*

   Interact = start_mod.#choose_features.
              enter_city.play_stream.

   Design = new_feature.#add_feature.

* - repetition
# - event

Last modified: 7/22/2000