SimpleSphere vs RotParticle

Hi Lukas,

SimpleSpheres only have translational degrees of freedom whereas RotSpheres also have rotational degrees of freedom. In ESyS-Particle the additional 3D orientation of each particle is represented by a Quaternion. The RotSphere() class implements additional subroutines for getting and setting the rotational properties of particles (e.g. orientation, angular velocity and angular acceleration), in addition to subroutines related to translational properties.

Whether you createParticles(..) using SimpleSphere or RotSphere depends upon your specified particleType provided as an argument to sim.initNeighbourSearch(..). If you selected "NRotSphere", then create particles using SimpleSphere. If you selected particleType="RotSphere", then use RotSphere objects to create particles.

Once particles are added to the simulation, they retain the properties appropriate for that particleType. Note that it is not possible to have NRotSpheres in a simulation with particleType="RotSphere" and vice versa. You can however suppress the rotational motion of specific particles using sim.setParticleNonRotational(..) for example.

I hope this helps.

Cheers,

Dion

Thanks Dion Weatherley, that solved my question.

After clicking the "Problem Solved"-Button I realized that I have an adjacent question.

If I create particles using RandomBoxPacker (RBP) I use the following steps (as I learned from the Tutorial):
packer = RandomBoxPacker(...)
packer.generate()
particleList = packer.getSimpleSphereCollection()
for particle in particleList:
 (some stuff like assigning tags)
 sim.createParticle(particle)

Because there is a function called getSimpleSphereCollection(), to me it looks like RBP generates a list of SimpleSphere objects. Can I use RBP in a simulation with RotSpheres even if it generates SimpleSpheres? The Tutorial does this so I assume the answer is yes? And following that, can I in general use SimpleSpheres in a RotSpheres-simulation? Dion's previous answer says no, but if RBP generates SimpleSpheres and the Tutorial uses RBP in RotSphere simulations, the answer would be yes. I hope you can see why I'm confused.

Best regards,
Lukas

Thanks Dion Weatherley, that solved my question.