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Next.. Ambient NPC population

Marleys Ghost

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Working on two principles K.I.S.S. (keep it simple stupid!) and more for less.

 

I spent a lot of time researching (read playing) certain games that have what I call an ambient NPC population. This is specifically those NPC's that reside in the background and generally have no real or very limited interaction with the player. Two such areas of research <coff> included Assassins Creed and Fable 2. Although both of these games have a far more complex general NPC population than what I am setting out to create, but the "research" was most enjoyable.

 

First Step:

 

Machine Intelligence "Kinda Almost":

 

Machine Intelligence "Kinda Almost", simply gives an illusion that there is intelligence at work but there is not, sort of like, the lights are on but no ones home. There are several subsets to this group but the obvious one is simple animation. Also this can include proximity reaction behaviour, a posh and complicated way of saying when the player is near, stop what you are doing, and do this instead. But that's as far as interaction goes for those NPC's in this group. This simple ambient NPC type could also use lua scripts, loaded with the level and be left to attend to themselves.

 

For example, just two chaps having a chat:

 

blogentry-12-053597000 1283986535_thumb.jpg

 

Having a chat is basically all they do, its simple per character animation's controlled by lua scripts. The purple block volume is the walkable area that would be utilised by more "advanced" ambient NPC's, typically those that move about, particularly those that would use Pre-Loaded and Pre Calculated path routes for this particular level. The purple block volumes are simply required by the application I wrote to generate the route node data for the pathfinding tools I created and have demonstrated here. Not that this is a level just something thrown together for testing but I think I should unarchive some of my GMF format models and put together a small town/Village for testing this, rather than another simple "BlocksVille".

 

There are obvious limitations to consider with this approach to the first tier of the Ambient NPC population for a "busy" town/village. The NPC's need animation's, most come with maybe 15 animation's (if you're lucky). My intention is to surmount this by adding animation's to them, primarily Mo-Caps. This will require a little work but will be the bedrock for the construction of this "tier". There are some very good applications on the market for achieving this. For me I prefer Fragmotion, there is also a free alternative that I also use on occasion called Pacemaker. But don't be fooled though, none of these applications will do it all "for you", you will need to skin the mesh to the correct rig for the plethora of free to use Mo-Caps, or indeed ones that can be purchased. It will all depend on budget and or requirement.

 

This is still only a very basic outline for this "packing" stage, it will still require a lot of work but my goal is to get the impact of it at runtime to an almost negligible effect even when including proximity reaction behaviour.



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That's a really interesting read MG. A subject that I've only just considered, ambient mobs or mobiles. Reading what you wrote sparked a few ideas on zones and assigning such spawned entities to different movement behaviours within them.

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Guest Red Ocktober

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yes... this is something that has, for the most part, been totally ignored by many, yet something that a lot of games will need...

 

good stuff MG... keep it coming...

 

 

--Mike

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I wouldn't go so far as to say ignored. Getting to the point where you need these kinds of objects is a pretty big step.

 

My ideal way of working with NPCs would be to drag some form of "Crowd" box into the editor and adding characters, specify number, variation, movement pattern in the box. Not just people but animals too. Chicken runs, birds, cows. That would be a pretty high-level operation, but wouldn't it be a fantastic way of populating such scenes?

 

That would be awesome. Even those people that use Leadwerks for architectural visualisation, putting people in the scene that move about would be pretty handy.

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Guest Red Ocktober

Posted

I wouldn't go so far as to say ignored.
i actually would... the reason being is that this is the first thread that i've seen here that even looked at the aspect of adding this sorta realism to a scene from this perspective...

 

i mean, i easily might've missed one... so, if you could point me to it, i'd be interested in seeing what approach was proposed there, but most of the game dev i've seen here so far, that involve characters, centers mainly on the players character, and the antagonist(s) or bad guy(s) character... nowhere have i've even seen mentioned the idea of having incidental characters that appear (or that actualy are interactive) as an added element of realism for a scene...

 

Getting to the point where you need these kinds of objects is a pretty big step.
i might not agree with this assertion either... depending on the type game you're crafting, incidental npcs might start appearing at any point past the initial development cycle... just as you'd consider adding lighting, structures, or any other scenery elements that contribute to the ambience of the surroundings...

 

 

 

--Mike

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Good stuff, MG. I can't wait to check out a video with the progress. Screen-shots for AI doesn't do any justice for it.

 

 

Sorry Paul would have got back to you sooner but as you know I am "spring cleaning" the Dev system lol

 

 

Yes a video is always preferable with AI but this is still in its early stages and so far all there would be is the two NPCs running through thier respective animations. But I will certainly use videos in the later dev stages. :D

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That's a really interesting read MG. A subject that I've only just considered, ambient mobs or mobiles. Reading what you wrote sparked a few ideas on zones and assigning such spawned entities to different movement behaviours within them.

 

 

Thanks Flex, I always hope some (or any) of my musings help others, I feel this to be an important part to game dev. thus worthy of thinking about. A lot of the ambient life I see in games simply is "smoke and mirrors" .. had the Great Bard been an Indie developer I think he'd have said "All the game world's a stage, And all the NPC men and women merely players. They have their exits and their entrances..." And typically thats what the tier idea is about .. not every NPC will require complex or even medium AI coded ability nor even A* .. I am simply trying to work as though its a film set ... Extras .. walk on parts .. co-stars and stars ... that sort of thing. Still needs better formulation though.

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