COIT23003 Games Development 6. Elaboration: Entities

References Meigs, T., Ultimate Game Design: Building Game Worlds, McGraw Hill. Adams, E. and Rollings, R., Fundamentals of Game Design, Prentice Hall.

Entities Game entities include – Actors – Props – Cameras

Actors An actor is an entity that exhibits behaviour. The following types of actor commonly appear in games: – Protagonists – Adversaries – Non player characters (NPCs)

Actors: Protagonists Controlled by the player; usually is the most sophisticated actor in terms of behaviour, animation etc. -e.g. Mario

Actors: Adversaries Not restricted to “human” Should provide challenging behaviour, but not too challenging Often used to “protect” resources – need to balance the risk/reward value

Actors: NPCs Are used for – Narration – Advice – Instruction

Actors: Design Issues Type Quantity Behaviour Placement

Props A prop is an item used by an actor to further the plot or storyline of a game. Props can be – Static (collectibles, ammunition, furniture, …) – Damageable (has states, eg wall -> wall collapsing -> rubble) – Scripted (as for damageable, but involves additional entity behaviour, eg release of creatures)

Props: Design Issues Type Quantity Placement Useage (create realism, destroy and reveal, landmarks … ) (Meigs, p.93)

Cameras Cameras are critical in achieving the desired perspective in 3D games

Cameras: Perspectives Common perspectives are First person (camera = your character’s eyes) Third person (camera follows your character at a fixed distance) Aerial (camera views a large part of the game world from directly above) Isometric (as for aerial, but from an angle) Floating(as for isometric, but user can position the camera Context sensitive (camera follows the action and positions itself in the best position)

Cameras: Design Issues Choice of perspective (tradeoffs include platforms, gaming requirements, programming effort …) Flow (avoid abrupt camera changes) Provide default positions for floating cameras