AW CELL SEQUENCE

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Minimum requirements
Added in version 2.1
SDKbuild 13


AW_CELL_SEQUENCE

Type

Integer (read only)

Description

Sequence number of the cell being updated.

Notes

A cell's sequence number indicates when it was last changed. SDK applications and world servers use cell cell sequence numbers in order to stay synchronized with each other about the current state of property in the world.

The sequence number of a cell that is updated (add, change or delete) is set to the largest cell sequence number in its sector plus one. Thus, cells within a sector are ordered by when they were last changed.

If an SDK application is querying property then it must use this number to update the sequence array before another call to aw_query or aw_query_5x5 or it will return the same cells repeatedly (unless the whole sector is empty or could be returned by a single call). The sequence array should contain the sequence number of the cell that was last returned for each sector. And is used as the starting point for the next call.

If an SDK application is in live-update mode for an area and subscribes to AW_EVENT_OBJECT_ADD and AW_EVENT_OBJECT_DELETE then it can update the sequence numbers of changed cells (the sector they belong to) in the sequence array. If both the property and sequence numbers are stored and updated by an SDK application then it will be able to quickly re-query an area after disconnection (if stored in memory) or restarting (if stored on disk).

For a complete description of examining and manipulating property, see Property.

Usage

See Sample Program #2 for an example of how to use AW_CELL_SEQUENCE.

Used by

See also