Think Particles Cloud Generator and Mograph
I am using Cloud Generator 1.3 to create some great looking clouds for a project I am working on currently.
I am having an issue, however...
I have a cloud attached to a null which is moving in a non-linear manner (meaning it is moving all over the screen, not just one direction). I am trying to add delay to the particles so they don't all reach the key positions at the same time but have some individual overlap in their animated motion (hopefully that makes sense). I am not having any luck in figuring this out (I've been able to implement other Mograph effectors like the formula effector and random effector, but delay or time or step do not seem to do anything).
Would anybody have any suggestions or ideas on how I can accomplish this? Anyone done this before?
Thanks so much. I admit I am a bit of a newbie and I appreciate any help anyone can give me.
There are a few ways to get there.
You can use the delay effector and/or the shader effector with a noise set to world space so that as the particles pass through darker areas of the (invisible) 3D noise they slow. Make sure to set the fall off correctly so it encompasses the area you want to be affected.
You can also change the particles emission and individual travel speed either with the velocity settings in TP or with "gravity" wells here and there (attractors with very low values - not enough to truly attract them but enough to make the particles think twice before continuing on).
You could also change the particle size so that it shows and then doesn't show as much when in a cluster of other particles doing the same thing (voxels build up as they group together)
I think you could also do a combo of both. Use a global noise piped into expresso to set traveling speeds of the particles with the get position and set position nodes.
Don't forget you can have multiple emmitters all doing something slightly different and each in a different particle group and then have all the particle groups fed into Mograph to have them show up.
One issue with all this might be the cloud formation. As the voxels get farther apart they tend not to group and show up. And you might get some popping in your cloud puffs as they build up, or worse intersect in a way they weren't intersecting on the previous frame. There could also be depth issues - as a voxel passes through or behind another, it will often pop as its depth is reordered by the render engine.
I think you can get there with TP but FYI this sort of particle control is easier with X Particles.
Thanks for your response Steve!
Though I can't quite tell what is going on under the hood of Cloud Generator, it looks like it creates a cluster of particles just once rather than a constant emmission of particles and then that cluster is kind of considered a group of particles that you can then move as a group (or add certain effectors to - some effectors seem to work, others don't). Not sure if I'm describing that correctly or not. I suppose if someone has used Cloud Generator before, they could explain it better...
I guess what I am trying to do is to break apart that "group" so that the individual particles are treated individually so I can get overlapping action on the particles. As the cloud moves I'd like some variation in the speed that individual particles are moving rather than just a random motion of particles moving apart and coming together.
I fear I'm still not explaining myself...
Because of how the volumetric tracer works, and based on the look you are going for, you might be better with smaller thinner cloud groups and then creep each group along individually, overlapping them for the look.
The Cloud Generator is just a preset for Thinking particles and PyroCluster, but it has been optimized for making static bunches of cloud clusters. I'm not sure if we have it here but I'll take a look and see what kind ways you can get under the hood. There should be an Expresso tag on a null in your object manager that you can open up and see whats going on.
And on that note I just realized, because its preset you could just post the project and I could see whats happening. Once the script is in the project its already run and everything is in place so I could work with it.
I understand what you are saying about creating smaller groupings of clouds and then compositing them together, offsetting each of their timings. Unfortunately, I don't know that that will work in this case as the cloud has to maintain a relatively specific shape. But it is definitely worth thinking about.
Here is a simplified project file that I have been experimenting with. The movement of the cloud is actually going to be tracked to a live action shot (and so will have a ton of keyframes - this experiment only has three...). You can see I was able to add a formula effector which rotates and pulsates the particles individually, I just can't seem to be able to offset their timing as far as position goes.