The Active Worlds SDK uses attributes for communicating data back and forth between the application and the SDK. Attributes are similar to variables in that they store values that can be queried and changed. Many SDK attributes are read only, meaning that they cannot be changed by the application and exist only for communicating information to the application from the SDK.
Attributes are stored per-instance. This means that in a multi-instance application setting an attribute sets it for the current instance only.
Typically, in order to pass data into the SDK, an SDK application sets one or more attributes before calling an SDK method. Once the method completes, the application then queries one or more attributes to retrieve the results of the operation or event.
Attributes can have one of four data types: