How to avoid particles cut / intersect other particles

Hi,

is there any way to avoid particles cut / intersect other particles?
To make it more clear, I have a sphere and a particlesystem applied to it.
The distributed particles are small cubes. But I see that some of the cubes intersect with other cubes.
But I want to make sure that the cubes are put randomly everywhere on the surface of the sphere but must not intersect like if you glue real cubes onto a sphere. Is there any setting inside the particle system?

Thanks a lot for any help!

Hi,

thanks, I tried that but it does not really solve my problem. If I use ‘Self effect’ the particles start to look into the same direction. No longer randomized as I wish. And still there are particles overlapping. Is there any way to get this done?

The self effect technique only really works if your particles are generally cube-like or sphere-like in shape. The force effect is spherical originating at the particle location. If you are using a more complex particle or tube/rectangular mesh shapes you may still end up with some collision where particle mesh resides outside of the spherical influence.

Self Effect does have a checkbox to turn off affect rotation. Did you try that?

If you have an example BLEND file you can post I’ll take a look.

After re-reading your first post I tried to make a similar scene. A sphere with cubes randomly over the surface. I see what you mean about the Self Effect. However, I tried another approach. Leaving the Self Effect on Force and turning gravity off for the particle system the Self Effect acts like an explosion and pushes all the cubes out over time. I ran the particle simulation forward until all the cubes were well above the surface of the sphere. Then I made all the particle real and added them as Active Rigid Bodies. I made the Sphere a collision object and put a force field inside the sphere. The cubes now try to reach the center of the sphere, draw by the force, but fail because they collide with the Sphere surface and each other.

Not really the effect you are looking for, but fun to play around with a physics based solution.

You may want to search for tutorials on making Raspberries. I think I saw a tut that showed how to deploy self-colliding spheres along a stem.The technique might be close to what you are trying to accomplish.

Attachments


Hi Atom,

sorry for replying so lately. Thanks, interesting approach, I will give it a try.
Also the raspberries idea looks interesting to me!

Thanks!

Hi,

I still need help on this topic. I want to create air bubbles in water.
Air bubbles never intersect other bubbles, so this is a typical example where one needs to make particles not to intersect.
I need the air bubbles touching each other but never intersect - how can I do that?
Furthermore I want to create a still image where the particles/bubbles stick to the inside of the glass. So they must not intersect already if they are created. If I try using force fields to get this effect I have an animation where it takes some frames until the force takes effect, but then the bubbles have moved away from their original position which is not what I want.

Thanks a lot for any further idea!

Try using the standard particle system in Fluid mode. It seems to be designed for just such a use.

Attachments

268_fluid_particles.blend (727 KB)


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I also found an almost solution for your original post of cubes scattered across a sphere. There is still some slight intersection, but much better. Instead of using an actual Sphere object I used a cube and placed a sub-division surface modifier on the cube. This causes the cube to take on the shape of a sphere. But the faces are more evenly distributed and you do not get ‘bunching’ at the poles like you have with a UV Sphere. I put the particle system in Hair mode and used the cube as the hair particle.

Attachments


268_cube_across_sphere.blend (105 KB)

Hi Atom,

thanks for your effort, I tried with fluid particles, but they also intersect :-(.

Lol July 2013. 6 years later and I’m struggling with this myself, nobody knows how to do this :smiley:

Still can’t find a solution lol

I made the add-on that calculates collisions of particle objects and removes them.
Link on PSC add-on topic

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