How does quake and unreal and every other FPS do the Ai for the npc''s. I imagine they use some sort of bounding sphere, or box, etc and then if it colides, it turns, until it can move. but has to be a smoother, better approach. well thanks for any input Code makes the man

I remember the old game Doom - if you opened up the map and activated the display of the objects as triangles, they were constantly bumping into the walls, then going in a random direction away from the wall to attempt another approach.

That worked well for the simplicity of Doom and the volume of creatures handled, but as the games evolved, the gamers demanded more realistic gameplay...

I don't think the simple move-til-you-hit-a-wall method works well anymore. Most games nowadays, I think, will pre-determine a path for the object to take, and the object takes that path intelligently, re-evaluating its path occasionally as it goes.

To assist with this, maps may contain waypoints at junctions as part of their data that AI creatures and objects can use to help guide themselves. It would be possible to programmatically calculated all those waypoints at the proper junctions, but they would need to be stored in memory for re-use. Recalculating them for every move request would be far too time consuming.

Exactly how the AI movement is handled in the latest games, I can't say... there are algorithms out there, though. The book Game Programming Gems provides some insight.

- Waverider

Edited by - Waverider on March 3, 2002 8:04:50 PM

Games today normally uses waypoints to for bot navigation. It is basically a framework of interconnected nodes that a bot runs around between choosing paths depending on what it desires to do. As Waverider said, it is important to keep down the number of CPU cycles used for the AI in games, and therefore predefined paths is pretty much the only way to go at the moment.

EyeonAI.net - focusing on Artificial Intelligence

Hi!
An idea for multiplayer-bots.
I think it would be interesting if they are some waypoints
at the beginning but that the AI can copy the waypoints of your soldier. I mean the programm should insert some new waypoints copied from the playing players who probably score.
And surely deletes Waypoints who the player don''t use.
I think it would be an interesting idea to implement.

Hope you understand what I mean: C.Ruiz

Load up Quake 3 arena in q3dm1, on the easiest difficulty (so the bot player ignores you) And you''ll get a good idea of what they''re doing. You can follow the bot around and watch him run laps around the level, same path every time. Increasing difficulty from there just adds more willingness to deviate from the path to take shots at the other players.