Makes a simple atom for the given space. Coordinate is non-kinetic sphere;
node is for a leaf atom; type is a sphere with unit mass and unit size,
unique to the new atom; depth is 0.
public java.lang.String signature()
Returns a string of digits that uniquely identifies this atom. String is
formed by concatenating the ordinal of this atom to the signature
given by the parent of this atom. If atom has no parent, forms a string
from only the ordinal.
public final java.lang.String toString()
Returns a string formed by concatenating the signature of this atom
to a string that identifies it as a species master, species agent,
molecule, group, or (leaf) atom.
Returns the global index (within the Box) of this Atom. The global
index is unique to the IAtom in the Box. The IAtom's global may
change over the course of a simulation due to addition or removal of
other IAtoms in the Box. An BoxGlobalAtomIndexEvent is fired by
the Box's event manager when an Atom's global index changes.