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robrtt

Simple Ai Crowd Simulation

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Hi

Have a lot of free time now, and i'm thinking about making simple crowd simulation in Houdini.

Something similar to this:

http://web.tiscali.it/maya_tutorial/index.html

Yes, its a big challenge but with Houdini should be easy, am I right? hope so :rolleyes: .

Any ideas where start to look at?

I guess POP network, like in Thinking Particles in 3ds (I'm 3ds ex-user).

Do you have any experiences in this topic?

thanks for any help!

cheers!

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the sims being done on the page you link to should be extremely easy to set up in houdini.. they're not even ai crowd sims... just simple particle systems with offset geo loops instanced to each point.. if you were wanting real crowd work, you would need behavioural controls among other things..

To get you going though, look in to the interact pop, follow pop, attractor pop, creep pop, and other standard particle operators...

hth,

dave

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I'm trying right now to create a similar effect.. and I'm stuck with collision detection... lemme show you.

I created various primitives (box, torus and cone) that lays on th ground...

particles slides on ground and follow a leader... everything's fine, well, trickable but working so far.

now i want such particles to "avoid" the above primitives.. and I'm using, but cant get it working, this way ... scatter on such primitives.. generated particles from scattered points, now i wish that the "flocks" interact with such scattered particles by staying away from 'em (like the Interact POP)... how can I set up a "particles1 -> interact with particles2" thing?

or.. looking forward for any different way for this topic :).

cheers.

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With Houdini8, I sure would be building all my pop networks in DOPs. Gives you cacheing for free plus access to very controllable scene object interactions. It also allows you to build your scene as DOP RBD objects to collide your points against.

Just the cacheing alone makes it worth it.

I would also learn and understand the DOP SOP Solver and to a lesser extent the Script Solver.

The SOP solver gives you SOP geometry feedback through the samping procedure. Gosh this could come in handy.

The Script Solver gives you implicit control over any DOP or POP parameter. Gives you lots of options to trigger, switch and modify any DOP data including the POP sub-data!

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Proximity POP is useful here too. I use that in an entry for the 42-node competetion but you'll have to wait until they publish the hips to check out how it works. Centipedes crawl around a terrain and when they meet their behaviour is modified so that one will climb over the other. It uses the Proximity POP and some custom functions to work out when to climb. Definately some of the stuff I did in there will be relevant to what you are doing here. I added comments to all of the SOPs and POPs to make it easier to see what is going on.

Only the proximity detection in carried out in POPs. The paths that the insects take is calculated in SOPs and CHOPs by modifying curves. The advantage of this approach is that it allows you to do a crowd sim with multi-segmented creatures.

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As I remember, In old Houdini 5.0 (5.5?) examples there was such a scene: Crowd of animated simple characters run avoiding some obstacle...

it's as usual... there is there from years...

Merry Chrismas!

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As I remember, In old Houdini 5.0 (5.5?) examples there was such a scene: Crowd of animated simple characters run avoiding some obstacle...

it's as usual... there is there from years...

Merry Chrismas!

23403[/snapback]

i guess i looked in every folder inside "demo" in the installation path.. but didnt found it.. any idea?

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i guess i looked in every folder inside "demo" in the installation path.. but didnt found it.. any idea?

23404[/snapback]

Actually, I don't remember what I'm talking about :blink: . It was a long long time ago. I have on disk *.avi with rendered scene as described above. I have hip file with beginnig, I have folder with geometry (sequence of geo files) so I suppose there was the tutorial about using POPs in crowd simulation. But I can't find final scene... with particle engine :( I'll look around. Maybe somebody here remember where this is come from? I'm sure I havn't done it...

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