AI Visually Interesting

From Valve Developer Community

Visually Interesting hint_types are used to mark a specific location which NPC AI should consider looking or aiming at. NPC AI has only a limited capability for recognising Visually Interesting locations which are not marked by hints.

• Although they can be used with any hint node, Visually Interesting hint_types do not need to be part of the nodegraph and, in order to avoid nodegraph problems, should generally be placed as info_hint entities.

• An NPC will consider aiming at this hint when choosing a new target, provided that:
  • There are no hostiles in the area.
  • The hint is within the NPC's viewcone.
  • The hint is in the NPC's range.
  • The hint is not too close.

• Depending on the call, the hint is found during the NPC’s state. Ability to aim may affect their decision and the node may be locked for five seconds to prevent multiple NPCs staring at it in unison.

• For hint #13, If the NPC cannot aim it will look at the hint instead. For hint #14, the NPC won't even try to aim - it will only look at the hint.

Hint Type Summary Table :

Hint	#	Notes	Codename	Conditions	NPCs affected	Use with
World: Window	2	A window that can be looked through. Most NPCs do not need this.	HINT_WORLD_WINDOW		npc_cscanner, npc_spotlight	info_hint
World: Visually Interesting	13	Used to mark interesting areas that the AI would not recognise on its own. A NPC will consider aiming at this node when they next choose a new target. Depending on the call the hint is found during the NPC’s state and ability to aim may affect their decision and the node may be locked for five seconds to prevent multiple NPCs staring at it in unison. If they cannot aim they will look at the target instead.	HINT_WORLD_VISUALLY_INTERESTING	There are no hostiles in the area The hint is in the NPC's view cone The hint is in the NPC's range The hint is not too close	All	info_hint
World: Visually Interesting (Don't aim at)	14	Same as above, but only the head and eyes are affected.	HINT_WORLD_VISUALLY_INTERESTING_DONT_AIM	There are no hostiles in the area The hint is in the NPC's view cone The hint is in the NPC's range The hint is not too close	All	info_hint
World: Visually Interesting (Stealth mode)	16	To do: notes	To do: codename	To do: conditions	To do: npcs affected	info_hint