Engine: data structures (3.2.1)

AGS Engine defines a number of structures for storing game data. They may be roughly divided into static and runtime ones depending on their behavior during game run. Static data is saved by the editor when game is compiled and loaded when game is run by the engine; it may be partially written with the saved game. Runtime data is initialized at game start, written when game saves and read when game is being restored.

General game data

• Static type: GameSetupStruct, inherits GameSetupStructBase;
• Static object: GameSetupStruct game.

GameSetupStruct is partially written to the saved game;

• Runtime type: GameState;
• Runtime object: GameState play.

Additionally, current game configuration is being stored as:

• Type: GameSetup;
• Object: GameSetup usetup.

It normally does not change hence may be considered static data.

Room data

• Static type: roomstruct;
• Static object: roomstruct thisroom.

thisroom stores information of current room only (the room player character is in), other rooms are not stored in memory all the time, but being read to thisroom as new room loads.

• Runtime type: RoomStatus;
• Runtime objects: RoomStatus *roomstats, RoomStatus troom, RoomStatus *croom.

roomstats array stores MAX_ROOMS runtime room states; troom is a temporary room data used for non-state-saving rooms (those with number beyond MAX_ROOMS); croom is simply a pointer to current room's state: either one of roomstats elements or troom object.

Character data

• Static/runtime type: CharacterInfo;
• Static/runtime object: CharacterInfo *chars defined in GameSetupStructBase;
• Runtime type: CharacterExtras;
• Runtime objects: CharacterExtras *charextra, CharacterInfo *playerchar, CharacterInfo *facetalkchar.

CharacterInfo objects are being changed during game run. Array of CharacterExtras provides extended data that cannot be put into CharacterInfo struct due backward-compatibility considerations. playerchar is a pointer to player character's CharacterInfo element from chars array. facetalkchar is a pointer to the character that is being speaking in Sierra-style dialogs with close-up portraits.