  The Shape Calculus is a bio-inspired calculus for describing 3D shapes moving
in a space. A shape forms a 3D process when combined with a behaviour.
Behaviours are specified with a timed CCS-like process algebra using a notion
of channel that models naturally binding sites on the surface of shapes.
Processes can represent molecules or other mobile objects and can be part of
networks of processes that move simultaneously and interact in a given
geometrical space. The calculus embeds collision detection and response,
binding of compatible 3D processes and splitting of previously established
bonds. In this work the full formal timed operational semantics of the calculus
is provided, together with examples that illustrate the use of the calculus in
a well-known biological scenario. Moreover, a result of well-formedness about
the evolution of a given network of well-formed 3D processes is proved.
