PDA

View Full Version : 3d crowd scene..help

pekko
07-01-2005, 10:32 PM
i am in a big movie project and i have to find a way to do huge crowd scene.

We have to render some crowd of 10 000 soldiers for couple of shots. Crowd have be made in 3d. 3dsmax is our main tool. We have no money for massive type of system. I was thinking to make my own crowd simulations in 3dsmax script language or with C++ in some standalone soft.

The movement of the crowd is quite simple = just marching, but i don't think that i can do it in max default crowd solver. I have to have solution that don't simulate each soldier at a time but all of them simultaneously.

Another problem will the fact that max is quite incapable to put trough large amount of polygons. So we propably have to render the crowd in sections. But the simulation, of course, should be done for the whole crowd once.

I was thinkin quite simple system that every member of the crow looks the front soldiers and try to keep the distance to them by changing different animation cycles. Animations are probably mocap files.

There seem to be very little to be found of this subject. Have you any idea of the possible implementations i could make? I don't need code necessarily just ideas how this should be done. Thanks.
JHaywood
07-02-2005, 04:30 PM
There's already a basic crowd simulator built into Max 6+, and it's called Particle Flow. :)

I've done this exact thing using pFlow and animated meshes using Point Cache 2. There's a great tutorial on the subject here:
http://www.christopher-thomas.net/pages/free_tutorials/tut_particle_flow_spiders/ct_tut_particle_flow_spiders.htm

To make the soldiers follow along the terrain, if it's not flat, you can use either the Speed by Surface operator, which is okay but not too accurate at times, or a custom script operator. Check out the discussion of this topic here:
http://www.orbaz.com/forum/viewtopic.php?t=228

It sounds like you're already comfortable with programming, so the scripting required should be fairly straight forward for you. If you haven't use pFlow before and run into any trouble spots, just post the questions here for everyone to see.
tuomasj
07-02-2005, 06:38 PM
Here is few crowd simulations test, using particle flow and animated instances, just like JHaywood explained. => www.unelite.com/tuomas (http://www.unelite.com/tuomas)

You can do marching with pflow without any scripting. If you need any help in finnish, let me know :)

--tuomas
pekko
07-04-2005, 01:46 PM
thanks for replys.

i am aware of particle flow :) and already make some crowd tests and that is definetly one solution. But same time i want more control and realism. I don't think i can do without coding or at least scripting.
Not every soldier is suppose to march in same speed. They are not in the same rythm. So each particle must follow the particles in front and if they stop this particle soldier stop also or at least slow down.

Suppose i have couple of character studio characters that use the motion flow, so i can have transitions for one animation to another (i havent done this myself yet, so i am just speculating). Perhaps these animations could be called states. 0-50 walk cycle state.51-80 stop cycle state. and so on.

One of the many problems is that if i use walk cycles how do i easily calculate the speed for the particle? So the legs won't be sliding. If i dont use cycles the distance between particle and mesh grows and makes the distance measuring more difficult between two soldiers. of course i can use trial and error but....

In the end i want have a system that is easy to expand and quite flexible.
CGTalk Moderation
07-04-2005, 01:46 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.