Sample the isosurface of a scalar field at a given transition.

Input parameters:

1. Fl → Scalar field to sample.
2. Iv → Scalar value for isosurface intersection.
3. Bx → Sampling volume.
4. Ns → Number of sampling attempts.
5. Sz → Optional size of the soup elements.
6. Rd → Random engine to use during sampling.

Output parameters:

1. Ms → Hexagonal particles approximating the isosurface of the field.