Particle Clouds controlling Particles - That 'Organic' Look?

[thomashogben]

Hi Everyone,

I have been working on building some particle effects within Softimage and the ICE system that instead of using a complex web of node commands, are built out of 2 or 3 simple control clouds which control the main simulation. These control clouds are then hidden when the final render is created, and each are built to achieve a specific role, like control direction, turbulence and scale. The main cloud then runs off a series of neighboring particle controllers that relate to the control clouds.

I have found this quite a effective way to control elements that require that 'Organic' look, like flocks of birds or leaves as well as for a project looking at the path Light takes through space (if visible, as if 'filmed' at a trillion frames per second). It seems to create a look that is less contrived as that achieved with turbulising nodes and cut of distances with in a single ICE tree, which is how I had previously developed this type of simulation.

Is this something that others often use? or does anyone have any opinions on this type of technique?

[Tekano]

Hi Thomashogben

sounds interesting, I can understand a frustration with turbulence only as it often leads to particles gathering 'in the gutters' and converging in the same place all the time. I do believe that is what the curl noise framework is meant to address, have you tried this out?

also, without seeing any demonstrations it is hard to appreciate what the difference is between one Ice tree being driven by many simpler trees or just one main Ice tree. Sometimes it is easier and less computationally expensive to cache out data into clouds and use these datas to further an effect and often when trees are getting complicated then it is really simple to just make a compound. performance wise I can't imagine there being any benefit to doing it your way over the more traditional one large ICE tree, but conceptionally perhaps its better - but who knows!? show us some stuff to see

[druitre]

Hi Thomas, sounds interesting. I'd like to see examples too!

[Matic]

From your description I'm not sure how you are getting any behavior which is really different from what you can get within a single operator, using linear interpolations.

If I understand you, you are creating several simulations and then effectively blending them, correct? As a general rule this kind of thing can be very powerful. For instance, in practice it's often very useful to simulate and cache out a number of versions of a simulation and then blend between them over time to obtain the best results of each. This works particularly well in cases where two very different kinds of motion must be brought together, as comes up with some regularity in hair and cloth sims, or for cases where a certain keyframe must be hit exactly, where you can blend a simulated element with a shape animated one, for example.

So I suspect your core concept is a good one that is reflecting a proven and valuable kind of workflow... but AFAIK you're the only person doing it in this particular way. Would love to see an example.

[etmthree]

Yes, please -- examples! Sounds cool, especially if you can make it look like flocking starlings!

[angelous4x]

This sounds like a very interesting (Samurai style) technique, ;)

Looking forward to like a type of tut.

[Helli]

Hey there

For me there isn't much difference between having 1 big tree or several smallers. Thats why we got compoudns for no ? To group seperal tasks and make the tree clean.

[angelous4x]

I could see a good use for it, we are working on a project what an artist used something similar. one particle does one kind of fluid animation, and a clump of particles flowing it as an soft constant force. and the clump of particle has a another kinda of fluid animation. using that as a point force. it was an easy way for him to control one cloud at a time. didn't see the ice tree but thats how it was explained to me.

[Helli]

I could see a good use for it, we are working on a project what an artist used something similar. one particle does one kind of fluid animation, and a clump of particles flowing it as an soft constant force. and the clump of particle has a another kinda of fluid animation. using that as a point force. it was an easy way for him to control one cloud at a time. didn't see the ice tree but thats how it was explained to me.

I used that for fluid sims as well. Cheap way to have a certain behavior without having to actually compute special forces on all particles.