[Was Keyed Particles] Harmonics, struggling with the timing: any hints?

I’m trying to set up a scene in the following way. I’ve a keyed particles system and want to morph the particles over multiple meshes. Currently the particles are fine moving among the meshes but I cannot set up the timing in the right way. I want to stop the particles on each meshes for a specific duration and move them from one mesh to the other one accordingly to my needs. But so far it seems that the timing field only works accordingly to the main particle life value and that’s a shame, no chance to get more from this…

Any idea?

Are you using the harmonic effector?

Forgot to mention, I’m using 2.5 and I’m following this tutorial:

Quickly trying the harmonics, never used that before though… just giving it a quick try.
First problem it seems the Surface Type is not working well. Second problem: to keep the particle on the first mesh and move them on the second mesh at a certain time, I’m animating the Maximun range of the Sphere Falloff. It seems to work, but when the falloff it’s 0 again to stop to attract the particles, they simply go through the mesh… it seems harder with the harmonics, keyed seemed to be a good solution it’s a shame for the timing issue though.

Feel free to check out my Emulating The Cherry 7-Up commercial tutorial here:

It shows how to use the harmonic effector to cause a group of particles to travel from one mesh to another and roughly take on the shape of that mesh. In this example, both meshes are words. The timing control is explained in the video.

Thank you Atom. Trying your steps right now but I guess the parameters behave in a different way in 2.5…

Here’s a test file:

As you can see I’ve three object, right now the third object (TYP_E) is on the second layer. It seems the transition from TYPE to Susanne is working, as soon as you move the TYP_E object from the second layer to the first layer, it gets messy.

You have the harmonic effector setup wrong.

Try this…

Harmonic effectors only work with the particle system that are on the same layer as the target meshes. So put all your meshes and particle systems on the same layer.

Then select the Monkey and then the physics TAB. Set the Fore Field to NONE. You don’t apply the harmonic effector in the Physics tab, you apply it in the particle tab. Do this for the second mesh TYP_E as well, set it’s physics field to none.

Then in the particle TAB scroll to the bottom. Open up force field and where it says Type 1 choose the harmonic effector and use your settings from the Physics TAB there. Do this for both your mehses.

Thank you Atom! it seems it’s working much better now. I’m wondering what’s the purpose of the other Harmonics in the Physics tab…

A quick update: I’m trying now to tweak the timing accordingly to my needs, but as soon as I start to modify the Start / Stop emission for each meshes it gets messy. Same thing if I want to animate the Strength in the Harmonic fields… I’ll post a new file as soon as possible.

I’m getting confused with the timing settings. I’ve two examples, in the first one the main mesh emits particles from frames 1 to 30 and the harmonic mesh should start to emit from 100 to 110. But as you can see the particles start to move at frame 30. Therefore I thought that I had to change the end particle emission for the sphere nearest to the frame 100, so I ended the sphere emission at frame 90. It seems there’s no difference, the particles start to move at frame 30! The main difference is that the particles don’t hang to the torus and they move sooner and faster.

The two files here:

edit: also using a lower value for the Sphere’s emission (like for example from 1 to 10) doesn’t help, the particles always start to emit from frame 30!

It seems to be a bug. If I turn on the physics on the harmonic mesh, let’s say Newtonian, and then I clear the cache I can finally see the changes made in the Starting / Ending frames.

Besides that, I cannot completely stop the particles on the harmonic, they keep moving…

Try changing the strength of the harmonic effector applied to the torus from 5.0 to 20.0. A stronger strength will make them stick to the shape and drift less.

There may be a bug in there, but upping the strength does help out a lot. Also, I noticed that you have mis-matched lifetimes between the two particle systems. I believe that all the particle system participating should share the same lifetime as the originating system.

Thanks Atom, it’s getting closer. I can confirm that bug. Also if you for example add a new mesh to the scene and the particle system to it, again you’ve to reset the cache, also doable by changing the number of particles emission for all meshes. Bugs submitted.

Besides that, here’s the latest test of the day: I originally had two meshes, and it was working pretty well. Then added a cube, but the particle don’t reach the cube at least you don’t increase the harmonic strength, but then the particle move too fast.

edit: here’s the file

Yeah, it looks like a bug.

If you just want that feature, you can use 2.49. It works fine there.

Hmmm… I may be doing something wrong here, is not working in 2.49 too:


Feel free to pull down my Cherry 7up file here:

It is already setup.

Thank you a lot Atom for your help.
I’ll take a look your file, thanks for sharing it!

Bug submitted and fixed.
These guys are great!

Commit [31695] by: jhk 2010-09-01T17:03
Fix for [#23596] Particle Harmonics cache problem * Non-dynamic particles weren’t reset properly because they don’t use pointcache