particlesAlongPath.toe (8.08 KB)
I’ve been struggling to wrap my brain around using the attributes within point and copy sop to control particles. What im trying to do is have the particles inherit the shape of the profile curve as they move along it, so basically flow with the profile curve… I’ve been able to get things rigged up to chop index values but nothing that follows the shape like a path…just totally lost on how to approach it, any ideas to get me started? would be much appreciated!
particlesAlongPath.toe (8.08 KB)
particlesAlongPath.toe (8.08 KB)
Particles flow along the vector of a normal. If you orient your normals along your path, this should help you get started.
Here’s a sample file to help see what that looks like.
The first set of particles does not have a set of normals.
Second set has +1 added to the y normal parameter in the point SOP.
Third set has +1 added to the z normal parameter in the point SOP.
Fourth set has time sliced noise added to the y normal parameter in the point SOP.
Fifth set uses a noise chop with the same number of samples as the source geometry to assign a sudo random number to each point on the line.
The camera is set to revolve around the center of the scene to help make it easier to see what’s happening.
particleEmit.1.toe (5.56 KB)
Sorry, one last note. All of the red colored null SOPs should be set to display normals so you can see the direction of the particle’s vector.
I also looked at your source file.
First off, if possible, I’d avoid using something like the copy SOP. That might perform well initially, but is likely going to become a bottle neck at some point - all of those SOP transformations are happening on the CPU, and it’ll just make trouble for you. The copy SOP is excellent for pre-transformation changes, but for moving geometry I’d avoid it - at least, that’s my two cents here.
Instead, I think you’d want to instance your geometry using your particles as points. The same idea as the copy SOP, but it means you can take better advantage of your GPU. This also allows you to take advantage of a point’s given life time and apply that to the alpha of the instance - points will fade away rather than popping out of existence.
I’ve also added a set of buttons so you can toggle through the various ways you might apply your noise and curve to your particle system - changing the point position for xyz, or assigning a normal for xyz. In this case, you don’t need a point SOP because you’re using the CHOPto in order to assign the normal / position information.
particlesAlongPath.1.toe (9.44 KB)
Awesome, thanks again Mathew. I was going about it wrong, went a different route and got something pretty close to what I imagined. I emit from a sphere along a path, and keep the petals in a bunch together using force+metaball sops - kinda looks like wind keeping them bunched together. Together with crop top I can make sprite sheets as well cool stuff!
NewProject.toe (11.7 KB)
