AIN
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An AIN file is a nodegraph; it can either be automatically generated or made from info_nodes placed by hand in the level. AIN files are used by NPC's to navigate around their enviroment. If there is no existing AIN file specific to that map, or if it was generated for an older version of that map, the AIN file ( <MAP_NAME>.ain ) is generated by the game. The message "Node graph out of date. Rebuilding..." is seen at the beginning of that map if the AIN file was built or re-built.
The graph files are stored in the ..\<game>\maps\graphs directory.
