Entity

A object defined within the Source Engine as having characteristics which differentiate it from "the world" (world brushes).

There are three main types of entities:

• Brush entities are built from brushes and covers its area of effect. They include things such as triggers, conveyor belts, and rain.
• Point Entities are created at a position point in the grid, and has no area of effect of its own, unless it is given a model.
• Nodes are created like point entities, and will together create a network that will aid the NPCs (See below.) to gain knowledge about their surroundings, making them smarter than their basic programming.

There are several sub-types of point entities:

• Logic entities are invisible entities that affect the game, including AI managers, lights, and choreography.
• Prop entities are non-living objects that uses a model for its appearance and function. They can be static-, dynamic- or physics-based.
• NPCs stands for "Non-Player Characters", and refers to all the bots (living/robotic opponents and allies beside the player(s)). They have predefined behavior AI of their own; visible NPCs have their own models too.

See Also

• Entity Creation
• List of entities
• Internal entity